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Shindell D, Faluvegi G, Nagamoto E, Parsons L, Zhang Y. Reductions in premature deaths from heat and particulate matter air pollution in South Asia, China, and the United States under decarbonization. Proc Natl Acad Sci U S A 2024; 121:e2312832120. [PMID: 38252836 PMCID: PMC10835032 DOI: 10.1073/pnas.2312832120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 11/22/2023] [Indexed: 01/24/2024] Open
Abstract
Following a sustainable development pathway designed to keep warming below 2 °C will benefit human health. We quantify premature deaths attributable to fine particulate matter (PM2.5) air pollution and heat exposures for China, South Asia, and the United States using projections from multiple climate models under high- and low-emission scenarios. Projected changes in premature deaths are typically dominated by population aging, primarily reflecting increased longevity leading to greater sensitivity to environmental risks. Changes in PM2.5 exposure typically have small impacts on premature deaths under a high-emission scenario but provide substantial benefits under a low-emission scenario. PM2.5-attributable deaths increase in South Asia throughout the century under both scenarios but shift to decreases by late century in China, and US values decrease throughout the century. In contrast, heat exposure increases under both scenarios and combines with population aging to drive projected increases in deaths in all countries. Despite population aging, combined PM2.5- and heat-related deaths decrease under the low-emission scenario by ~2.4 million per year by midcentury and ~2.9 million by century's end, with ~3% and ~21% of these reductions from heat, respectively. Intermodel variations in exposure projections generally lead to uncertainties of <40% except for US and China heat impacts. Health benefits of low emissions are larger from reduced heat exposure than improved air quality by the late 2090s in the United States. In contrast, in South and East Asia, the PM2.5-related benefits are largest throughout the century, and their valuation exceeds the cost of decarbonization, especially in China, over the next 30 y.
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Affiliation(s)
- Drew Shindell
- Earth and Climate Sciences Division, Nicholas School of the Environment, Duke University, Durham, NC27708
| | - Greg Faluvegi
- Center for Climate Systems Research, Columbia University, New York, NY10025
- NASA Goddard Institute for Space Studies, New York, NY10025
| | - Emily Nagamoto
- Earth and Climate Sciences Division, Nicholas School of the Environment, Duke University, Durham, NC27708
| | - Luke Parsons
- Earth and Climate Sciences Division, Nicholas School of the Environment, Duke University, Durham, NC27708
- Global Science, The Nature Conservancy, Salt Lake City, UT84102
| | - Yuqiang Zhang
- Environment Research Institute, Shandong University, Qingdao, Shandong250100, China
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Shindell D, Hunter R, Faluvegi G, Parsons L. Premature Deaths Due To Heat Exposure: The Potential Effects of Neighborhood-Level Versus City-Level Acclimatization Within US Cities. Geohealth 2024; 8:e2023GH000970. [PMID: 38169989 PMCID: PMC10759151 DOI: 10.1029/2023gh000970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 01/05/2024]
Abstract
For the population of a given US city, the risk of premature death associated with heat exposure increases as temperatures rise, but risks in hotter cities are generally lower than in cooler cities at equivalent temperatures due to factors such as acclimatization. Those living in especially hot neighborhoods within cities might therefore suffer much more than average if such adaptation is only at the city-wide level, whereas they might not experience greatly increased risk if adjustment is at the neighborhood level. To compare these possibilities, we use high spatial resolution temperature data to evaluated heat-related deaths assuming either adjustment at the city-wide or at the neighborhood scale in 10 large US cities. On average, we find that if inhabitants are adjusted to their local conditions, a neighborhood that was 10°C hotter than a cooler one would experience only about 1.0-1.5 excess heat deaths per year per 100,000 persons. By contrast, if inhabitants are acclimatized to city-wide temperatures, the hotter neighborhood would experience about 15 excess deaths per year per 100,000 persons. Using idealized analyses, we demonstrate that current city-wide epidemiological data do not differentiate between these differing adjustments. Given the very large effects of assumptions about neighborhood-level acclimatization found here, as well as the fact that current literature is conflicting on the spatial scale of acclimatization, more neighborhood-level epidemiological data are urgently needed to determine the health impacts of variations in heat exposure within urban areas, better constrain projected changes, and inform mitigation efforts.
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Affiliation(s)
- D. Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - R. Hunter
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - G. Faluvegi
- NASA Goddard Institute for Space Studies and Center for Climate Systems ResearchColumbia UniversityNew YorkNYUSA
| | - L. Parsons
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Global ScienceThe Nature ConservancyDurhamNCUSA
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3
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Ru M, Shindell D, Spadaro JV, Lamarque JF, Challapalli A, Wagner F, Kiesewetter G. New concentration-response functions for seven morbidity endpoints associated with short-term PM 2.5 exposure and their implications for health impact assessment. Environ Int 2023; 179:108122. [PMID: 37659174 DOI: 10.1016/j.envint.2023.108122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 07/26/2023] [Accepted: 07/28/2023] [Indexed: 09/04/2023]
Abstract
BACKGROUND Morbidity burdens from ambient air pollution are associated with market and non-market costs and are therefore important for policymaking. The estimation of morbidity burdens is based on concentration-response functions (CRFs). Most existing CRFs for short-term exposures to PM2.5 assume a fixed risk estimate as a log-linear function over an extrapolated exposure range, based on evidence primarily from Europe and North America. OBJECTIVES We revisit these CRFs by performing a systematic review for seven morbidity endpoints previously assessed by the World Health Organization, including data from all available regions. These endpoints include all cardiovascular hospital admission, all respiratory hospital admission, asthma hospital admission and emergency room visit, along with the outcomes that stem from morbidity, such as lost work days, respiratory restricted activity days, and child bronchitis symptom days. METHODS We estimate CRFs for each endpoint, using both a log-linear model and a nonlinear model that includes additional parameters to better fit evidence from high-exposure regions. We quantify uncertainties associated with these CRFs through randomization and Monte Carlo simulations. RESULTS The CRFs in this study show reduced model uncertainty compared with previous CRFs in all endpoints. The nonlinear CRFs produce more than doubled global estimates on average, depending on the endpoint. Overall, we assess that our CRFs can be used to provide policy analysis of air pollution impacts at the global scale. It is however important to note that improvement of CRFs requires observations over a wide range of conditions, and current available literature is still limited. DISCUSSION The higher estimates produced by the nonlinear CRFs indicates the possibility of a large underestimation in current assessments of the morbidity impacts attributable to air pollution. Further studies should be pursued to better constrain the CRFs studied here, and to better characterize the causal relationship between exposures to PM2.5 and morbidity outcomes.
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Affiliation(s)
- Muye Ru
- Nicholas School of the Environment, Duke University, Durham, NC, USA; Now at The Earth Institute, Columbia University, New York, NY, USA.
| | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, NC, USA; Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Joseph V Spadaro
- Spadaro Environmental Research Consultants, Philadelphia, PA, USA
| | | | | | - Fabian Wagner
- International Institute for Applied Systems Analysis, Laxenburg, Austria
| | - Gregor Kiesewetter
- International Institute for Applied Systems Analysis, Laxenburg, Austria
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Parsons LA, Lo F, Ward A, Shindell D, Raman SR. Higher Temperatures in Socially Vulnerable US Communities Increasingly Limit Safe Use of Electric Fans for Cooling. Geohealth 2023; 7:e2023GH000809. [PMID: 37577109 PMCID: PMC10413955 DOI: 10.1029/2023gh000809] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/09/2023] [Accepted: 07/09/2023] [Indexed: 08/15/2023]
Abstract
As the globe warms, people will increasingly need affordable, safe methods to stay cool and minimize the worst health impacts of heat exposure. One of the cheapest cooling methods is electric fans. Recent research has recommended ambient air temperature thresholds for safe fan use in adults. Here we use hourly weather reanalysis data (1950-2021) to examine the temporal and spatial evolution of ambient climate conditions in the continental United States (CONUS) considered safe for fan use, focusing on high social vulnerability index (SVI) regions. We find that although most hours in the day are safe for fan use, there are regions that experience hundreds to thousands of hours per year that are too hot for safe fan use. Over the last several decades, the number of hours considered unsafe for fan use has increased across most of the CONUS (on average by ∼70%), with hotspots across the US West and South, suggesting that many individuals will increasingly need alternative cooling strategies. People living in high-SVI locations are 1.5-2 times more likely to experience hotter climate conditions than the overall US population. High-SVI locations also experience higher rates of warming that are approaching and exceeding important safety thresholds that relate to climate adaptation. These results highlight the need to direct additional resources to these communities for heat adaptive strategies.
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Affiliation(s)
- L. A. Parsons
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Global ScienceThe Nature ConservancyDurhamNCUSA
| | - F. Lo
- Environmental Defense FundNew York CityNYUSA
| | - A. Ward
- Nicholas Institute for Energy, Environment, and SustainabilityDuke UniversityDurhamNCUSA
| | - D. Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - S. R. Raman
- Population Health SciencesDuke UniversityDurhamNCUSA
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Xie X, Myhre G, Shindell D, Faluvegi G, Takemura T, Voulgarakis A, Shi Z, Li X, Xie X, Liu H, Liu X, Liu Y. Anthropogenic sulfate aerosol pollution in South and East Asia induces increased summer precipitation over arid Central Asia. Commun Earth Environ 2022; 3:328. [PMID: 36588543 PMCID: PMC9792934 DOI: 10.1038/s43247-022-00660-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
Precipitation has increased across the arid Central Asia region over recent decades. However, the underlying mechanisms of this trend are poorly understood. Here, we analyze multi-model simulations from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP) to investigate potential drivers of the observed precipitation trend. We find that anthropogenic sulfate aerosols over remote polluted regions in South and East Asia lead to increased summer precipitation, especially convective and extreme precipitation, in arid Central Asia. Elevated concentrations of sulfate aerosols over remote polluted Asia cause an equatorward shift of the Asian Westerly Jet Stream through a fast response to cooling of the local atmosphere at mid-latitudes. This shift favours moisture supply from low-latitudes and moisture flux convergence over arid Central Asia, which is confirmed by a moisture budget analysis. High levels of absorbing black carbon lead to opposing changes in the Asian Westerly Jet Stream and reduced local precipitation, which can mask the impact of sulfate aerosols. This teleconnection between arid Central Asia precipitation and anthropogenic aerosols in remote Asian polluted regions highlights long-range impacts of anthropogenic aerosols on atmospheric circulations and the hydrological cycle.
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Affiliation(s)
- Xiaoning Xie
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
- CAS Center for Excellence in Quaternary Science and Global Change, Xi’an, China
| | - Gunnar Myhre
- Center for International Climate and Environmental Research, Oslo, Norway
| | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, USA
| | - Gregory Faluvegi
- Center for Climate System Research, Columbia University, New York, NY USA
- NASA Goddard Institute for Space Studies, New York, NY USA
| | | | - Apostolos Voulgarakis
- Department of Physics, Imperial College London, South Kensington Campus, London, UK
- School of Environmental Engineering, Technical University of Crete, Chania, Crete Greece
| | - Zhengguo Shi
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
| | - Xinzhou Li
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
| | - Xiaoxun Xie
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
| | - Heng Liu
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
- Xi’an Institute for Innovative Earth Environment Research, Xi’an, China
| | - Xiaodong Liu
- SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yangang Liu
- Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY USA
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Shindell D, Faluvegi G, Parsons L, Nagamoto E, Chang J. Premature Deaths in Africa Due To Particulate Matter Under High and Low Warming Scenarios. Geohealth 2022; 6:e2022GH000601. [PMID: 35573486 PMCID: PMC9077466 DOI: 10.1029/2022gh000601] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/06/2022] [Accepted: 04/19/2022] [Indexed: 06/15/2023]
Abstract
Sustainable development and climate change mitigation can provide enormous public health benefits via improved air quality, especially in polluted areas. We use the latest state-of-the-art composition-climate model simulations to contrast human exposure to fine particulate matter in Africa under a "baseline" scenario with high material consumption, population growth, and warming to that projected under a sustainability scenario with lower consumption, population growth, and warming. Evaluating the mortality impacts of these exposures, we find that under the low warming scenario annual premature deaths due to PM2.5 are reduced by roughly 515,000 by 2050 relative to the high warming scenario (100,000, 175,000, 55,000, 140,000, and 45,000 in Northern, West, Central, East, and Southern Africa, respectively). This reduction rises to ∼800,000 by the 2090s, though by that time much of the difference is attributable to the projected differences in population. By contrast, during the first half of the century benefits are driven predominantly by emissions changes. Depending on the region, we find large intermodel spreads of ∼25%-50% in projected future exposures owing to different physics across the ensemble of 6 global models. The spread of projected deaths attributable to exposure to fine particulate matter, including uncertainty in the exposure-response function, are reduced in every region to ∼20%-35% by the non-linear exposure-response function. Differences between the scenarios have an even narrower spread of ∼5%-25% and are highly statistically significant in all regions for all models. These results provide valuable information for policy-makers to consider when working toward climate change mitigation and sustainable development goals.
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Affiliation(s)
- D Shindell
- Nicholas School of the Environment Duke University Durham NC USA
| | - G Faluvegi
- Center for Climate Systems Research Columbia University New York NY USA
- NASA Goddard Institute for Space Studies New York NY USA
| | - L Parsons
- Nicholas School of the Environment Duke University Durham NC USA
| | - E Nagamoto
- Nicholas School of the Environment Duke University Durham NC USA
| | - J Chang
- Nicholas School of the Environment Duke University Durham NC USA
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7
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Lauvaux T, Giron C, Mazzolini M, d'Aspremont A, Duren R, Cusworth D, Shindell D, Ciais P. Global assessment of oil and gas methane ultra-emitters. Science 2022; 375:557-561. [PMID: 35113691 DOI: 10.1126/science.abj4351] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Methane emissions from oil and gas (O&G) production and transmission represent a considerable contribution to climate change. These emissions comprise sporadic releases of large amounts of methane during maintenance operations or equipment failures not accounted for in current inventory estimates. We collected and analyzed hundreds of very large releases from atmospheric methane images sampled by the TROPOspheric Monitoring Instrument (TROPOMI) between 2019 and 2020. Ultra-emitters are primarily detected over the largest O&G basins throughout the world. With a total contribution equivalent to 8 to 12% (~8 million metric tons of methane per year) of the global O&G production methane emissions, mitigation of ultra-emitters is largely achievable at low costs and would lead to robust net benefits in billions of US dollars for the six major O&G-producing countries when considering societal costs of methane.
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Affiliation(s)
- T Lauvaux
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, Univ. de Saclay, Saclay, France
| | - C Giron
- Kayrros, 33 rue Lafayette, 75009 Paris, France
| | - M Mazzolini
- Kayrros, 33 rue Lafayette, 75009 Paris, France
| | - A d'Aspremont
- Kayrros, 33 rue Lafayette, 75009 Paris, France.,CNRS & DI, Ecole Normale Supérieure, Paris, France
| | - R Duren
- Office of Research, Innovation and Impact, University of Arizona, Tucson, AZ, USA.,Carbon Mapper, 12 S. Raymond St., Suite B, Pasadena, CA 91105, USA
| | - D Cusworth
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - D Shindell
- Earth & Climate Sciences Division, Nicholas School of the Environment, Duke University, Durham, NC, USA.,Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel.,Climate and Clean Air Coalition, 1 Rue Miollis, Building VII, F-75015 Paris, France
| | - P Ciais
- Laboratoire des Sciences du Climat et de l'Environnement, IPSL, Univ. de Saclay, Saclay, France.,Climate and Atmosphere Research Centre, the Cyprus Institute (CyI), Nicosia, 2121, Cyprus
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Allen MR, Peters GP, Shine KP, Azar C, Balcombe P, Boucher O, Cain M, Ciais P, Collins W, Forster PM, Frame DJ, Friedlingstein P, Fyson C, Gasser T, Hare B, Jenkins S, Hamburg SP, Johansson DJA, Lynch J, Macey A, Morfeldt J, Nauels A, Ocko I, Oppenheimer M, Pacala SW, Pierrehumbert R, Rogelj J, Schaeffer M, Schleussner CF, Shindell D, Skeie RB, Smith SM, Tanaka K. Indicate separate contributions of long-lived and short-lived greenhouse gases in emission targets. NPJ Clim Atmos Sci 2022; 5:5. [PMID: 35295182 PMCID: PMC7612487 DOI: 10.1038/s41612-021-00226-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Affiliation(s)
- Myles R. Allen
- School of Geography and the Environment and Department of Physics, University of Oxford, Oxford, UK
| | - Glen P. Peters
- CICERO Centre for International Climate Research, Oslo, Norway
| | - Keith P. Shine
- Department of Meteorology, University of Reading, Reading, UK
| | | | | | | | | | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l’Environnement, Gif-sur-Yvette, France
| | | | | | - Dave J. Frame
- Victoria University of Wellington, Wellington, New Zealand
| | | | | | - Thomas Gasser
- International Institute for Applied Systems Analysis (IIASA), Vienna, Austria
| | | | | | | | | | | | - Adrian Macey
- Victoria University of Wellington, Wellington, New Zealand
| | | | | | - Ilissa Ocko
- Environmental Defence Fund, New York, NY, USA
| | | | | | | | | | | | | | | | | | | | - Katsumasa Tanaka
- Laboratoire des Sciences du Climat et de l’Environnement, Gif-sur-Yvette, France
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9
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Ru M, Brauer M, Lamarque J, Shindell D. Exploration of the Global Burden of Dementia Attributable to PM2.5: What Do We Know Based on Current Evidence? Geohealth 2021; 5:e2020GH000356. [PMID: 34084981 PMCID: PMC8143277 DOI: 10.1029/2020gh000356] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/15/2021] [Accepted: 03/11/2021] [Indexed: 05/17/2023]
Abstract
Exposure to ambient PM2.5 pollution has been linked to multiple adverse health effects. Additional effects have been identified in the literature and there is a need to understand its potential role in high prevalence diseases. In response to recent indications of PM2.5 as a risk factor for dementia, we examine the evidence by systematically reviewing the epidemiologic literature, in relation to exposure from ambient air pollution, household air pollution, secondhand smoke, and active smoking. We develop preliminary exposure-response functions, estimate the uncertainty, and discuss sensitivities and model selection. We estimate the likely impact to be 2.1 M (1.4 M, 2.5 M; 5%-95% confidence) global incident dementia cases and 0.6 M (0.4 M, 0.8 M) deaths attributable to ambient PM2.5 pollution in 2015. This implies a combined toll from morbidity and mortality of dementia of 7.3 M (5.0 M, 9.1 M) lost disability-adjusted life years. China, Japan, India, and the United States had the highest estimated total burden, and the per capita burden was highest in developed countries with large elderly populations. Compared to 2000, most countries in Europe, the Americas, and Southern Africa reduced the burden in 2015, while other regions had a net increase. Based on a recent systematic review of cost of illness studies for dementia, our estimates imply economic costs of US$ 26 billion worldwide in 2015. Based on this estimation, ambient PM2.5 pollution may be responsible for 15% of premature deaths and 7% of DALYs associated with dementia. Our estimates also indicate substantial uncertainty in this relationship, and future epidemiological studies at high exposure levels are especially needed.
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Affiliation(s)
- Muye Ru
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- The Earth InsititueColumbia UniversityNew York CityNYUSA
| | - Michael Brauer
- School of Population and Public HealthUniversity of British ColumbiaVancouverBCCanada
- Institute for Health Metrics and EvaluationUniversity of WashingtonSeattleWAUSA
| | | | - Drew Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Duke Global Health InitiativeDuke UniversityDurhamNCUSA
- Porter School of the Environment and Earth SciencesTel Aviv UniversityTel AvivIsrael
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10
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Hess JJ, Ranadive N, Boyer C, Aleksandrowicz L, Anenberg SC, Aunan K, Belesova K, Bell ML, Bickersteth S, Bowen K, Burden M, Campbell-Lendrum D, Carlton E, Cissé G, Cohen F, Dai H, Dangour AD, Dasgupta P, Frumkin H, Gong P, Gould RJ, Haines A, Hales S, Hamilton I, Hasegawa T, Hashizume M, Honda Y, Horton DE, Karambelas A, Kim H, Kim SE, Kinney PL, Kone I, Knowlton K, Lelieveld J, Limaye VS, Liu Q, Madaniyazi L, Martinez ME, Mauzerall DL, Milner J, Neville T, Nieuwenhuijsen M, Pachauri S, Perera F, Pineo H, Remais JV, Saari RK, Sampedro J, Scheelbeek P, Schwartz J, Shindell D, Shyamsundar P, Taylor TJ, Tonne C, Van Vuuren D, Wang C, Watts N, West JJ, Wilkinson P, Wood SA, Woodcock J, Woodward A, Xie Y, Zhang Y, Ebi KL. Guidelines for Modeling and Reporting Health Effects of Climate Change Mitigation Actions. Environ Health Perspect 2020; 128:115001. [PMID: 33170741 PMCID: PMC7654632 DOI: 10.1289/ehp6745] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 09/08/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Modeling suggests that climate change mitigation actions can have substantial human health benefits that accrue quickly and locally. Documenting the benefits can help drive more ambitious and health-protective climate change mitigation actions; however, documenting the adverse health effects can help to avoid them. Estimating the health effects of mitigation (HEM) actions can help policy makers prioritize investments based not only on mitigation potential but also on expected health benefits. To date, however, the wide range of incompatible approaches taken to developing and reporting HEM estimates has limited their comparability and usefulness to policymakers. OBJECTIVE The objective of this effort was to generate guidance for modeling studies on scoping, estimating, and reporting population health effects from climate change mitigation actions. METHODS An expert panel of HEM researchers was recruited to participate in developing guidance for conducting HEM studies. The primary literature and a synthesis of HEM studies were provided to the panel. Panel members then participated in a modified Delphi exercise to identify areas of consensus regarding HEM estimation. Finally, the panel met to review and discuss consensus findings, resolve remaining differences, and generate guidance regarding conducting HEM studies. RESULTS The panel generated a checklist of recommendations regarding stakeholder engagement: HEM modeling, including model structure, scope and scale, demographics, time horizons, counterfactuals, health response functions, and metrics; parameterization and reporting; approaches to uncertainty and sensitivity analysis; accounting for policy uptake; and discounting. DISCUSSION This checklist provides guidance for conducting and reporting HEM estimates to make them more comparable and useful for policymakers. Harmonization of HEM estimates has the potential to lead to advances in and improved synthesis of policy-relevant research that can inform evidence-based decision making and practice. https://doi.org/10.1289/EHP6745.
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Affiliation(s)
- Jeremy J. Hess
- Center for Health and the Global Environment, University of Washington, Seattle, Washington, USA
| | | | - Chris Boyer
- Center for Health and the Global Environment, University of Washington, Seattle, Washington, USA
| | | | - Susan C. Anenberg
- Milken Institute School of Public Health, George Washington University, Washington, District of Columbia, USA
| | - Kristin Aunan
- CICERO Center for International Climate Research, Oslo, Norway
| | - Kristine Belesova
- Department of Public Health, Environments, and Society, London School of Hygiene & Tropical Medicine, London, UK
- Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Michelle L. Bell
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut, USA
| | - Sam Bickersteth
- Rockefeller Foundation Economic Council on Planetary Health, Oxford, UK
| | | | - Marci Burden
- Center for Health and the Global Environment, University of Washington, Seattle, Washington, USA
| | - Diarmid Campbell-Lendrum
- Department of Environment Climate Change and Health, World Health Organization, Geneva, Switzerland
| | - Elizabeth Carlton
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado, Aurora, Colorado, USA
| | - Guéladio Cissé
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Francois Cohen
- Smith School for Enterprise and the Environment and Institute for New Economic Thinking at the Oxford Martin School, University of Oxford, Oxford, UK
| | - Hancheng Dai
- Laboratory of Energy & Environmental Economics and Policy (LEEEP), College of Environmental Sciences and Engineering, Peking University, Beijing, China
- College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Alan David Dangour
- Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Purnamita Dasgupta
- Environmental and Resource Economics Unit, Institute of Economic Growth, Delhi, India
| | | | - Peng Gong
- Department of Earth System Science, Tsinghua University, Beijing, China
| | - Robert J. Gould
- Center for Climate Change Communication, George Mason University, Fairfax, Virginia, USA
| | - Andy Haines
- Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Simon Hales
- Department of Public Health, University of Otago, Wellington, New Zealand
| | - Ian Hamilton
- UCL Energy Institute, University College London, London, UK
| | - Tomoko Hasegawa
- National Institute for Environmental Studies, Tsukuba, Japan
| | - Masahiro Hashizume
- Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
| | - Yasushi Honda
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Daniel E. Horton
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, Illinois, USA
| | | | - Ho Kim
- Department of Epidemiology and Biostatistics, School of Public Health, Seoul National University, Seoul, South Korea
| | - Satbyul Estella Kim
- Center for Climate Change Adaptation, National Institute for Environmental Studies, Tsukuba, Japan
| | - Patrick L. Kinney
- Department of Environmental Health, Boston University School of Public Health, Boston, USA
| | - Inza Kone
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Université Félix Houphouet-Boigny, Abidjan, Côte d’Ivoire
| | - Kim Knowlton
- Natural Resources Defense Council, New York, New York, USA
| | - Jos Lelieveld
- Max Planck Institute for Chemistry, Dept. of Atmospheric Chemistry, Mainz, Germany
| | | | - Qiyong Liu
- National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Lina Madaniyazi
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
- Department of Paediatric Diseases, Institute of Tropical Medicine, Nagasaki, Japan
| | - Micaela Elvira Martinez
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Denise L. Mauzerall
- Woodrow Wilson School of Public and International Affairs and the Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey, USA
| | - James Milner
- Department of Public Health, Environments, and Society, London School of Hygiene & Tropical Medicine, London, UK
| | | | - Mark Nieuwenhuijsen
- ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiologia y Salud Publica (CIBERESP), Barcelona, Spain
| | | | - Frederica Perera
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Helen Pineo
- Bartlett Faculty of the Built Environment, University College London, London, UK
| | - Justin V. Remais
- Division of Environmental Health Sciences, University of California, Berkeley, Berkeley, California, USA
| | - Rebecca K. Saari
- Civil and Environmental Engineering, University of Waterloo, Ontario, Canada
| | - Jon Sampedro
- Basque Centre for Climate Change (BC3), Leioa, Spain
| | - Pauline Scheelbeek
- Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK
- Department of Epidemiology & Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Joel Schwartz
- Department of Environmental Health, Harvard T.H. Chan School of Public Heath, Boston, Massachusetts, USA
| | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | | | - Timothy J. Taylor
- European Centre for Environment and Human Health, University of Exeter Medical School, Truro, Cornwall, UK
| | - Cathryn Tonne
- ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiologia y Salud Publica (CIBERESP), Barcelona, Spain
| | - Detlef Van Vuuren
- PBL Netherlands Environmental Assessment Agency, The Hague, Netherlands
| | - Can Wang
- School of Environment, Tsinghua University, Beijing, China
| | - Nicholas Watts
- Institute for Global Health, University College London, London, UK
| | - J. Jason West
- Environmental Sciences & Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Paul Wilkinson
- Department of Public Health, Environments, and Society, London School of Hygiene & Tropical Medicine, London, UK
| | - Stephen A. Wood
- School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut, USA
- The Nature Conservancy, New Haven, Connecticut, USA
| | - James Woodcock
- MRC Epidemiology Unit, University of Cambridge, Cambridge, UK
| | - Alistair Woodward
- Epidemiology and Biostatistics, University of Auckland, Auckland, New Zealand
| | - Yang Xie
- School of Economics and Management, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Beihang University, Beijing, China
| | - Ying Zhang
- School of Public Health, University of Sydney, New South Wales, Australia
| | - Kristie L. Ebi
- Center for Health and the Global Environment, University of Washington, Seattle, Washington, USA
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11
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Miyazaki K, Bowman K, Sekiya T, Jiang Z, Chen X, Eskes H, Ru M, Zhang Y, Shindell D. Air Quality Response in China Linked to the 2019 Novel Coronavirus (COVID-19) Lockdown. Geophys Res Lett 2020; 47:e2020GL089252. [PMID: 33173248 PMCID: PMC7646019 DOI: 10.1029/2020gl089252] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/21/2020] [Accepted: 09/08/2020] [Indexed: 05/20/2023]
Abstract
Efforts to stem the spread of COVID-19 in China hinged on severe restrictions to human movement starting 23 January 2020 in Wuhan and subsequently to other provinces. Here, we quantify the ancillary impacts on air pollution and human health using inverse emissions estimates based on multiple satellite observations. We find that Chinese NOx emissions were reduced by 36% from early January to mid-February, with more than 80% of reductions occurring after their respective lockdown in most provinces. The reduced precursor emissions increased surface ozone by up to 16 ppb over northern China but decreased PM2.5 by up to 23 μg m-3 nationwide. Changes in human exposure are associated with about 2,100 more ozone-related and at least 60,000 fewer PM2.5-related morbidity incidences, primarily from asthma cases, thereby augmenting efforts to reduce hospital admissions and alleviate negative impacts from potential delayed treatments.
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Affiliation(s)
- K. Miyazaki
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - K. Bowman
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - T. Sekiya
- Japan Agency for Marine‐Earth Science and TechnologyYokohamaJapan
| | - Z. Jiang
- School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefeiChina
| | - X. Chen
- School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefeiChina
| | - H. Eskes
- Royal Netherlands Meteorological Institute (KNMI)De Biltthe Netherlands
| | - M. Ru
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - Y. Zhang
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - D. Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Porter School of the Environment and Earth SciencesTel Aviv UniversityTel AvivIsrael
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12
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Agrawala S, Amann M, Binimelis de Raga G, Borgford-Parnell N, Brauer M, Clark H, Emberson L, Haines A, Kejun J, Künzli N, Kuylenstierna J, Lacy R, Liu J, Mulugetta Y, Pachauri S, Ramanathan V, Ravishankara AR, Shindell D, Wongwangwatana S. Call for comments: climate and clean air responses to covid-19. Int J Public Health 2020; 65:525-528. [PMID: 32458072 PMCID: PMC7248189 DOI: 10.1007/s00038-020-01394-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/03/2020] [Accepted: 05/14/2020] [Indexed: 11/28/2022] Open
Affiliation(s)
- Shardul Agrawala
- Organization for Economic Co-operation and Development, Paris, France
| | - Markus Amann
- International Institute for Applied Systems Analysis, Laxenburg, Austria
| | | | | | - Michael Brauer
- School of Population and Public Health, University of British Columbia, Vancouver, Canada
| | - Harry Clark
- New Zealand Agricultural Greenhouse Gas Research Centre, Palmerston North, New Zealand
| | | | - Andy Haines
- London School of Hygiene and Tropical Medicine, London, UK
| | - Jiang Kejun
- Energy Research Institute, National Development and Reform Commission, Beijing, China
| | - Nino Künzli
- Swiss Tropical and Public Health Institute, Bern, Switzerland
| | | | - Rodolfo Lacy
- Organization for Economic Co-operation and Development, Paris, France
| | - Jian Liu
- UN Environment Programme, Nairobi, Kenya
| | - Yacob Mulugetta
- Department of Science, Technology, Engineering and Public Policy, University College London, London, UK
| | - Shonali Pachauri
- International Institute for Applied Systems Analysis, Laxenburg, Austria
| | - V. Ramanathan
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, USA
| | - A. R. Ravishankara
- Department of Atmospheric Science, Colorado State University, Fort Collins, USA
| | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, USA
| | | | - Scientific Advisory Panel of the Climate and Clean Air Coalition and Invited Experts
- Organization for Economic Co-operation and Development, Paris, France
- International Institute for Applied Systems Analysis, Laxenburg, Austria
- Universidad Nacional Autónoma de México, Mexico City, Mexico
- Climate and Clean Air Coalition, Paris, France
- School of Population and Public Health, University of British Columbia, Vancouver, Canada
- New Zealand Agricultural Greenhouse Gas Research Centre, Palmerston North, New Zealand
- Stockholm Environment Institute, York, UK
- London School of Hygiene and Tropical Medicine, London, UK
- Energy Research Institute, National Development and Reform Commission, Beijing, China
- Swiss Tropical and Public Health Institute, Bern, Switzerland
- UN Environment Programme, Nairobi, Kenya
- Department of Science, Technology, Engineering and Public Policy, University College London, London, UK
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, USA
- Department of Atmospheric Science, Colorado State University, Fort Collins, USA
- Nicholas School of the Environment, Duke University, Durham, USA
- Faculty of Public Health, Thammasat University, Bangkok, Thailand
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13
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Shindell D, Zhang Y, Scott M, Ru M, Stark K, Ebi KL. The Effects of Heat Exposure on Human Mortality Throughout the United States. Geohealth 2020; 4:e2019GH000234. [PMID: 32258942 PMCID: PMC7125937 DOI: 10.1029/2019gh000234] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/17/2020] [Accepted: 03/12/2020] [Indexed: 05/10/2023]
Abstract
Exposure to high ambient temperatures is an important cause of avoidable, premature death that may become more prevalent under climate change. Though extensive epidemiological data are available in the United States, they are largely limited to select large cities, and hence, most projections estimate the potential impact of future warming on a subset of the U.S. population. Here we utilize evaluations of the relative risk of premature death associated with temperature in 10 U.S. cities spanning a wide range of climate conditions to develop a generalized risk function. We first evaluate the performance of this generalized function, which introduces substantial biases at the individual city level but performs well at the large scale. We then apply this function to estimate the impacts of projected climate change on heat-related nationwide U.S. deaths under a range of scenarios. During the current decade, there are 12,000 (95% confidence interval 7,400-16,500) premature deaths annually in the contiguous United States, much larger than most estimates based on totals for select individual cities. These values increase by 97,000 (60,000-134,000) under the high-warming Representative Concentration Pathway (RCP) 8.5 scenario and by 36,000 (22,000-50,000) under the moderate RCP4.5 scenario by 2100, whereas they remain statistically unchanged under the aggressive mitigation scenario RCP2.6. These results include estimates of adaptation that reduce impacts by ~40-45% as well as population increases that roughly offset adaptation. The results suggest that the degree of climate change mitigation will have important health impacts on Americans.
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Affiliation(s)
- Drew Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Duke Global Health InitiativeDuke UniversityDurhamNCUSA
- Porter School of the Environment and Earth SciencesTel Aviv UniversityTel AvivIsrael
| | - Yuqiang Zhang
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - Melissa Scott
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
- Now at the Samuel DuBois Cook Center on Social EquityDuke UniversityDurhamNCUSA
| | - Muye Ru
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - Krista Stark
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - Kristie L. Ebi
- Center for Health and the Global EnvironmentUniversity of WashingtonSeattleWAUSA
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14
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Richardson TB, Forster PM, Smith CJ, Maycock AC, Wood T, Andrews T, Boucher O, Faluvegi G, Fläschner D, Hodnebrog Ø, Kasoar M, Kirkevåg A, Lamarque J, Mülmenstädt J, Myhre G, Olivié D, Portmann RW, Samset BH, Shawki D, Shindell D, Stier P, Takemura T, Voulgarakis A, Watson‐Parris D. Efficacy of Climate Forcings in PDRMIP Models. J Geophys Res Atmos 2019; 124:12824-12844. [PMID: 32025453 PMCID: PMC6988499 DOI: 10.1029/2019jd030581] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 05/04/2023]
Abstract
Quantifying the efficacy of different climate forcings is important for understanding the real-world climate sensitivity. This study presents a systematic multimodel analysis of different climate driver efficacies using simulations from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP). Efficacies calculated from instantaneous radiative forcing deviate considerably from unity across forcing agents and models. Effective radiative forcing (ERF) is a better predictor of global mean near-surface air temperature (GSAT) change. Efficacies are closest to one when ERF is computed using fixed sea surface temperature experiments and adjusted for land surface temperature changes using radiative kernels. Multimodel mean efficacies based on ERF are close to one for global perturbations of methane, sulfate, black carbon, and insolation, but there is notable intermodel spread. We do not find robust evidence that the geographic location of sulfate aerosol affects its efficacy. GSAT is found to respond more slowly to aerosol forcing than CO2 in the early stages of simulations. Despite these differences, we find that there is no evidence for an efficacy effect on historical GSAT trend estimates based on simulations with an impulse response model, nor on the resulting estimates of climate sensitivity derived from the historical period. However, the considerable intermodel spread in the computed efficacies means that we cannot rule out an efficacy-induced bias of ±0.4 K in equilibrium climate sensitivity to CO2 doubling when estimated using the historical GSAT trend.
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Affiliation(s)
- T. B. Richardson
- Priestley International Centre for ClimateUniversity of LeedsLeedsUK
| | - P. M. Forster
- Priestley International Centre for ClimateUniversity of LeedsLeedsUK
| | - C. J. Smith
- Priestley International Centre for ClimateUniversity of LeedsLeedsUK
| | - A. C. Maycock
- Priestley International Centre for ClimateUniversity of LeedsLeedsUK
| | - T. Wood
- Priestley International Centre for ClimateUniversity of LeedsLeedsUK
| | | | - O. Boucher
- Institut Pierre‐Simon LaplaceCNRS/Sorbonne UniversitéParisFrance
| | - G. Faluvegi
- NASA Goddard Institute for Space Studies and Center for Climate Systems ResearchColumbia UniversityNew YorkNYUSA
| | - D. Fläschner
- Atmosphere in the Earth SystemMax‐Planck‐Institut für MeteorologieHamburgGermany
| | - Ø. Hodnebrog
- CICERO Center for International Climate and Environmental ResearchOsloNorway
| | - M. Kasoar
- Department of PhysicsImperial College LondonLondonUK
| | - A. Kirkevåg
- Research and Development DepartmentNorwegian Meteorological InstituteOsloNorway
| | | | - J. Mülmenstädt
- Clouds and Global ClimateUniversität LeipzigLeipzigGermany
| | - G. Myhre
- CICERO Center for International Climate and Environmental ResearchOsloNorway
| | - D. Olivié
- Research and Development DepartmentNorwegian Meteorological InstituteOsloNorway
| | - R. W. Portmann
- Earth System Research LaboratoryNational Oceanic and Atmospheric AdministrationBoulderCOUSA
| | - B. H. Samset
- CICERO Center for International Climate and Environmental ResearchOsloNorway
| | - D. Shawki
- Department of PhysicsImperial College LondonLondonUK
| | - D. Shindell
- Earth & Ocean SciencesDuke UniversityDurhamNCUSA
| | - P. Stier
- Atmospheric, Oceanic and Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
| | - T. Takemura
- Center for Oceanic and Atmospheric ResearchKyushu UniversityFukuokaJapan
| | | | - D. Watson‐Parris
- Atmospheric, Oceanic and Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
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15
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Abstract
The combustion of fossil fuels produces emissions of the long-lived greenhouse gas carbon dioxide and of short-lived pollutants, including sulfur dioxide, that contribute to the formation of atmospheric aerosols1. Atmospheric aerosols can cool the climate, masking some of the warming effect that results from the emission of greenhouse gases1. However, aerosol particulates are highly toxic when inhaled, leading to millions of premature deaths per year2,3. The phasing out of unabated fossil-fuel combustion will therefore provide health benefits, but will also reduce the extent to which the warming induced by greenhouse gases is masked by aerosols. Because aerosol levels respond much more rapidly to changes in emissions relative to carbon dioxide, large near-term increases in the magnitude and rate of climate warming are predicted in many idealized studies that typically assume an instantaneous removal of all anthropogenic or fossil-fuel-related emissions1,4-9. Here we show that more realistic modelling scenarios do not produce a substantial near-term increase in either the magnitude or the rate of warming, and in fact can lead to a decrease in warming rates within two decades of the start of the fossil-fuel phase-out. Accounting for the time required to transform power generation, industry and transportation leads to gradually increasing and largely offsetting climate impacts of carbon dioxide and sulfur dioxide, with the rate of warming further slowed by reductions in fossil-methane emissions. Our results indicate that even the most aggressive plausible transition to a clean-energy society provides benefits for climate change mitigation and air quality at essentially all decadal to centennial timescales.
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Affiliation(s)
- Drew Shindell
- Nicholas School of the Environment and Duke Global Health Initiative, Duke University, Durham, NC, USA. .,Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel.
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16
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Shindell D, Faluvegi G, Kasibhatla P, Van Dingenen R. Spatial Patterns of Crop Yield Change by Emitted Pollutant. Earths Future 2019; 7:101-112. [PMID: 31008141 PMCID: PMC6472474 DOI: 10.1029/2018ef001030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 12/07/2018] [Accepted: 01/15/2019] [Indexed: 06/09/2023]
Abstract
Field measurements and modeling have examined how temperature, precipitation, and exposure to carbon dioxide (CO2) and ozone affect major staple crops around the world. Most prior studies, however, have incorporated only a subset of these influences. Here we examine how emissions of each individual pollutant driving changes in these four factors affect present-day yields of wheat, maize (corn), and rice worldwide. Our statistical modeling indicates that for the global mean, climate and composition changes have decreased wheat and maize yields substantially whereas rice yields have increased. Well-mixed greenhouse gasses drive most of the impacts, though aerosol-induced cooling can be important, particularly for more polluted area including India and China. Maize yield losses are most strongly attributable to methane emissions (via both temperature and ozone). In tropical areas, wheat yield losses are primarily driven by CO2 (via temperature), whereas in temperate zones other well-mixed greenhouse gases dominate. Rice yields increase in tropical countries due to a larger impact from CO2 fertilization plus aerosol-induced cooling than losses due to CO2-induced warming and impacts of non-CO2 gasses, whereas there are net losses in temperate zones driven largely by methane and other non-CO2 gasses. Though further work is needed, particularly on the effects of aerosol changes and on nutritional impacts, these results suggest that crop yields over coming decades will be strongly influenced by changes in non-CO2 greenhouse gasses, ozone precursors, and aerosols and that these should be taking into account in plant-level models and when examining linkages between climate change mitigation and sustainable development.
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Affiliation(s)
- Drew Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - Greg Faluvegi
- NASA Goddard Institute for Space Studies and Center for Climate Systems ResearchColumbia UniversityNew YorkNYUSA
| | | | - Rita Van Dingenen
- Directorate for Energy, Transport and Climate, European CommissionJoint Research CentreIspraItaly
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17
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Aas W, Mortier A, Bowersox V, Cherian R, Faluvegi G, Fagerli H, Hand J, Klimont Z, Galy-Lacaux C, Lehmann CMB, Myhre CL, Myhre G, Olivié D, Sato K, Quaas J, Rao PSP, Schulz M, Shindell D, Skeie RB, Stein A, Takemura T, Tsyro S, Vet R, Xu X. Global and regional trends of atmospheric sulfur. Sci Rep 2019; 9:953. [PMID: 30700755 PMCID: PMC6353995 DOI: 10.1038/s41598-018-37304-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/05/2018] [Indexed: 11/09/2022] Open
Abstract
The profound changes in global SO2 emissions over the last decades have affected atmospheric composition on a regional and global scale with large impact on air quality, atmospheric deposition and the radiative forcing of sulfate aerosols. Reproduction of historical atmospheric pollution levels based on global aerosol models and emission changes is crucial to prove that such models are able to predict future scenarios. Here, we analyze consistency of trends in observations of sulfur components in air and precipitation from major regional networks and estimates from six different global aerosol models from 1990 until 2015. There are large interregional differences in the sulfur trends consistently captured by the models and observations, especially for North America and Europe. Europe had the largest reductions in sulfur emissions in the first part of the period while the highest reduction came later in North America and East Asia. The uncertainties in both the emissions and the representativity of the observations are larger in Asia. However, emissions from East Asia clearly increased from 2000 to 2005 followed by a decrease, while in India a steady increase over the whole period has been observed and modelled. The agreement between a bottom-up approach, which uses emissions and process-based chemical transport models, with independent observations gives an improved confidence in the understanding of the atmospheric sulfur budget.
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Affiliation(s)
- Wenche Aas
- NILU -Norwegian Institute for Air Research, Kjeller, Norway.
| | | | | | - Ribu Cherian
- Institute for Meteorology, Universität Leipzig, Leipzig, Germany
| | - Greg Faluvegi
- NASA Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, USA
| | | | - Jenny Hand
- Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO, USA
| | - Zbigniew Klimont
- International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria
| | - Corinne Galy-Lacaux
- Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France
| | | | | | - Gunnar Myhre
- Center for International Climate and Environmental Research - Oslo (CICERO), Oslo, Norway
| | - Dirk Olivié
- Norwegian Meteorological Institute, Oslo, Norway
| | - Keiichi Sato
- Asia Center for Air Pollution Research (ACAP), Niigata, Japan
| | - Johannes Quaas
- Institute for Meteorology, Universität Leipzig, Leipzig, Germany
| | - P S P Rao
- Indian Institute of Tropical Meteorology, Pune, India
| | | | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Ragnhild B Skeie
- Center for International Climate and Environmental Research - Oslo (CICERO), Oslo, Norway
| | | | - Toshihiko Takemura
- Research Institute for Applied Mechanics, Kyushu University, Fukuoka, Japan
| | | | - Robert Vet
- Environment and Climate Change Canada, Toronto, Canada
| | - Xiaobin Xu
- Chinese Academy of Meteorological Sciences, Key Laboratory for Atmospheric Chemistry, China Meteorological Administration, Beijing, China
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18
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Smith CJ, Kramer RJ, Myhre G, Forster PM, Soden BJ, Andrews T, Boucher O, Faluvegi G, Fläschner D, Hodnebrog Ø, Kasoar M, Kharin V, Kirkevåg A, Lamarque J, Mülmenstädt J, Olivié D, Richardson T, Samset BH, Shindell D, Stier P, Takemura T, Voulgarakis A, Watson‐Parris D. Understanding Rapid Adjustments to Diverse Forcing Agents. Geophys Res Lett 2018; 45:12023-12031. [PMID: 30686845 PMCID: PMC6334512 DOI: 10.1029/2018gl079826] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/10/2018] [Accepted: 10/15/2018] [Indexed: 05/04/2023]
Abstract
Rapid adjustments are responses to forcing agents that cause a perturbation to the top of atmosphere energy budget but are uncoupled to changes in surface warming. Different mechanisms are responsible for these adjustments for a variety of climate drivers. These remain to be quantified in detail. It is shown that rapid adjustments reduce the effective radiative forcing (ERF) of black carbon by half of the instantaneous forcing, but for CO2 forcing, rapid adjustments increase ERF. Competing tropospheric adjustments for CO2 forcing are individually significant but sum to zero, such that the ERF equals the stratospherically adjusted radiative forcing, but this is not true for other forcing agents. Additional experiments of increase in the solar constant and increase in CH4 are used to show that a key factor of the rapid adjustment for an individual climate driver is changes in temperature in the upper troposphere and lower stratosphere.
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Affiliation(s)
- C. J. Smith
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - R. J. Kramer
- Rosenstiel School of Marine and Atmospheric ScienceUniversity of MiamiMiamiFLUSA
| | - G. Myhre
- CICERO Center for International Climate and Environmental Research in OsloOsloNorway
| | - P. M. Forster
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - B. J. Soden
- Rosenstiel School of Marine and Atmospheric ScienceUniversity of MiamiMiamiFLUSA
| | | | - O. Boucher
- Institut Pierre‐Simon Laplace, CNRS/Sorbonne UniversitéParisFrance
| | - G. Faluvegi
- NASA Goddard Institute for Space StudiesNew YorkNYUSA
- Center for Climate Systems ResearchColumbia UniversityNew YorkNYUSA
| | - D. Fläschner
- Max‐Planck‐Institut für MeteorologieHamburgGermany
| | - Ø. Hodnebrog
- CICERO Center for International Climate and Environmental Research in OsloOsloNorway
| | - M. Kasoar
- Department of PhysicsImperial College LondonLondonUK
- Grantham Institute – Climate Change and the EnvironmentImperial College LondonLondonUK
| | - V. Kharin
- Canadian Centre for Climate Modelling and AnalysisVictoriaBritish ColumbiaCanada
| | - A. Kirkevåg
- Norwegian Meteorological InstituteOsloNorway
| | | | - J. Mülmenstädt
- Institute of MeteorologyUniversität LeipzigLeipzigGermany
| | - D. Olivié
- Norwegian Meteorological InstituteOsloNorway
| | - T. Richardson
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - B. H. Samset
- CICERO Center for International Climate and Environmental Research in OsloOsloNorway
| | - D. Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - P. Stier
- Atmospheric, Oceanic and Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
| | | | | | - D. Watson‐Parris
- Atmospheric, Oceanic and Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
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19
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Myhre G, Kramer RJ, Smith CJ, Hodnebrog Ø, Forster P, Soden BJ, Samset BH, Stjern CW, Andrews T, Boucher O, Faluvegi G, Fläschner D, Kasoar M, Kirkevåg A, Lamarque J, Olivié D, Richardson T, Shindell D, Stier P, Takemura T, Voulgarakis A, Watson‐Parris D. Quantifying the Importance of Rapid Adjustments for Global Precipitation Changes. Geophys Res Lett 2018; 45:11399-11405. [PMID: 30774164 PMCID: PMC6360531 DOI: 10.1029/2018gl079474] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 10/09/2018] [Accepted: 10/12/2018] [Indexed: 05/04/2023]
Abstract
Different climate drivers influence precipitation in different ways. Here we use radiative kernels to understand the influence of rapid adjustment processes on precipitation in climate models. Rapid adjustments are generally triggered by the initial heating or cooling of the atmosphere from an external climate driver. For precipitation changes, rapid adjustments due to changes in temperature, water vapor, and clouds are most important. In this study we have investigated five climate drivers (CO2, CH4, solar irradiance, black carbon, and sulfate aerosols). The fast precipitation responses to a doubling of CO2 and a 10-fold increase in black carbon are found to be similar, despite very different instantaneous changes in the radiative cooling, individual rapid adjustments, and sensible heating. The model diversity in rapid adjustments is smaller for the experiment involving an increase in the solar irradiance compared to the other climate driver perturbations, and this is also seen in the precipitation changes.
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Affiliation(s)
- G. Myhre
- CICERO Center for International Climate ResearchOsloNorway
| | - R. J. Kramer
- Rosenstiel School of Marine and Atmospheric ScienceUniversity of MiamiMiamiFLUSA
| | - C. J. Smith
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - Ø. Hodnebrog
- CICERO Center for International Climate ResearchOsloNorway
| | - P. Forster
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - B. J. Soden
- Rosenstiel School of Marine and Atmospheric ScienceUniversity of MiamiMiamiFLUSA
| | - B. H. Samset
- CICERO Center for International Climate ResearchOsloNorway
| | - C. W. Stjern
- CICERO Center for International Climate ResearchOsloNorway
| | | | - O. Boucher
- Institut Pierre‐Simon LaplaceCNRS/Sorbonne UniversitéParisFrance
| | - G. Faluvegi
- NASA Goddard Institute for Space StudiesNew YorkNYUSA
- Center for Climate Systems ResearchColumbia UniversityNew YorkNYUSA
| | - D. Fläschner
- Max‐Planck‐Institut für MeteorologieHamburgGermany
| | - M. Kasoar
- Department of PhysicsImperial College LondonLondonUK
- Grantham Institute‐Climate Change and the EnvironmentImperial College LondonLondonUK
| | - A. Kirkevåg
- Norwegian Meteorological InstituteOsloNorway
| | | | - D. Olivié
- Norwegian Meteorological InstituteOsloNorway
| | - T. Richardson
- School of Earth and EnvironmentUniversity of LeedsLeedsUK
| | - D. Shindell
- Nicholas School of the EnvironmentDuke UniversityDurhamNCUSA
| | - P. Stier
- Atmospheric, Oceanic & Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
| | - T. Takemura
- Research Institute for Applied MechanicsKyushu UniversityFukuokaJapan
| | | | - D. Watson‐Parris
- Atmospheric, Oceanic & Planetary Physics, Department of PhysicsUniversity of OxfordOxfordUK
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20
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Liu L, Shawki D, Voulgarakis A, Kasoar M, Samset BH, Myhre G, Forster PM, Hodnebrog Ø, Sillmann J, Aalbergsjø SG, Boucher O, Faluvegi G, Iversen T, Kirkevåg A, Lamarque JF, Olivié D, Richardson T, Shindell D, Takemura T. A PDRMIP multi-model study on the impacts of regional aerosol forcings on global and regional precipitation. J Clim 2018; 31:4429-4447. [PMID: 32704205 PMCID: PMC7376680 DOI: 10.1175/jcli-d-17-0439.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Atmospheric aerosols such as sulfate and black carbon (BC) generate inhomogeneous radiative forcing and can affect precipitation in distinct ways compared to greenhouse gases (GHGs). Their regional effects on the atmospheric energy budget and circulation can be important for understanding and predicting global and regional precipitation changes, which act on top of the background GHG-induced hydrological changes. Under the framework of the Precipitation Driver Response Model Inter-comparison Project (PDRMIP), multiple models were used for the first time to simulate the influence of regional (Asian and European) sulfate and BC forcing on global and regional precipitation. The results show that, as in the case of global aerosol forcing, the global fast precipitation response to regional aerosol forcing scales with global atmospheric absorption, and the slow precipitation response scales with global surface temperature response. Asian sulphate aerosols appear to be a stronger driver of global temperature and precipitation change compared to European aerosols, but when the responses are normalised by unit radiative forcing or by aerosol burden change, the picture reverses, with European aerosols being more efficient in driving global change. The global apparent hydrological sensitivities of these regional forcing experiments are again consistent with those for corresponding global aerosol forcings found in the literature. However, the regional responses and regional apparent hydrological sensitivities do not align with the corresponding global values. Through a holistic approach involving analysis of the energy budget combined with exploring changes in atmospheric dynamics, we provide a framework for explaining the global and regional precipitation responses to regional aerosol forcing.
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Affiliation(s)
- L Liu
- Department of Physics, Imperial College London, London, UK and Northwest Institute of Nuclear Technology, Xi'an, China
| | - D Shawki
- Department of Physics, Imperial College London, London, UK
| | - A Voulgarakis
- Department of Physics, Imperial College London, London, UK
| | - M Kasoar
- Department of Physics, Imperial College London, London, UK
| | - B H Samset
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - G Myhre
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | - Ø Hodnebrog
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - J Sillmann
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - S G Aalbergsjø
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - O Boucher
- Institut Pierre-Simon Laplace, Univ. P. et M. Curie / CNRS, Paris, France
| | - G Faluvegi
- Columbia University & NASA Goddard Institute for Space Studies, New York, USA
| | - T Iversen
- Norwegian Meteorological Institute, Oslo, Norway
| | - A Kirkevåg
- Norwegian Meteorological Institute, Oslo, Norway
| | | | - D Olivié
- Norwegian Meteorological Institute, Oslo
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21
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Myhre G, Samset BH, Hodnebrog Ø, Andrews T, Boucher O, Faluvegi G, Fläschner D, Forster PM, Kasoar M, Kharin V, Kirkevåg A, Lamarque JF, Olivié D, Richardson TB, Shawki D, Shindell D, Shine KP, Stjern CW, Takemura T, Voulgarakis A. Sensible heat has significantly affected the global hydrological cycle over the historical period. Nat Commun 2018; 9:1922. [PMID: 29765048 PMCID: PMC5954152 DOI: 10.1038/s41467-018-04307-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 04/17/2018] [Indexed: 11/15/2022] Open
Abstract
Globally, latent heating associated with a change in precipitation is balanced by changes to atmospheric radiative cooling and sensible heat fluxes. Both components can be altered by climate forcing mechanisms and through climate feedbacks, but the impacts of climate forcing and feedbacks on sensible heat fluxes have received much less attention. Here we show, using a range of climate modelling results, that changes in sensible heat are the dominant contributor to the present global-mean precipitation change since preindustrial time, because the radiative impact of forcings and feedbacks approximately compensate. The model results show a dissimilar influence on sensible heat and precipitation from various drivers of climate change. Due to its strong atmospheric absorption, black carbon is found to influence the sensible heat very differently compared to other aerosols and greenhouse gases. Our results indicate that this is likely caused by differences in the impact on the lower tropospheric stability.
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Affiliation(s)
- G Myhre
- CICERO Center for International Climate Research - Oslo, 0318, Oslo, Norway.
| | - B H Samset
- CICERO Center for International Climate Research - Oslo, 0318, Oslo, Norway
| | - Ø Hodnebrog
- CICERO Center for International Climate Research - Oslo, 0318, Oslo, Norway
| | - T Andrews
- Met Office Hadley Centre, Devon, EX1 3PB, United Kingdom
| | - O Boucher
- Institut Pierre-Simon Laplace, CNRS/Sorbonne Université, 75252, Paris, Cedex 05, France
| | - G Faluvegi
- NASA Goddard Institute for Space Studies, New York, NY, 10025, USA
- Center for Climate Systems Research, Columbia University, New York, NY, 10027, USA
| | - D Fläschner
- Max-Planck-Institut für Meteorologie, 20146, Hamburg, Germany
| | - P M Forster
- University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - M Kasoar
- Department of Physics, Imperial College London, London, SW7 2AZ, United Kingdom
| | - V Kharin
- Canadian Centre for Climate Modelling and Analysis, V8P 5C2, Victoria, BC,, Canada
| | - A Kirkevåg
- Norwegian Meteorological Institute, 0313, Oslo, Norway
| | | | - D Olivié
- Norwegian Meteorological Institute, 0313, Oslo, Norway
| | | | - D Shawki
- Department of Physics, Imperial College London, London, SW7 2AZ, United Kingdom
| | | | - K P Shine
- University of Reading, Reading, RG6 6BB, United Kingdom
| | - C W Stjern
- CICERO Center for International Climate Research - Oslo, 0318, Oslo, Norway
| | - T Takemura
- Kyushu University, 816-8580, Kasuga, Japan
| | - A Voulgarakis
- Department of Physics, Imperial College London, London, SW7 2AZ, United Kingdom
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22
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Fuglestvedt J, Rogelj J, Millar RJ, Allen M, Boucher O, Cain M, Forster PM, Kriegler E, Shindell D. Implications of possible interpretations of 'greenhouse gas balance' in the Paris Agreement. Philos Trans A Math Phys Eng Sci 2018; 376:20160445. [PMID: 29610378 PMCID: PMC5897819 DOI: 10.1098/rsta.2016.0445] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/21/2017] [Indexed: 05/20/2023]
Abstract
The main goal of the Paris Agreement as stated in Article 2 is 'holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C'. Article 4 points to this long-term goal and the need to achieve 'balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases'. This statement on 'greenhouse gas balance' is subject to interpretation, and clarifications are needed to make it operational for national and international climate policies. We study possible interpretations from a scientific perspective and analyse their climatic implications. We clarify how the implications for individual gases depend on the metrics used to relate them. We show that the way in which balance is interpreted, achieved and maintained influences temperature outcomes. Achieving and maintaining net-zero CO2-equivalent emissions conventionally calculated using GWP100 (100-year global warming potential) and including substantial positive contributions from short-lived climate-forcing agents such as methane would result in a sustained decline in global temperature. A modified approach to the use of GWP100 (that equates constant emissions of short-lived climate forcers with zero sustained emission of CO2) results in global temperatures remaining approximately constant once net-zero CO2-equivalent emissions are achieved and maintained. Our paper provides policymakers with an overview of issues and choices that are important to determine which approach is most appropriate in the context of the Paris Agreement.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.
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Affiliation(s)
- J Fuglestvedt
- CICERO Center for International Climate Research, PO Box 1129, Blindern, 0318 Oslo, Norway
| | - J Rogelj
- Energy Program, International Institute for Applied Systems Analysis (IIASA), 2361 Laxenburg, Austria
- Institute for Atmospheric and Climate Science, ETH Zurich, Universitätstrasse 16, 8006 Zurich, Switzerland
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK
| | - R J Millar
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK
| | - M Allen
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK
- Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | - O Boucher
- Institut Pierre-Simon Laplace, Sorbonne Université, CNRS, Paris, France
| | - M Cain
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK
- Oxford Martin School, University of Oxford, 34 Broad Street, Oxford OX1 3BD, UK
| | - P M Forster
- School of Earth and Environment, Maths/Earth and Environment Building, University of Leeds, Leeds LS2 9JT, UK
| | - E Kriegler
- Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, PO Box 601203, 14412 Potsdam, Germany
| | - D Shindell
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
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23
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Richardson TB, Forster PM, Andrews T, Boucher O, Faluvegi G, Fläschner D, Kasoar M, Kirkevåg A, Lamarque JF, Myhre G, Olivié D, Samset BH, Shawki D, Shindell D, Takemura T, Voulgarakis A. Carbon dioxide physiological forcing dominates projected Eastern Amazonian drying. Geophys Res Lett 2018; 45:2815-2825. [PMID: 33041385 PMCID: PMC7546038 DOI: 10.1002/2017gl076520] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Future projections of east Amazonian precipitation indicate drying, but they are uncertain and poorly understood. In this study we analyse the Amazonian precipitation response to individual atmospheric forcings using a number of global climate models. Black carbon is found to drive reduced precipitation over the Amazon due to temperature-driven circulation changes, but the magnitude is uncertain. CO2 drives reductions in precipitation concentrated in the east, mainly due to a robustly negative, but highly variable in magnitude, fast response. We find that the physiological effect of CO2 on plant stomata is the dominant driver of the fast response due to reduced latent heating, and also contributes to the large model spread. Using a simple model we show that CO2 physiological effects dominate future multi-model mean precipitation projections over the Amazon. However, in individual models temperature-driven changes can be large, but due to little agreement, they largely cancel out in the model-mean.
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Affiliation(s)
| | | | - T Andrews
- Met Office Hadley Centre, United Kingdom
| | - O Boucher
- Institut Pierre-Simon Laplace, Université Pierre et Marie Curie / CNRS, Paris, France
| | - G Faluvegi
- NASA Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, USA
| | - D Fläschner
- Max-Planck-Institut für Meteorologie, Hamburg, Germany
| | - M Kasoar
- Imperial College London, London, United Kingdom
| | - A Kirkevåg
- Norwegian Meteorological Institute, Oslo, Norway
| | | | - G Myhre
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - D Olivié
- Norwegian Meteorological Institute, Oslo, Norway
| | - B H Samset
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - D Shawki
- Imperial College London, London, United Kingdom
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24
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Shindell D, Borgford-Parnell N, Brauer M, Haines A, Kuylenstierna JCI, Leonard SA, Ramanathan V, Ravishankara A, Amann M, Srivastava L. A climate policy pathway for near- and long-term benefits. Science 2018; 356:493-494. [PMID: 28473553 DOI: 10.1126/science.aak9521] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- D Shindell
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA.
| | - N Borgford-Parnell
- Institute for Governance and Sustainable Development, Washington, DC 20008, USA
| | - M Brauer
- School of Population and Public Health, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - A Haines
- London School of Hygiene and Tropical Medicine, London WCIH 9SH, UK
| | | | - S A Leonard
- United Nations Environment Programme, 75015 Paris, France
| | - V Ramanathan
- Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA
| | | | - M Amann
- International Institute for Applied Systems Analysis, Laxenburg, A-2361 Austria
| | - L Srivastava
- TERI University, Vasant Kunj, New Delhi 110 070, India
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25
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Shindell D, Faluvegi G, Seltzer K, Shindell C. Quantified, Localized Health Benefits of Accelerated Carbon Dioxide Emissions Reductions. Nat Clim Chang 2018; 8:291-295. [PMID: 29623109 PMCID: PMC5880221 DOI: 10.1038/s41558-018-0108-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Societal risks increase as Earth warms, but also for emissions trajectories accepting relatively high levels of near-term emissions while assuming future negative emissions will compensate even if they lead to identical warming [1]. Accelerating carbon dioxide (CO2) emissions reductions, including as a substitute for negative emissions, hence reduces long-term risks but requires dramatic near-term societal transformations [2]. A major barrier to emissions reductions is the difficulty of reconciling immediate, localized costs with global, long-term benefits [3, 4]. However, 2°C trajectories not relying on negative emissions or 1.5°C trajectories require elimination of most fossil fuel related emissions. This generally reduces co-emissions that cause ambient air pollution, resulting in near-term, localized health benefits. We therefore examine the human health benefits of increasing ambition of 21st century CO2 reductions by 180 GtC; an amount that would shift a 'standard' 2°C scenario to 1.5°C or could achieve 2°C without negative emissions. The decreased air pollution leads to 153±43 million fewer premature deaths worldwide, with ~40% occurring during the next 40 years, and minimal climate disbenefits. More than a million premature deaths would be prevented in many metropolitan areas in Asia and Africa, and >200,000 in individual urban areas on every inhabited continent except Australia.
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Affiliation(s)
- Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, NC 27708
- Duke Global Health Initiative, Duke University, Durham, NC 27708
| | - Greg Faluvegi
- Center for Climate Systems Research, Columbia University and NASA Goddard Institute for Space Studies, New York, NY 10025
| | - Karl Seltzer
- Nicholas School of the Environment, Duke University, Durham, NC 27708
| | - Cary Shindell
- Civil and Environmental Engineering, Duke University, Durham, NC 27708
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26
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Stjern CW, Samset BH, Myhre G, Forster PM, Hodnebrog Ø, Andrews T, Boucher O, Faluvegi G, Iversen T, Kasoar M, Kharin V, Kirkevåg A, Lamarque JF, Olivié D, Richardson T, Shawki D, Shindell D, Smith CJ, Takemura T, Voulgarakis A. Rapid adjustments cause weak surface temperature response to increased black carbon concentrations. J Geophys Res Atmos 2017; Volume 122:11462-11481. [PMID: 32441705 PMCID: PMC7241673 DOI: 10.1002/2017jd027326] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We investigate the climate response to increased concentrations of black carbon (BC), as part of the Precipitation Driver Response Model Intercomparison Project (PDRMIP). A tenfold increase in BC is simulated by 9 global coupled-climate models, producing a model-median effective radiative forcing (ERF) of 0.82 (ranging from 0.41 to 2.91) Wm-2, and a warming of 0.67 (0.16 to 1.66) K globally and 1.24 (0.26 to 4.31) K in the Arctic. A strong positive instantaneous radiative forcing (median of 2.10 Wm-2 based on five of the models) is countered by negative rapid adjustments (-0.64 Wm-2 for the same five models), which dampen the total surface temperature signal. Unlike other drivers of climate change, the response of temperature and cloud profiles to the BC forcing is dominated by rapid adjustments. Low-level cloud amounts increase for all models, while higher-level clouds are diminished. The rapid temperature response is particularly strong above 400 hPa, where increased atmospheric stabilization and reduced cloud cover contrast the response pattern of the other drivers. In conclusion, we find that this substantial increase in BC concentrations does have considerable impacts on important aspects of the climate system. However, some of these effects tend to offset one another, leaving a relatively small global warming of 0.47 K per Wm-2 - about 20 % lower than the response to a doubling of CO2. Translating the tenfold increase in BC to the present-day impact of anthropogenic BC (given the emissions used in this work) would leave a warming of merely 0.07 K.
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Affiliation(s)
- Camilla Weum Stjern
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | - Gunnar Myhre
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | - Øivind Hodnebrog
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | - Olivier Boucher
- Institut Pierre-Simon Laplace, Univ. P et M. Curie / CNRS, Paris, France
| | - Gregory Faluvegi
- Center for Climate Systems Research, Columbia University, New York, USA
- NASA Goddard Institute for Space Studies, New York, USA
| | | | | | - Viatcheslav Kharin
- Canadian Centre for Climate Modelling and Analysis, Victoria, BC, Canada
| | - Alf Kirkevåg
- Norwegian Meteorological Institute, Oslo, Norway
| | | | - Dirk Olivié
- Norwegian Meteorological Institute, Oslo, Norway
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27
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Kumar R, Mishra V, Buzan J, Kumar R, Shindell D, Huber M. Dominant control of agriculture and irrigation on urban heat island in India. Sci Rep 2017; 7:14054. [PMID: 29070866 PMCID: PMC5656645 DOI: 10.1038/s41598-017-14213-2] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/05/2017] [Indexed: 11/22/2022] Open
Abstract
As is true in many regions, India experiences surface Urban Heat Island (UHI) effect that is well understood, but the causes of the more recently discovered Urban Cool Island (UCI) effect remain poorly constrained. This raises questions about our fundamental understanding of the drivers of rural-urban environmental gradients and hinders development of effective strategies for mitigation and adaptation to projected heat stress increases in rapidly urbanizing India. Here we show that more than 60% of Indian urban areas are observed to experience a day-time UCI. We use satellite observations and the Community Land Model (CLM) to identify the impact of irrigation and prove for the first time that UCI is caused by lack of vegetation and moisture in non-urban areas relative to cities. In contrast, urban areas in extensively irrigated landscapes generally experience the expected positive UHI effect. At night, UHI warming intensifies, occurring across a majority (90%) of India’s urban areas. The magnitude of rural-urban temperature contrasts is largely controlled by agriculture and moisture availability from irrigation, but further analysis of model results indicate an important role for atmospheric aerosols. Thus both land-use decisions and aerosols are important factors governing, modulating, and even reversing the expected urban-rural temperature gradients.
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Affiliation(s)
- Rahul Kumar
- Civil Engineering, Indian Institute of Technology Gandhinagar, Gujarat, 382355, India
| | - Vimal Mishra
- Civil Engineering, Indian Institute of Technology Gandhinagar, Gujarat, 382355, India.
| | - Jonathan Buzan
- Earth, Atmospheric and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Rohini Kumar
- UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | | | - Matthew Huber
- Earth, Atmospheric and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
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28
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Archer-Nicholls S, Archibald A, Arnold S, Bartels-Rausch T, Brown S, Carpenter LJ, Collins W, Conibear L, Doherty R, Dunmore R, Edebeli J, Edwards M, Evans M, Finlayson-Pitts B, Hamilton J, Hastings M, Heald C, Heard D, Kalberer M, Kampf C, Kiendler-Scharr A, Knopf D, Kroll J, Lacey F, Lelieveld J, Marais E, Murphy J, Olawoyin O, Ravishankara A, Reid J, Rudich Y, Shindell D, Unger N, Wahner A, Wallington TJ, Williams J, Young P, Zelenyuk A. The air we breathe: Past, present, and future: general discussion. Faraday Discuss 2017; 200:501-527. [PMID: 28795728 DOI: 10.1039/c7fd90040f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Archibald A, Arnold S, Bejan L, Brown S, Brüggemann M, Carpenter LJ, Collins W, Evans M, Finlayson-Pitts B, George C, Hastings M, Heard D, Hewitt CN, Isaacman-VanWertz G, Kalberer M, Keutsch F, Kiendler-Scharr A, Knopf D, Lelieveld J, Marais E, Petzold A, Ravishankara A, Reid J, Rovelli G, Scott C, Sherwen T, Shindell D, Tinel L, Unger N, Wahner A, Wallington TJ, Williams J, Young P, Zelenyuk A. Atmospheric chemistry and the biosphere: general discussion. Faraday Discuss 2017; 200:195-228. [PMID: 28795727 DOI: 10.1039/c7fd90038d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Myhre G, Forster PM, Samset BH, Hodnebrog Ø, Sillmann J, Aalbergsjø SG, Andrews T, Boucher O, Faluvegi G, Fläschner D, Iversen T, Kasoar M, Kharin V, Lamarque JF, Olivié D, Richardson T, Shindell D, Shine KP, Stjern CW, Takemura T, Voulgarakis A, Zwiers F. PDRMIP: A Precipitation Driver and Response Model Intercomparison Project, Protocol and preliminary results. Bull Am Meteorol Soc 2017; 98:1185-1198. [PMID: 32713957 PMCID: PMC7380094 DOI: 10.1175/bams-d-16-0019.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
As the global temperature increases with changing climate, precipitation rates and patterns are affected through a wide range of physical mechanisms. The globally averaged intensity of extreme precipitation also changes more rapidly than the globally averaged precipitation rate. While some aspects of the regional variation in precipitation predicted by climate models appear robust, there is still a large degree of inter-model differences unaccounted for. Individual drivers of climate change initially alter the energy budget of the atmosphere leading to distinct rapid adjustments involving changes in precipitation. Differences in how these rapid adjustment processes manifest themselves within models are likely to explain a large fraction of the present model spread and needs better quantifications to improve precipitation predictions. Here, we introduce the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), where a set of idealized experiments designed to understand the role of different climate forcing mechanisms were performed by a large set of climate models. PDRMIP focuses on understanding how precipitation changes relating to rapid adjustments and slower responses to climate forcings are represented across models. Initial results show that rapid adjustments account for large regional differences in hydrological sensitivity across multiple drivers. The PDRMIP results are expected to dramatically improve our understanding of the causes of the present diversity in future climate projections.
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Affiliation(s)
- G Myhre
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | - B H Samset
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - Ø Hodnebrog
- CICERO Center for International Climate and Environmental Research - Oslo Norway
| | - J Sillmann
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - S G Aalbergsjø
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | - T Andrews
- Met Office Hadley Centre, Exeter, UK
| | - O Boucher
- Laboratoire de Météorologie Dynamique, IPSL, Univ. P et M. Curie / CNRS, Paris, France
| | | | - D Fläschner
- Max-Planck-Institut fur Meteorologie, Hamburg Germany
| | - T Iversen
- Norwegian Meteorological Institute, Oslo, Norway
| | - M Kasoar
- Imperial College London, London, United Kingdom
| | - V Kharin
- Canadian Centre for Climate Modelling and Analysis, Victoria, BC, Canada A. Kirkevåg, Norwegian Meteorological Institute, Oslo, Norway
| | | | - D Olivié
- Norwegian Meteorological Institute, Oslo, Norway
| | | | | | - K P Shine
- University of Reading, Reading, United Kingdom
| | - Camilla W Stjern
- CICERO Center for International Climate and Environmental Research - Oslo, Norway
| | | | | | - F Zwiers
- Pacific Climate Impacts Consortium University of Victoria, Canada
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Westervelt DM, Conley AJ, Fiore AM, Lamarque JF, Shindell D, Previdi M, Faluvegi G, Correa G, Horowitz LW. Multimodel precipitation responses to removal of U.S. sulfur dioxide emissions. J Geophys Res Atmos 2017; 122:5024-5038. [PMID: 33005557 PMCID: PMC7526610 DOI: 10.1002/2017jd026756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Emissions of aerosols and their precursors are declining due to policies enacted to protect human health, yet we currently lack a full understanding of the magnitude, spatiotemporal pattern, statistical significance, and physical mechanisms of precipitation responses to aerosol reductions. We quantify the global and regional precipitation responses to U.S. SO2 emission reductions using three fully coupled chemistry-climate models: Community Earth System Model version 1, Geophysical Fluid Dynamics Laboratory Coupled Model 3, and Goddard Institute for Space Studies ModelE2. We contrast 200 year (or longer) simulations in which anthropogenic U.S. sulfur dioxide (SO2) emissions are set to zero with present-day control simulations to assess the aerosol, cloud, and precipitation response to U.S. SO2 reductions. In all three models, reductions in aerosol optical depth up to 70% and cloud droplet number column concentration up to 60% occur over the eastern U.S. and extend over the Atlantic Ocean. Precipitation responses occur both locally and remotely, with the models consistently showing an increase in most regions considered. We find a northward shift of the tropical rain belt location of up to 0.35° latitude especially near the Sahel, where the rainy season length and intensity are significantly enhanced in two of the three models. This enhancement is the result of greater warming in the Northern versus Southern Hemispheres, which acts to shift the Intertropical Convergence Zone northward, delivering additional wet season rainfall to the Sahel. Two of our three models thus imply a previously unconsidered benefit of continued U.S. SO2 reductions for Sahel precipitation.
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Affiliation(s)
- D. M. Westervelt
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
- NASA Goddard Institute for Space Studies, New York, New York, USA
| | - A. J. Conley
- National Center for Atmospheric Research, Boulder, Colorado, USA
| | - A. M. Fiore
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
- Department of Earth and Environmental Sciences, Columbia University, Palisades, New York, USA
| | - J.-F. Lamarque
- National Center for Atmospheric Research, Boulder, Colorado, USA
| | - D. Shindell
- Nicholas School of the Environment, Duke University, Durham, North Carolina, USA
| | - M. Previdi
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
| | - G. Faluvegi
- NASA Goddard Institute for Space Studies, New York, New York, USA
- Center for Climate Systems Research, Columbia University, New York, New York, USA
| | - G. Correa
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA
| | - L. W. Horowitz
- Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, New Jersey, USA
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Geller MA, Zhou T, Shindell D, Ruedy R, Aleinov I, Nazarenko L, Tausnev NL, Kelley M, Sun S, Cheng Y, Field RD, Faluvegi G. Modeling the QBO-Improvements resulting from higher-model vertical resolution. J Adv Model Earth Syst 2016; 8:1092-1105. [PMID: 27917258 PMCID: PMC5114865 DOI: 10.1002/2016ms000699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 06/07/2016] [Indexed: 06/06/2023]
Abstract
Using the NASA Goddard Institute for Space Studies (GISS) climate model, it is shown that with proper choice of the gravity wave momentum flux entering the stratosphere and relatively fine vertical layering of at least 500 m in the upper troposphere-lower stratosphere (UTLS), a realistic stratospheric quasi-biennial oscillation (QBO) is modeled with the proper period, amplitude, and structure down to tropopause levels. It is furthermore shown that the specified gravity wave momentum flux controls the QBO period whereas the width of the gravity wave momentum flux phase speed spectrum controls the QBO amplitude. Fine vertical layering is required for the proper downward extension to tropopause levels as this permits wave-mean flow interactions in the UTLS region to be resolved in the model. When vertical resolution is increased from 1000 to 500 m, the modeled QBO modulation of the tropical tropopause temperatures increasingly approach that from observations, and the "tape recorder" of stratospheric water vapor also approaches the observed. The transport characteristics of our GISS models are assessed using age-of-air and N2O diagnostics, and it is shown that some of the deficiencies in model transport that have been noted in previous GISS models are greatly improved for all of our tested model vertical resolutions. More realistic tropical-extratropical transport isolation, commonly referred to as the "tropical pipe," results from the finer vertical model layering required to generate a realistic QBO.
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Affiliation(s)
- Marvin A. Geller
- School of Marine and Atmospheric SciencesStony Brook UniversityStony BrookNew YorkUSA
| | - Tiehan Zhou
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Center for Climate Systems Research, Columbia UniversityNew YorkNew YorkUSA
| | - D. Shindell
- Earth and Ocean SciencesNicholas School of the Environment, Duke UniversityDurhamNorth CarolinaUSA
| | - R. Ruedy
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Trinnovim LLCNew YorkNew YorkUSA
| | - I. Aleinov
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Center for Climate Systems Research, Columbia UniversityNew YorkNew YorkUSA
| | - L. Nazarenko
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Center for Climate Systems Research, Columbia UniversityNew YorkNew YorkUSA
| | - N. L. Tausnev
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Trinnovim LLCNew YorkNew YorkUSA
| | - M. Kelley
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Trinnovim LLCNew YorkNew YorkUSA
| | - S. Sun
- NOAA/Earth System Research LaboratoryBoulderColoradoUSA
| | - Y. Cheng
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Center for Climate Systems Research, Columbia UniversityNew YorkNew YorkUSA
| | - R. D. Field
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Department of Applied Physics and Applied MathematicsColumbia UniversityNew YorkNew YorkUSA
| | - G. Faluvegi
- NASA Goddard Institute for Space StudiesNew YorkNew YorkUSA
- Center for Climate Systems Research, Columbia UniversityNew YorkNew YorkUSA
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Affiliation(s)
- Noah Scovronick
- Global Change and Sustainability Research Institute, University of the Witwatersrand, Braamfontein, Johannesburg, South Africa
| | - Carlos Dora
- Department of Public Health, Environmental and Social Determinants of Health, WHO, Geneva, Switzerland
| | - Elaine Fletcher
- Department of Public Health, Environmental and Social Determinants of Health, WHO, Geneva, Switzerland
| | - Andy Haines
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London WC1H 9SH, UK.
| | - Drew Shindell
- Nicholas School of the Environment, Duke University, Durham, NC, USA
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Anenberg SC, Schwartz J, Shindell D, Amann M, Faluvegi G, Klimont Z, Janssens-Maenhout G, Pozzoli L, Van Dingenen R, Vignati E, Emberson L, Muller NZ, West JJ, Williams M, Demkine V, Hicks WK, Kuylenstierna J, Raes F, Ramanathan V. Global air quality and health co-benefits of mitigating near-term climate change through methane and black carbon emission controls. Environ Health Perspect 2012; 120:831-9. [PMID: 22418651 PMCID: PMC3385429 DOI: 10.1289/ehp.1104301] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 03/14/2012] [Indexed: 05/20/2023]
Abstract
BACKGROUND Tropospheric ozone and black carbon (BC), a component of fine particulate matter (PM ≤ 2.5 µm in aerodynamic diameter; PM(2.5)), are associated with premature mortality and they disrupt global and regional climate. OBJECTIVES We examined the air quality and health benefits of 14 specific emission control measures targeting BC and methane, an ozone precursor, that were selected because of their potential to reduce the rate of climate change over the next 20-40 years. METHODS We simulated the impacts of mitigation measures on outdoor concentrations of PM(2.5) and ozone using two composition-climate models, and calculated associated changes in premature PM(2.5)- and ozone-related deaths using epidemiologically derived concentration-response functions. RESULTS We estimated that, for PM(2.5) and ozone, respectively, fully implementing these measures could reduce global population-weighted average surface concentrations by 23-34% and 7-17% and avoid 0.6-4.4 and 0.04-0.52 million annual premature deaths globally in 2030. More than 80% of the health benefits are estimated to occur in Asia. We estimated that BC mitigation measures would achieve approximately 98% of the deaths that would be avoided if all BC and methane mitigation measures were implemented, due to reduced BC and associated reductions of nonmethane ozone precursor and organic carbon emissions as well as stronger mortality relationships for PM(2.5) relative to ozone. Although subject to large uncertainty, these estimates and conclusions are not strongly dependent on assumptions for the concentration-response function. CONCLUSIONS In addition to climate benefits, our findings indicate that the methane and BC emission control measures would have substantial co-benefits for air quality and public health worldwide, potentially reversing trends of increasing air pollution concentrations and mortality in Africa and South, West, and Central Asia. These projected benefits are independent of carbon dioxide mitigation measures. Benefits of BC measures are underestimated because we did not account for benefits from reduced indoor exposures and because outdoor exposure estimates were limited by model spatial resolution.
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Affiliation(s)
- Susan C Anenberg
- U.S. Environmental Protection Agency, Washington, DC 20460, USA.
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Shindell D, Kuylenstierna JCI, Vignati E, van Dingenen R, Amann M, Klimont Z, Anenberg SC, Muller N, Janssens-Maenhout G, Raes F, Schwartz J, Faluvegi G, Pozzoli L, Kupiainen K, Höglund-Isaksson L, Emberson L, Streets D, Ramanathan V, Hicks K, Oanh NTK, Milly G, Williams M, Demkine V, Fowler D. Simultaneously mitigating near-term climate change and improving human health and food security. Science 2012; 335:183-9. [PMID: 22246768 DOI: 10.1126/science.1210026] [Citation(s) in RCA: 294] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide-reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold.
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Affiliation(s)
- Drew Shindell
- NASA Goddard Institute for Space Studies and Columbia Earth Institute, Columbia University, New York, NY 10025, USA.
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Callaghan TV, Johansson M, Brown RD, Groisman PY, Labba N, Radionov V, Barry RG, Bulygina ON, Essery RLH, Frolov DM, Golubev VN, Grenfell TC, Petrushina MN, Razuvaev VN, Robinson DA, Romanov P, Shindell D, Shmakin AB, Sokratov SA, Warren S, Yang D. The Changing Face of Arctic Snow Cover: A Synthesis of Observed and Projected Changes. Ambio 2011; 40:17-31. [PMCID: PMC3357780 DOI: 10.1007/s13280-011-0212-y] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Analysis of in situ and satellite data shows evidence of different regional snow cover responses to the widespread warming and increasing winter precipitation that has characterized the Arctic climate for the past 40–50 years. The largest and most rapid decreases in snow water equivalent (SWE) and snow cover duration (SCD) are observed over maritime regions of the Arctic with the highest precipitation amounts. There is also evidence of marked differences in the response of snow cover between the North American and Eurasian sectors of the Arctic, with the North American sector exhibiting decreases in snow cover and snow depth over the entire period of available in situ observations from around 1950, while widespread decreases in snow cover are not apparent over Eurasia until after around 1980. However, snow depths are increasing in many regions of Eurasia. Warming and more frequent winter thaws are contributing to changes in snow pack structure with important implications for land use and provision of ecosystem services. Projected changes in snow cover from Global Climate Models for the 2050 period indicate increases in maximum SWE of up to 15% over much of the Arctic, with the largest increases (15–30%) over the Siberian sector. In contrast, SCD is projected to decrease by about 10–20% over much of the Arctic, with the smallest decreases over Siberia (<10%) and the largest decreases over Alaska and northern Scandinavia (30–40%) by 2050. These projected changes will have far-reaching consequences for the climate system, human activities, hydrology, and ecology.
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Affiliation(s)
| | - Margareta Johansson
- Department of Earth and Ecosystem Sciences, Division of Physical Geography and Ecosystem Analyses, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
| | - Ross D. Brown
- Climate Research Division of Environment Canada, Ouranos Climate Consortium, c/o Ouranos, 550 Sherbrooke St. West, 19th Floor, Montreal, QC H3A 1B9 Canada
| | - Pavel Ya. Groisman
- NOAA/NESDIS National Climatic Data Center, Veach-Baley Federal Building, 151 Patton Avenue, Asheville, NC 28801-5001 USA
| | - Niklas Labba
- Gáisi Sámi Centre, Lakselvbukt, 9042 Laksvatn, Norway
| | - Vladimir Radionov
- AARI, 38 Bering Str., Saint Petersburg, The Russian Federation 199397
| | - Roger G. Barry
- NSIDC/CIRES, University of Colorado, Boulder, CO 80309-0449 USA
| | - Olga N. Bulygina
- Climatology Department, All-Russian Research Institute of Hydrometeorological Information—World Data Centre (RIHMI-WDC), 6 Koroleva Street, Obninsk, Kaluga Region, The Russian Federation 249035
| | | | - D. M. Frolov
- Laboratory of Snow Avalanches and Mudflows, Faculty of Geography, Moscow State University, Leninskie Gory, 1, Moscow, The Russian Federation 119991
| | - Vladimir N. Golubev
- Laboratory of Snow Avalanches and Mudflows, Faculty of Geography, Moscow State University, Leninskie Gory, 1, Moscow, The Russian Federation 119991
| | - Thomas C. Grenfell
- Department of Atmospheric Sciences, MS 351640, University of Washington, Seattle, WA 98195-1640 USA
| | - Marina N. Petrushina
- Department of Physical Geography and Landscapes, Faculty of Geography, Moscow State University, Leninskie Gory, 1, Moscow, The Russian Federation 119991
| | | | - David A. Robinson
- Department of Geography, Rutgers University, 54 Joyce Kilmer Avenue, Piscataway, NJ 08854 USA
| | - Peter Romanov
- NOAA/NESDIS World Weather Building Rm. 711, 5200 Auth Rd., Camp Springs, MD 20746 USA
| | - Drew Shindell
- NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025 USA
| | - Andrey B. Shmakin
- Institute of Geography, 29 Staromonetny St., Moscow, The Russian Federation 119017
| | - Sergey A. Sokratov
- Faculty of Geography, Natural Risks Assessment Laboratory, Moscow State University, GSP-1, Leninskiye Gory 1, Moscow, The Russian Federation 119991
| | - Stephen Warren
- Department of Atmospheric Sciences, and of Earth & Space Sciences, University of Washington, Seattle, WA 98195-1640 USA
| | - Daquing Yang
- Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK USA
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Shindell D, Schulz M, Ming Y, Takemura T, Faluvegi G, Ramaswamy V. Spatial scales of climate response to inhomogeneous radiative forcing. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd014108] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mann ME, Zhang Z, Rutherford S, Bradley RS, Hughes MK, Shindell D, Ammann C, Faluvegi G, Ni F. Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly. Science 2009; 326:1256-60. [PMID: 19965474 DOI: 10.1126/science.1177303] [Citation(s) in RCA: 237] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Global temperatures are known to have varied over the past 1500 years, but the spatial patterns have remained poorly defined. We used a global climate proxy network to reconstruct surface temperature patterns over this interval. The Medieval period is found to display warmth that matches or exceeds that of the past decade in some regions, but which falls well below recent levels globally. This period is marked by a tendency for La Niña–like conditions in the tropical Pacific. The coldest temperatures of the Little Ice Age are observed over the interval 1400 to 1700 C.E., with greatest cooling over the extratropical Northern Hemisphere continents. The patterns of temperature change imply dynamical responses of climate to natural radiative forcing changes involving El Niño and the North Atlantic Oscillation–Arctic Oscillation.
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Affiliation(s)
- Michael E Mann
- Department of Meteorology and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA.
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Robock A, Ammann CM, Oman L, Shindell D, Levis S, Stenchikov G. Did the Toba volcanic eruption of ∼74 ka B.P. produce widespread glaciation? ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jd011652] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Pendergast D, Shindell D, Cerretelli P, Rennie D. Role of Central and Peripheral Circulatory Adjustments in Oxygen Transport at the Onset of Exercise. Int J Sports Med 2008. [DOI: 10.1055/s-2008-1034654] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
I investigate the potential for sudden climate change during the current century. This investigation takes into account evidence from the Earth's history, from climate models and our understanding of the physical processes governing climate shifts. Sudden alterations to climate forcing seem to be improbable, with sudden changes instead most likely to arise from climate feedbacks. Based on projections from models validated against historical events, dramatic changes in ocean circulation appear unlikely. Ecosystem-climate feedbacks clearly have the potential to induce sudden change, but are relatively poorly understood at present. More probable sudden changes are large increases in the frequency of summer heatwaves and changes resulting from feedbacks involving hydrology. These include ice sheet decay, which may be set in motion this century. The most devastating consequences are likely to occur further in the future, however. Reductions in subtropical precipitation are likely to be the most severe hydrologic effects this century, with rapid changes due to the feedbacks of relatively well-understood large-scale circulation patterns. Water stress may become particularly acute in the Southwest US and Mexico, and in the Mediterranean and Middle East, where rainfall decreases of 10-25% (regionally) and up to 40% (locally) are projected.
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Affiliation(s)
- Drew Shindell
- NASA Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY 10025, USA.
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Dentener F, Stevenson D, Ellingsen K, Van Noije T, Schultz M, Amann M, Atherton C, Bell N, Bergmann D, Bey I, Bouwman L, Butler T, Cofala J, Collins B, Drevet J, Doherty R, Eickhout B, Eskes H, Fiore A, Gauss M, Hauglustaine D, Horowitz L, Isaksen ISA, Josse B, Lawrence M, Krol M, Lamarque JF, Montanaro V, Müller JF, Peuch VH, Pitari G, Pyle J, Rast S, Rodriguez I, Sanderson M, Savage NH, Shindell D, Strahan S, Szopa S, Sudo K, Van Dingenen R, Wild O, Zeng G. The global atmospheric environment for the next generation. Environ Sci Technol 2006; 40:3586-94. [PMID: 16786698 DOI: 10.1021/es0523845] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Air quality, ecosystem exposure to nitrogen deposition, and climate change are intimately coupled problems: we assess changes in the global atmospheric environment between 2000 and 2030 using 26 state-of-the-art global atmospheric chemistry models and three different emissions scenarios. The first (CLE) scenario reflects implementation of current air quality legislation around the world, while the second (MFR) represents a more optimistic case in which all currently feasible technologies are applied to achieve maximum emission reductions. We contrast these scenarios with the more pessimistic IPCC SRES A2 scenario. Ensemble simulations for the year 2000 are consistent among models and show a reasonable agreement with surface ozone, wet deposition, and NO2 satellite observations. Large parts of the world are currently exposed to high ozone concentrations and high deposition of nitrogen to ecosystems. By 2030, global surface ozone is calculated to increase globally by 1.5 +/- 1.2 ppb (CLE) and 4.3 +/- 2.2 ppb (A2), using the ensemble mean model results and associated +/-1 sigma standard deviations. Only the progressive MFR scenario will reduce ozone, by -2.3 +/- 1.1 ppb. Climate change is expected to modify surface ozone by -0.8 +/- 0.6 ppb, with larger decreases over sea than over land. Radiative forcing by ozone increases by 63 +/- 15 and 155 +/- 37 mW m(-2) for CLE and A2, respectively, and decreases by -45 +/- 15 mW m(-2) for MFR. We compute that at present 10.1% of the global natural terrestrial ecosystems are exposed to nitrogen deposition above a critical load of 1 g N m(-2) yr(-1). These percentages increase by 2030 to 15.8% (CLE), 10.5% (MFR), and 25% (A2). This study shows the importance of enforcing current worldwide air quality legislation and the major benefits of going further. Nonattainment of these air quality policy objectives, such as expressed by the SRES-A2 scenario, would further degrade the global atmospheric environment.
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Affiliation(s)
- F Dentener
- Joint Research Centre, Institute for Environment and Sustainability, via E. Fermi 1, 1-21020, Ispra, Italy.
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Shindell D, Faluvegi G, Lacis A, Hansen J, Ruedy R, Aguilar E. Role of tropospheric ozone increases in 20th-century climate change. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006348] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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45
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Affiliation(s)
- Drew Shindell
- NASA-Goddard Institute for Space Studies, New York, NY 10025, USA.
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Abstract
Results from a global climate model including an interactive parameterization of stratospheric chemistry show how upper stratospheric ozone changes may amplify observed, 11-year solar cycle irradiance changes to affect climate. In the model, circulation changes initially induced in the stratosphere subsequently penetrate into the troposphere, demonstrating the importance of the dynamical coupling between the stratosphere and troposphere. The model reproduces many observed 11-year oscillations, including the relatively long record of geopotential height variations; hence, it implies that these oscillations are likely driven, at least in part, by solar variability.
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Affiliation(s)
- D Shindell
- NASA Goddard Institute for Space Studies (GISS) and Center for Climate Systems Research, Columbia University, 2880 Broadway, New York, NY 10025, USA. E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375, USA
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Cerretelli P, Shindell D, Pendergast DP, Di Prampero PE, Rennie DW. Oxygen uptake transients at the onset and offset of arm and leg work. Respir Physiol 1977; 30:81-97. [PMID: 877453 DOI: 10.1016/0034-5687(77)90023-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The halftimes (t1/2) of the VO2 on-and off-responses have been determined on 4 moderately active subjects (1) in arm cranking (VO2 congruent to 1 1/min). (2) in leg pedaling at 4 graded submaximal (VO2 congruent to 0.8 to 2.51/min) work loads, and (3) when superimposing arm cranking on preexisting leg pedaling, both in the supine and in the upright position. In supine experiments the mean t1/2 of the VO2 on-response was longer for arm cranking than for leg pedaling (64 vs 44-49 sec) at equal VO2; however, at the same percentage of arm and leg VO2 max the respective t1/2 were similar. In sitting experiments all t1/2 of the VO2 on-response were shorter than when supine, but the t1/2 for the arms were still slightly longer than those for the legs. When arm cranking was superimposed on preexisting leg pedaling, the t1/4 for arms was reduced both in supine (from 64 to 35-38 sec) and in the sitting position (from 44 to 40 sec). The halftime of the VO2 off-response were much shorter (20-32 sec) than those of the on-response and similar in all experiments. In all conditions the O2 deficits at work onset were considerably larger than the fast component of the corresponding O2 debts during the first minutes of recovery. The difference was totally accounted for by anaerobic glycolysis occurring early during the VO2 on-response, particularly in arm exercise. It is concluded that at submaximal work loads the O2 deficit is accounted for the fast component of the O2 debt plus the O2 equivalent of the early lactate production.
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Bishop B, Hoffman H, Wallis I, Shindell D. Effects of increased ambient pressure and nitrogen on man's monosynaptic reflexes. J Appl Physiol (1985) 1975; 38:86-90. [PMID: 122822 DOI: 10.1152/jappl.1975.38.1.86] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neurological signs during dives may result from altered excitability of central neurons. The present study assesses the effect of an increase in pressure from 1 to 3 ATA on the excitability of muscle spindles and alpha motoneurons by comparing the EMG amplitudes of the mechanically and electrically elicited monosynaptic reflexes of the gastrocnemius-soleus muscle in 10 normal adults breathing a normoxic oxygen-nitrogen gas mixture. At the surface the amplitude of the electrically elicited H response was matched to that of the mechanically elicited Achilles tendon reflex (ATR), but at depth these amplitudes became significantly different. In every subject the amplitude of the ATR, which depends upon the excitability of both muscle spindles and the alpha motoneurons, was reduced on an average of 38% (with a range of 12-75%). The H response bypasses the muscle spindles and hence, depends primarily upon alpha motoneuron excitability. Its amplitude was unaltered in four, reduced in three, and increased in three subjects. Since the ATR was always depressed despite the direction of change in the H response, we have concluded that an increase in ambient pressure (i.e., pressure per se, or nitrogen, or both) must have decreased the responsiveness of muscle spindles to the tendon tap via a reduction in fusimotor activity.
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