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Hallar AG, Brown SS, Crosman E, Barsanti K, Cappa CD, Faloona I, Fast J, Holmes HA, Horel J, Lin J, Middlebrook A, Mitchell L, Murphy J, Womack CC, Aneja V, Baasandorj M, Bahreini R, Banta R, Bray C, Brewer A, Caulton D, de Gouw J, De Wekker SF, Farmer DK, Gaston CJ, Hoch S, Hopkins F, Karle NN, Kelly JT, Kelly K, Lareau N, Lu K, Mauldin RL, Mallia DV, Martin R, Mendoza D, Oldroyd HJ, Pichugina Y, Pratt KA, Saide P, Silva PJ, Simpson W, Stephens BB, Stutz J, Sullivan A. Coupled Air Quality and Boundary-Layer Meteorology in Western U.S. Basins during Winter: Design and Rationale for a Comprehensive Study. BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY 2021; 0:1-94. [PMID: 34446943 PMCID: PMC8384125 DOI: 10.1175/bams-d-20-0017.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Wintertime episodes of high aerosol concentrations occur frequently in urban and agricultural basins and valleys worldwide. These episodes often arise following development of persistent cold-air pools (PCAPs) that limit mixing and modify chemistry. While field campaigns targeting either basin meteorology or wintertime pollution chemistry have been conducted, coupling between interconnected chemical and meteorological processes remains an insufficiently studied research area. Gaps in understanding the coupled chemical-meteorological interactions that drive high pollution events make identification of the most effective air-basin specific emission control strategies challenging. To address this, a September 2019 workshop occurred with the goal of planning a future research campaign to investigate air quality in Western U.S. basins. Approximately 120 people participated, representing 50 institutions and 5 countries. Workshop participants outlined the rationale and design for a comprehensive wintertime study that would couple atmospheric chemistry and boundary-layer and complex-terrain meteorology within western U.S. basins. Participants concluded the study should focus on two regions with contrasting aerosol chemistry: three populated valleys within Utah (Salt Lake, Utah, and Cache Valleys) and the San Joaquin Valley in California. This paper describes the scientific rationale for a campaign that will acquire chemical and meteorological datasets using airborne platforms with extensive range, coupled to surface-based measurements focusing on sampling within the near-surface boundary layer, and transport and mixing processes within this layer, with high vertical resolution at a number of representative sites. No prior wintertime basin-focused campaign has provided the breadth of observations necessary to characterize the meteorological-chemical linkages outlined here, nor to validate complex processes within coupled atmosphere-chemistry models.
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Affiliation(s)
| | | | - Erik Crosman
- Department of Life, Earth, and Environmental Sciences, West Texas A&M University
| | - Kelley Barsanti
- Department of Chemical and Environmental Engineering, Center for Environmental Research and Technology, University of California, Riverside
| | - Christopher D. Cappa
- Department of Civil and Environmental Engineering, University of California, Davis 95616 USA
| | - Ian Faloona
- Department of Land, Air and Water Resources, University of California, Davis
| | - Jerome Fast
- Atmospheric Science and Global Change Division, Pacific Northwest, National Laboratory, Richland, Washington, USA
| | - Heather A. Holmes
- Department of Chemical Engineering, University of Utah, Salt Lake City, UT
| | - John Horel
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | - John Lin
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | | | - Logan Mitchell
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | - Jennifer Murphy
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Caroline C. Womack
- Cooperative Institute for Research in Environmental Sciences, University of Colorado/ NOAA Chemical Sciences Laboratory, Boulder, CO
| | - Viney Aneja
- Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University
| | | | - Roya Bahreini
- Environmental Sciences, University of California, Riverside, CA
| | | | - Casey Bray
- Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University
| | - Alan Brewer
- NOAA Chemical Sciences Laboratory, Boulder, CO
| | - Dana Caulton
- Department of Atmospheric Science, University of Wyoming
| | - Joost de Gouw
- Cooperative Institute for Research in Environmental Sciences & Department of Chemistry, University of Colorado, Boulder, CO
| | | | | | - Cassandra J. Gaston
- Department of Atmospheric Science - Rosenstiel School of Marine and Atmospheric Science, University of Miami
| | - Sebastian Hoch
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | | | - Nakul N. Karle
- Environmental Science and Engineering, The University of Texas at El Paso, TX
| | - James T. Kelly
- Office of Air Quality Planning and Standards, US Environmental Protection Agency, Research Triangle Park, NC
| | - Kerry Kelly
- Chemical Engineering, University of Utah, Salt Lake City, UT
| | - Neil Lareau
- Atmospheric Sciences and Environmental Sciences and Health, University of Nevada, Reno, NV
| | - Keding Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, Beijing, China, 100871
| | - Roy L. Mauldin
- National Center for Atmospheric Research, Boulder, CO 80307, USA
| | - Derek V. Mallia
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | - Randal Martin
- Civil and Environmental Engineering, Utah State University, Utah Water Research Laboratory, Logan, UT
| | - Daniel Mendoza
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT
| | - Holly J. Oldroyd
- Department of Civil and Environmental Engineering, University of California, Davis
| | | | | | - Pablo Saide
- Department of Atmospheric and Oceanic Sciences, and Institute of the Environment and Sustainability, University of California, Los Angeles
| | - Phillip J. Silva
- Food Animal Environmental Systems Research Unit, USDA-ARS, Bowling Green, KY
| | - William Simpson
- Department of Chemistry, Biochemistry, and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775-6160
| | - Britton B. Stephens
- Earth Observing Laboratory, National Center for Atmospheric Research, Boulder, CO
| | - Jochen Stutz
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles
| | - Amy Sullivan
- Department of Atmospheric Science, Colorado State University, Fort Collins, CO
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Mallia DV, Mitchell LE, Kunik L, Fasoli B, Bares R, Gurney KR, Mendoza DL, Lin JC. Constraining Urban CO 2 Emissions Using Mobile Observations from a Light Rail Public Transit Platform. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15613-15621. [PMID: 33274635 DOI: 10.1021/acs.est.0c04388] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Urban environments are characterized by pronounced spatiotemporal heterogeneity, which can present sampling challenges when utilizing conventional greenhouse gas (GHG) measurement systems. In Salt Lake City, Utah, a GHG instrument was deployed on a light rail train car that continuously traverses the Salt Lake Valley (SLV) through a range of urban typologies. CO2 measurements from a light rail train car were used within a Bayesian inverse modeling framework to constrain urban emissions across the SLV during the fall of 2015. The primary objectives of this study were to (1) evaluate whether ground-based mobile measurements could be used to constrain urban emissions using an inverse modeling framework and (2) quantify the information that mobile observations provided relative to conventional GHG monitoring networks. Preliminary results suggest that ingesting mobile measurements into an inverse modeling framework generated a posterior emission estimate that more closely aligned with observations, reduced posterior emission uncertainties, and extends the geographical extent of emission adjustments.
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Affiliation(s)
- Derek V Mallia
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Logan E Mitchell
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Lewis Kunik
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Ben Fasoli
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Ryan Bares
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Kevin R Gurney
- School of Informatics, Computing and Cyber Systems, Northern Arizona University, Flagstaff, Arizona 86011, United States
| | - Daniel L Mendoza
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
- Pulmonary Division, University of Utah, Salt Lake City, Utah 84112, United States
- Department of City & Metropolitan Planning, University of Utah, Salt Lake City, Utah 84112, United States
| | - John C Lin
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
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3
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Ahn DY, Hansford JR, Howe ST, Ren XR, Salawitch RJ, Zeng N, Cohen MD, Stunder B, Salmon OE, Shepson PB, Gurney KR, Oda T, Lopez-Coto I, Whetstone J, Dickerson RR. Fluxes of Atmospheric Greenhouse-Gases in Maryland (FLAGG-MD): Emissions of Carbon Dioxide in the Baltimore, MD-Washington, D.C. area. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2020; 125:https://doi.org/10.1029/2019jd032004. [PMID: 33094084 PMCID: PMC7577348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To study emissions of CO2 in the Baltimore, MD-Washington, D.C. (Balt-Wash) area, an aircraft campaign was conducted in February 2015, as part of the FLAGG-MD (Fluxes of Atmospheric Greenhouse-Gases in Maryland) project. During the campaign, elevated mole fractions of CO2 were observed downwind of the urban center and local power plants. Upwind flight data and HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model analyses help account for the impact of emissions outside the Balt-Wash area. The accuracy, precision, and sensitivity of CO2 emissions estimates based on the mass balance approach were assessed for both power plants and cities. Our estimates of CO2 emissions from two local power plants agree well with their CEMS (Continuous Emissions Monitoring Systems) records. For the 16 power plant plumes captured by the aircraft, the mean percentage difference of CO2 emissions was -0.3 %. For the Balt-Wash area as a whole, the 1σ CO2 emission rate uncertainty for any individual aircraft-based mass balance approach experiment was ±38 %. Treating the mass balance experiments, which were repeated seven times within nine days, as individual quantifications of the Balt-Wash CO2 emissions, the estimation uncertainty was ±16 % (standard error of the mean at 95% CL). Our aircraft-based estimate was compared to various bottom-up fossil fuel CO2 (FFCO2) emission inventories. Based on the FLAGG-MD aircraft observations, we estimate 1.9±0.3 MtC of FFCO2 from the Balt-Wash area during the month of February 2015. The mean estimate of FFCO2 from the four bottom-up models was 2.2±0.3 MtC.
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Affiliation(s)
- D Y Ahn
- Department of Chemistry and Biochemistry, University of Maryland College Park, Maryland, USA
| | - J R Hansford
- Department of Computer Science, University of Maryland College Park, MD, USA
| | - S T Howe
- Department of Atmospheric and Oceanic Science, University of Maryland College Park, MD, USA
| | - X R Ren
- Department of Atmospheric and Oceanic Science, University of Maryland College Park, MD, USA
- Earth System Science Interdisciplinary Center, University of Maryland College Park, MD, USA
- National Oceanic and Atmospheric Administration Air Resource Laboratory, College Park, MD, USA
| | - R J Salawitch
- Department of Chemistry and Biochemistry, University of Maryland College Park, Maryland, USA
- Department of Atmospheric and Oceanic Science, University of Maryland College Park, MD, USA
- Earth System Science Interdisciplinary Center, University of Maryland College Park, MD, USA
| | - N Zeng
- Department of Atmospheric and Oceanic Science, University of Maryland College Park, MD, USA
- Earth System Science Interdisciplinary Center, University of Maryland College Park, MD, USA
| | - M D Cohen
- National Oceanic and Atmospheric Administration Air Resource Laboratory, College Park, MD, USA
| | - B Stunder
- National Oceanic and Atmospheric Administration Air Resource Laboratory, College Park, MD, USA
| | - O E Salmon
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
| | - P B Shepson
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - K R Gurney
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - T Oda
- Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD, USA
- Goddard Earth Sciences Research and Technology, Universities Space Research Association, Columbia, MD, USA
| | - I Lopez-Coto
- Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - J Whetstone
- Special Programs Office, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - R R Dickerson
- Department of Atmospheric and Oceanic Science, University of Maryland College Park, MD, USA
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4
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Mitchell LE, Lin JC, Bowling DR, Pataki DE, Strong C, Schauer AJ, Bares R, Bush SE, Stephens BB, Mendoza D, Mallia D, Holland L, Gurney KR, Ehleringer JR. Long-term urban carbon dioxide observations reveal spatial and temporal dynamics related to urban characteristics and growth. Proc Natl Acad Sci U S A 2018; 115:2912-2917. [PMID: 29507190 PMCID: PMC5866532 DOI: 10.1073/pnas.1702393115] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cities are concentrated areas of CO2 emissions and have become the foci of policies for mitigation actions. However, atmospheric measurement networks suitable for evaluating urban emissions over time are scarce. Here we present a unique long-term (decadal) record of CO2 mole fractions from five sites across Utah's metropolitan Salt Lake Valley. We examine "excess" CO2 above background conditions resulting from local emissions and meteorological conditions. We ascribe CO2 trends to changes in emissions, since we did not find long-term trends in atmospheric mixing proxies. Three contrasting CO2 trends emerged across urban types: negative trends at a residential-industrial site, positive trends at a site surrounded by rapid suburban growth, and relatively constant CO2 over time at multiple sites in the established, residential, and commercial urban core. Analysis of population within the atmospheric footprints of the different sites reveals approximately equal increases in population influencing the observed CO2, implying a nonlinear relationship with CO2 emissions: Population growth in rural areas that experienced suburban development was associated with increasing emissions while population growth in the developed urban core was associated with stable emissions. Four state-of-the-art global-scale emission inventories also have a nonlinear relationship with population density across the city; however, in contrast to our observations, they all have nearly constant emissions over time. Our results indicate that decadal scale changes in urban CO2 emissions are detectable through monitoring networks and constitute a valuable approach to evaluate emission inventories and studies of urban carbon cycles.
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Affiliation(s)
- Logan E Mitchell
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112;
| | - John C Lin
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
| | - David R Bowling
- Department of Biology, University of Utah, Salt Lake City, UT 84112
| | - Diane E Pataki
- Department of Biology, University of Utah, Salt Lake City, UT 84112
| | - Courtenay Strong
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
| | - Andrew J Schauer
- Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195
| | - Ryan Bares
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
| | - Susan E Bush
- Department of Biology, University of Utah, Salt Lake City, UT 84112
| | | | - Daniel Mendoza
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
| | - Derek Mallia
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
| | - Lacey Holland
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112
- Department of Atmospheric Sciences, University of Hawaii at Manoa, Honolulu, HI 96822
| | - Kevin R Gurney
- School of Life Sciences, Arizona State University, Tempe, AZ 85287
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5
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Patarasuk R, Gurney KR, O’Keeffe D, Song Y, Huang J, Rao P, Buchert M, Lin JC, Mendoza D, Ehleringer JR. Urban high-resolution fossil fuel CO2 emissions quantification and exploration of emission drivers for potential policy applications. Urban Ecosyst 2016. [DOI: 10.1007/s11252-016-0553-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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6
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Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers. PLoS One 2015; 10:e0136237. [PMID: 26302444 PMCID: PMC4547753 DOI: 10.1371/journal.pone.0136237] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 07/30/2015] [Indexed: 11/27/2022] Open
Abstract
Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha-1. As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm2 yr-1. Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha-1 yr-1, a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.
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7
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Gorski G, Strong C, Good SP, Bares R, Ehleringer JR, Bowen GJ. Vapor hydrogen and oxygen isotopes reflect water of combustion in the urban atmosphere. Proc Natl Acad Sci U S A 2015; 112:3247-52. [PMID: 25733906 PMCID: PMC4371996 DOI: 10.1073/pnas.1424728112] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Anthropogenic modification of the water cycle involves a diversity of processes, many of which have been studied intensively using models and observations. Effective tools for measuring the contribution and fate of combustion-derived water vapor in the atmosphere are lacking, however, and this flux has received relatively little attention. We provide theoretical estimates and a first set of measurements demonstrating that water of combustion is characterized by a distinctive combination of H and O isotope ratios. We show that during periods of relatively low humidity and/or atmospheric stagnation, this isotopic signature can be used to quantify the concentration of water of combustion in the atmospheric boundary layer over Salt Lake City. Combustion-derived vapor concentrations vary between periods of atmospheric stratification and mixing, both on multiday and diurnal timescales, and respond over periods of hours to variations in surface emissions. Our estimates suggest that up to 13% of the boundary layer vapor during the period of study was derived from combustion sources, and both the temporal pattern and magnitude of this contribution were closely reproduced by an independent atmospheric model forced with a fossil fuel emissions data product. Our findings suggest potential for water vapor isotope ratio measurements to be used in conjunction with other tracers to refine the apportionment of urban emissions, and imply that water vapor emissions associated with combustion may be a significant component of the water budget of the urban boundary layer, with potential implications for urban climate, ecohydrology, and photochemistry.
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Affiliation(s)
| | - Courtenay Strong
- Department of Atmospheric Sciences, Global Change and Sustainability Center, and
| | | | - Ryan Bares
- Global Change and Sustainability Center, and
| | - James R Ehleringer
- Global Change and Sustainability Center, and Department of Biology, University of Utah, Salt Lake City, UT 84112
| | - Gabriel J Bowen
- Department of Geology & Geophysics, Global Change and Sustainability Center, and
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8
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Ward HC, Kotthaus S, Grimmond CSB, Bjorkegren A, Wilkinson M, Morrison WTJ, Evans JG, Morison JIL, Iamarino M. Effects of urban density on carbon dioxide exchanges: Observations of dense urban, suburban and woodland areas of southern England. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 198:186-200. [PMID: 25613466 DOI: 10.1016/j.envpol.2014.12.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 10/12/2014] [Accepted: 12/26/2014] [Indexed: 05/22/2023]
Abstract
Anthropogenic and biogenic controls on the surface-atmosphere exchange of CO2 are explored for three different environments. Similarities are seen between suburban and woodland sites during summer, when photosynthesis and respiration determine the diurnal pattern of the CO2 flux. In winter, emissions from human activities dominate urban and suburban fluxes; building emissions increase during cold weather, while traffic is a major component of CO2 emissions all year round. Observed CO2 fluxes reflect diurnal traffic patterns (busy throughout the day (urban); rush-hour peaks (suburban)) and vary between working days and non-working days, except at the woodland site. Suburban vegetation offsets some anthropogenic emissions, but 24-h CO2 fluxes are usually positive even during summer. Observations are compared to estimated emissions from simple models and inventories. Annual CO2 exchanges are significantly different between sites, demonstrating the impacts of increasing urban density (and decreasing vegetation fraction) on the CO2 flux to the atmosphere.
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Affiliation(s)
- H C Ward
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK; Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK.
| | - S Kotthaus
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK; Department of Geography, King's College London, London, WC2R 2LS, UK
| | - C S B Grimmond
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
| | - A Bjorkegren
- Department of Geography, King's College London, London, WC2R 2LS, UK
| | - M Wilkinson
- Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey, GU10 4LH, UK
| | - W T J Morrison
- Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
| | - J G Evans
- Centre for Ecology and Hydrology, Wallingford, Oxfordshire, OX10 8BB, UK
| | - J I L Morison
- Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey, GU10 4LH, UK
| | - M Iamarino
- Scuola di Ingegneria, Università degli Studi della Basilicata, 85100, Potenza, Italy
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9
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Font A, Grimmond CSB, Kotthaus S, Morguí JA, Stockdale C, O'Connor E, Priestman M, Barratt B. Daytime CO2 urban surface fluxes from airborne measurements, eddy-covariance observations and emissions inventory in Greater London. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 196:98-106. [PMID: 25463702 DOI: 10.1016/j.envpol.2014.10.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 10/01/2014] [Accepted: 10/04/2014] [Indexed: 06/04/2023]
Abstract
Airborne measurements within the urban mixing layer (360 m) over Greater London are used to quantify CO(2) emissions at the meso-scale. Daytime CO(2) fluxes, calculated by the Integrative Mass Boundary Layer (IMBL) method, ranged from 46 to 104 μmol CO(2) m(-2) s(-1) for four days in October 2011. The day-to-day variability of IMBL fluxes is at the same order of magnitude as for surface eddy-covariance fluxes observed in central London. Compared to fluxes derived from emissions inventory, the IMBL method gives both lower (by 37%) and higher (by 19%) estimates. The sources of uncertainty of applying the IMBL method in urban areas are discussed and guidance for future studies is given.
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10
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Variations in Atmospheric CO2 Mixing Ratios across a Boston, MA Urban to Rural Gradient. LAND 2013. [DOI: 10.3390/land2030304] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Assessment of ground-based atmospheric observations for verification of greenhouse gas emissions from an urban region. Proc Natl Acad Sci U S A 2012; 109:8423-8. [PMID: 22611187 DOI: 10.1073/pnas.1116645109] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
International agreements to limit greenhouse gas emissions require verification to ensure that they are effective and fair. Verification based on direct observation of atmospheric greenhouse gas concentrations will be necessary to demonstrate that estimated emission reductions have been actualized in the atmosphere. Here we assess the capability of ground-based observations and a high-resolution (1.3 km) mesoscale atmospheric transport model to determine a change in greenhouse gas emissions over time from a metropolitan region. We test the method with observations from a network of CO(2) surface monitors in Salt Lake City. Many features of the CO(2) data were simulated with excellent fidelity, although data-model mismatches occurred on hourly timescales due to inadequate simulation of shallow circulations and the precise timing of boundary-layer stratification and destratification. Using two optimization procedures, monthly regional fluxes were constrained to sufficient precision to detect an increase or decrease in emissions of approximately 15% at the 95% confidence level. We argue that integrated column measurements of the urban dome of CO(2) from the ground and/or space are less sensitive than surface point measurements to the redistribution of emitted CO(2) by small-scale processes and thus may allow for more precise trend detection of emissions from urban regions.
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