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Filonchyk M, Peterson MP, Gusev A, Hu F, Yan H, Zhou L. Measuring air pollution from the 2021 Canary Islands volcanic eruption. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 849:157827. [PMID: 35944626 DOI: 10.1016/j.scitotenv.2022.157827] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 07/16/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
The eruption of the Cumbre Vieja volcano on the island of La Palma (Canary Islands, Spain) began on September 19, 2021 and ended on December 13, 2021. It lasted continuously for 85 days with short periods of calm when lava did not exit the cone of the volcano. Vast amounts of volcanic material, including ash and gases, were emitted into the environment. This research focuses on these emissions. The main objective is to use available open-source data to examine the impact on regional and local air quality. Data from the following sources were used: 1) Copernicus Atmosphere Monitoring Service (CAMS) data was used to track the transfer of volcanic SO2 in the troposphere in early October over long distances from the source of the eruption, including Western and Eastern Europe, across the Atlantic Ocean and the Caribbean; 2) Data from ground monitoring stations measured the concentrations of SO2 and PM10 near the source; 3) AErosol RObotic NETwork (AERONET) data from the La Palma station that showed high Aerosol Optical Depth (AOD) values (over 0.4) during the active phase of emissions on September 24 and 28, as well as on October 3; 4) Ångström Exponent (AE) values indicated the presence of particles of different sizes. On September 24, high AE values (>1.5), showed the presence of fine-mode fraction scattering aerosols such as sulfates; 5) Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data additionally confirmed the presence of sulfate and dust aerosols in the atmosphere over the region. However, the influence of Saharan dust on the atmosphere of the entire region could not be excluded. This research helps forecast air pollution resulting from large-scale volcanic eruptions and associated health risks to humans.
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Affiliation(s)
- Mikalai Filonchyk
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| | - Michael P Peterson
- Department of Geography/Geology, University of Nebraska Omaha, Omaha, NE 68182, USA.
| | - Andrei Gusev
- Francisk Skorina Gomel State University, Gomel 246019, Belarus
| | - Fengning Hu
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China
| | - Haowen Yan
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| | - Liang Zhou
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
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2
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Dubé K, Randel W, Bourassa A, Degenstein D. Tropopause-Level NO x in the Asian Summer Monsoon. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2022GL099848. [PMID: 36246737 PMCID: PMC9539711 DOI: 10.1029/2022gl099848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/19/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Deep convection within the Asian summer monsoon (ASM) transports surface level air into the upper troposphere-lower stratosphere (UTLS). This work aims to understand the distribution of NO2, NO, and NOx in the UTLS ASM anticyclone from satellite measurements. Observations of NO2 from the Optical Spectrograph and InfraRed Imager System, the Atmospheric Chemistry Experiment - Fourier Transform Spectrometer (ACE-FTS), and the Stratospheric Aerosol and Gas Experiment III on the International Space Station are considered. The PRATMO photochemical box model is used to quantify the NOx photochemistry, and to derive the NOx concentration using OSIRIS NO2 and O3 observations. The satellite data show a relative minimum in NO2 over the ASM in the summer months, while the corresponding NO and NOx anomalies are elevated, mainly due to low O3 and cold temperatures within the ASM. The observations within the ASM show reasonable agreement to simulations from the Whole Atmosphere Community Climate Model.
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Affiliation(s)
- Kimberlee Dubé
- Institute of Space and Atmospheric StudiesUniversity of SaskatchewanSaskatoonSKCanada
| | | | - Adam Bourassa
- Institute of Space and Atmospheric StudiesUniversity of SaskatchewanSaskatoonSKCanada
| | - Doug Degenstein
- Institute of Space and Atmospheric StudiesUniversity of SaskatchewanSaskatoonSKCanada
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3
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Tropospheric Volcanic SO2 Mass and Flux Retrievals from Satellite. The Etna December 2018 Eruption. REMOTE SENSING 2021. [DOI: 10.3390/rs13112225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The presence of volcanic clouds in the atmosphere affects air quality, the environment, climate, human health and aviation safety. The importance of the detection and retrieval of volcanic SO2 lies with risk mitigation as well as with the possibility of providing insights into the mechanisms that cause eruptions. Due to their intrinsic characteristics, satellite measurements have become an essential tool for volcanic monitoring. In recent years, several sensors, with different spectral, spatial and temporal resolutions, have been launched into orbit, significantly increasing the effectiveness of the estimation of the various parameters related to the state of volcanic activity. In this work, the SO2 total masses and fluxes were obtained from several satellite sounders—the geostationary (GEO) MSG-SEVIRI and the polar (LEO) Aqua/Terra-MODIS, NPP/NOAA20-VIIRS, Sentinel5p-TROPOMI, MetopA/MetopB-IASI and Aqua-AIRS—and compared to one another. As a test case, the Christmas 2018 Etna eruption was considered. The characteristics of the eruption (tropospheric with low ash content), the large amount of (simultaneously) available data and the different instrument types and SO2 columnar abundance retrieval strategies make this cross-comparison particularly relevant. Results show the higher sensitivity of TROPOMI and IASI and a general good agreement between the SO2 total masses and fluxes obtained from all the satellite instruments. The differences found are either related to inherent instrumental sensitivity or the assumed and/or calculated SO2 cloud height considered as input for the satellite retrievals. Results indicate also that, despite their low revisit time, the LEO sensors are able to provide information on SO2 flux over large time intervals. Finally, a complete error assessment on SO2 flux retrievals using SEVIRI data was realized by considering uncertainties in wind speed and SO2 abundance.
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4
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Kozun MN, Bourassa AE, Degenstein DA, Haley CS, Zheng SH. Adaptation of the polarimetric multi-spectral Aerosol Limb Imager for high altitude aircraft and satellite observations. APPLIED OPTICS 2021; 60:4325-4334. [PMID: 34143121 DOI: 10.1364/ao.419249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 04/22/2021] [Indexed: 06/12/2023]
Abstract
An elegant breadboard prototype of the Aerosol Limb Imager (ALI) has been developed to meet key performance parameters that will meet requirements for the retrieval of aerosol from the upper troposphere and stratosphere from limb scattered sunlight radiance measurements. Similar in concept to previous high altitude balloon-based generations, this instrument pairs a liquid crystal polarization rotator with an acousto-optic tunable filter to capture polarimetric multi-spectral images of the atmospheric limb. This design improves the vertical resolution, signal-to-noise ratio, and athermalization, all of which will facilitate observation from a moving high altitude aircraft platform, which provides a platform analogous to the spatially varying measurements that would be made from a satellite. Finally, a preliminary design is presented for a satellite-based generation of ALI.
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5
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Bian J, Li D, Bai Z, Li Q, Lyu D, Zhou X. Transport of Asian surface pollutants to the global stratosphere from the Tibetan Plateau region during the Asian summer monsoon. Natl Sci Rev 2020; 7:516-533. [PMID: 34692071 PMCID: PMC8288924 DOI: 10.1093/nsr/nwaa005] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/16/2020] [Accepted: 01/18/2020] [Indexed: 11/13/2022] Open
Abstract
Due to its surrounding strong and deep Asian summer monsoon (ASM) circulation and active surface pollutant emissions, surface pollutants are transported to the stratosphere from the Tibetan Plateau region, which may have critical impacts on global climate through chemical, microphysical and radiative processes. This article reviews major recent advances in research regarding troposphere-stratosphere transport from the region of the Tibetan Plateau. Since the discovery of the total ozone valley over the Tibetan Plateau in summer from satellite observations in the early 1990s, new satellite-borne instruments have become operational and have provided significant new information on atmospheric composition. In addition, in situ measurements and model simulations are used to investigate deep convection and the ASM anticyclone, surface sources and pathways, atmospheric chemical transformations and the impact on global climate. Also challenges are discussed for further understanding critical questions on microphysics and microchemistry in clouds during the pathway to the global stratosphere over the Tibetan Plateau.
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Affiliation(s)
- Jianchun Bian
- Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dan Li
- Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Zhixuan Bai
- Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Qian Li
- Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Daren Lyu
- Key Laboratory of Middle Atmosphere and Global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.,College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiuji Zhou
- State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing 100081, China
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6
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Liu M, Huang Y, Hoffmann L, Huang C, Chen P, Heng Y. High-Resolution Source Estimation of Volcanic Sulfur Dioxide Emissions Using Large-Scale Transport Simulations. LECTURE NOTES IN COMPUTER SCIENCE 2020. [PMCID: PMC7304025 DOI: 10.1007/978-3-030-50420-5_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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7
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Stocker M, Ladstädter F, Wilhelmsen H, Steiner AK. Quantifying Stratospheric Temperature Signals and Climate Imprints From Post-2000 Volcanic Eruptions. GEOPHYSICAL RESEARCH LETTERS 2019; 46:12486-12494. [PMID: 31857737 PMCID: PMC6916164 DOI: 10.1029/2019gl084396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/14/2019] [Accepted: 09/20/2019] [Indexed: 06/10/2023]
Abstract
Small volcanic eruptions and their effects have recently come into research focus. While large eruptions are known to strongly affect stratospheric temperature, the impacts of smaller eruptions are hard to quantify because their signals are masked by natural variability. Here, we quantify the temperature signals from small volcanic eruptions between 2002 and 2016 using new vertically resolved aerosol data and precise temperature observations from radio occultation. We find characteristic space-time signals that can be associated with specific eruptions. In the lower stratosphere, robust warming signals are observed, while in the midstratosphere also cooling signals of some eruptions appear. We find that the volcanic contribution to the temperature trend is up to 20%, depending on latitude and altitude. We conclude that detailed knowledge of the vertical structure of volcanic temperature impacts is crucial for comprehensive trend analysis in order to separate natural from anthropogenic temperature changes.
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Affiliation(s)
- Matthias Stocker
- Wegener Center for Climate and Global Change (WEGC)University of GrazGrazAustria
| | - Florian Ladstädter
- Wegener Center for Climate and Global Change (WEGC)University of GrazGrazAustria
- Institute for Geophysics, Astrophysics, and Meteorology/Institute of PhysicsUniversity of GrazGrazAustria
| | - Hallgeir Wilhelmsen
- Wegener Center for Climate and Global Change (WEGC)University of GrazGrazAustria
- FWF‐DK Climate ChangeUniversity of GrazGrazAustria
| | - Andrea K. Steiner
- Wegener Center for Climate and Global Change (WEGC)University of GrazGrazAustria
- Institute for Geophysics, Astrophysics, and Meteorology/Institute of PhysicsUniversity of GrazGrazAustria
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8
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Effects of Anthropogenic and Natural Forcings on the Summer Temperature Variations in East Asia during the 20th Century. ATMOSPHERE 2019. [DOI: 10.3390/atmos10110690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The effects of the emissions of anthropogenic greenhouse gases (GHGs), aerosols, and natural forcing on the summer-mean surface air temperature (TAS) in the East Asia (EA) land surface in the 20th century are analyzed using six-member coupled model inter-comparison project 5 (CMIP5) general circulation model (GCM) ensembles from five single-forcing simulations. The simulation with the observed GHG concentrations and aerosol emissions reproduces well the land-mean EA TAS trend characterized by warming periods in the early (1911–1940; P1) and late (1971–2000; P3) 20th century separated by a cooling period (1941–1970; P2). The warming in P1 is mainly due to the natural variability related to GHG increases and the long-term recovery from volcanic activities in late-19th/early-20th century. The cooling in P2 occurs as the combined cooling by anthropogenic aerosols and increased volcanic eruptions in the 1960s exceeds the warming by the GHG increases and the nonlinear interaction term. In P3, the combined warming by GHGs and the interaction term exceeds the cooling by anthropogenic aerosols to result in the warming. The SW forcing is not driving the TAS increase in P1/P3 as the shortwave (SW) forcing is heavily affected by the increased cloudiness and the longwave (LW) forcing dominates the SW forcing. The LW forcing to TAS cannot be separated from the LW response to TAS, preventing further analyses. The interaction among these forcing affects TAS via largely modifying the atmospheric water cycle, especially in P2 and P3. Key forcing terms on TAS such as the temperature advection related to large-scale circulation changes cannot be analyzed due to the lack of model data.
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9
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Five-S-isotope evidence of two distinct mass-independent sulfur isotope effects and implications for the modern and Archean atmospheres. Proc Natl Acad Sci U S A 2018; 115:8541-8546. [PMID: 30082380 PMCID: PMC6112696 DOI: 10.1073/pnas.1803420115] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Anomalous sulfur isotopic compositions preserved in sedimentary rocks older than ∼2.5 billion years have been widely interpreted as the products of UV photolysis of sulfur dioxide in an anoxic atmosphere and used to track the history of primitive Earth and evolution of early life. In this study, we present strong observational evidence that there is an additional process that produces similar anomalous sulfur isotope signatures. This previously unknown origin not only offers a tool for quantifying the present-day atmospheric sulfur budget and evaluating its influences on climate and public health but also implies that anomalous sulfur isotopic compositions in some of the oldest rocks on Earth might have been produced in a way different from that previously thought. The signature of mass-independent fractionation of quadruple sulfur stable isotopes (S-MIF) in Archean rocks, ice cores, and Martian meteorites provides a unique probe of the oxygen and sulfur cycles in the terrestrial and Martian paleoatmospheres. Its mechanistic origin, however, contains some uncertainties. Even for the modern atmosphere, the primary mechanism responsible for the S-MIF observed in nearly all tropospheric sulfates has not been identified. Here we present high-sensitivity measurements of a fifth sulfur isotope, stratospherically produced radiosulfur, along with all four stable sulfur isotopes in the same sulfate aerosols and a suite of chemical species to define sources and mechanisms on a field observational basis. The five-sulfur-isotope and multiple chemical species analysis approach provides strong evidence that S-MIF signatures in tropospheric sulfates are concomitantly affected by two distinct processes: an altitude-dependent positive 33S anomaly, likely linked to stratospheric SO2 photolysis, and a negative 36S anomaly mainly associated with combustion. Our quadruple stable sulfur isotopic measurements in varying coal samples (formed in the Carboniferous, Permian, and Triassic periods) and in SO2 emitted from combustion display normal 33S and 36S, indicating that the observed negative 36S anomalies originate from a previously unknown S-MIF mechanism during combustion (likely recombination reactions) instead of coal itself. The basic chemical physics of S-MIF in both photolytic and thermal reactions and their interplay, which were not explored together in the past, may be another ingredient for providing deeper understanding of the evolution of Earth’s atmosphere and life’s origin.
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10
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Atmospheric sulfur isotopic anomalies recorded at Mt. Everest across the Anthropocene. Proc Natl Acad Sci U S A 2018; 115:6964-6969. [PMID: 29915076 DOI: 10.1073/pnas.1801935115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Increased anthropogenic-induced aerosol concentrations over the Himalayas and Tibetan Plateau have affected regional climate, accelerated snow/glacier melting, and influenced water supply and quality in Asia. Although sulfate is a predominant chemical component in aerosols and the hydrosphere, the contributions from different sources remain contentious. Here, we report multiple sulfur isotope composition of sedimentary sulfates from a remote freshwater alpine lake near Mount Everest to reconstruct a two-century record of the atmospheric sulfur cycle. The sulfur isotopic anomaly is utilized as a probe for sulfur source apportionment and chemical transformation history. The nineteenth-century record displays a distinct sulfur isotopic signature compared with the twentieth-century record when sulfate concentrations increased. Along with other elemental measurements, the isotopic proxy suggests that the increased trend of sulfate is mainly attributed to enhancements of dust-associated sulfate aerosols and climate-induced weathering/erosion, which overprinted sulfur isotopic anomalies originating from other sources (e.g., sulfates produced in the stratosphere by photolytic oxidation processes and/or emitted from combustion) as observed in most modern tropospheric aerosols. The changes in sulfur cycling reported in this study have implications for better quantification of radiative forcing and snow/glacier melting at this climatically sensitive region and potentially other temperate glacial hydrological systems. Additionally, the unique Δ33S-δ34S pattern in the nineteenth century, a period with extensive global biomass burning, is similar to the Paleoarchean (3.6-3.2 Ga) barite record, potentially providing a deeper insight into sulfur photochemical/thermal reactions and possible volcanic influences on the Earth's earliest sulfur cycle.
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11
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Lelieveld J, Bourtsoukidis E, Brühl C, Fischer H, Fuchs H, Harder H, Hofzumahaus A, Holland F, Marno D, Neumaier M, Pozzer A, Schlager H, Williams J, Zahn A, Ziereis H. The South Asian monsoon-pollution pump and purifier. Science 2018; 361:270-273. [PMID: 29903882 DOI: 10.1126/science.aar2501] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 05/30/2018] [Indexed: 11/02/2022]
Abstract
Air pollution is growing fastest in monsoon-affected South Asia. During the dry winter monsoon, the fumes disperse toward the Indian Ocean, creating a vast pollution haze, but their fate during the wet summer monsoon has been unclear. We performed atmospheric chemistry measurements by aircraft in the Oxidation Mechanism Observations campaign, sampling the summer monsoon outflow in the upper troposphere between the Mediterranean and the Indian Ocean. The measurements, supported by model calculations, show that the monsoon sustains a remarkably efficient cleansing mechanism by which contaminants are rapidly oxidized and deposited to Earth's surface. However, some pollutants are lofted above the monsoon clouds and chemically processed in a reactive reservoir before being redistributed globally, including to the stratosphere.
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Affiliation(s)
- J Lelieveld
- Max Planck Institute for Chemistry, 55128 Mainz, Germany. .,The Cyprus Institute, 1645 Nicosia, Cyprus
| | | | - C Brühl
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - H Fischer
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - H Fuchs
- Institute for Energy and Climate Research, Research Center Jülich, 52425 Jülich, Germany
| | - H Harder
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - A Hofzumahaus
- Institute for Energy and Climate Research, Research Center Jülich, 52425 Jülich, Germany
| | - F Holland
- Institute for Energy and Climate Research, Research Center Jülich, 52425 Jülich, Germany
| | - D Marno
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - M Neumaier
- Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - A Pozzer
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - H Schlager
- Institute of Atmospheric Physics, Germany Aerospace Center, 82234 Oberpfaffenhofen, Germany
| | - J Williams
- Max Planck Institute for Chemistry, 55128 Mainz, Germany.,The Cyprus Institute, 1645 Nicosia, Cyprus
| | - A Zahn
- Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - H Ziereis
- Institute of Atmospheric Physics, Germany Aerospace Center, 82234 Oberpfaffenhofen, Germany
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12
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Lau WKM, Yuan C, Li Z. Origin, Maintenance and Variability of the Asian Tropopause Aerosol Layer (ATAL): The Roles of Monsoon Dynamics. Sci Rep 2018; 8:3960. [PMID: 29500395 PMCID: PMC5834455 DOI: 10.1038/s41598-018-22267-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 02/19/2018] [Indexed: 11/24/2022] Open
Abstract
Using NASA MERRA2 daily data, we investigated the origin, maintenance and variability of the Asian Tropopause Aerosol Layer (ATAL) in relation to variations of the Asia Monsoon Anticyclone (AMA) during the summer of 2008. During May-June, abundant quantities of carbon monoxide (CO), carbonaceous aerosols (CA) and dusts are found in the mid- and upper troposphere over India and China, arising from enhanced biomass burning emissions, as well as westerly transport from the Middle East deserts. During July-August, large quantities of dusts transported from the deserts are trapped and accumulate over the southern and eastern foothills of the Tibetan Plateau. Despite strong precipitation washout, ambient CO, CA and dust are lofted by orographically forced deep convection to great elevations, 12-16 km above sea level, via two key pathways over heavily polluted regions: a) the Himalayas-Gangetic Plain, and b) the Sichuan Basin. Upon entering the upper-troposphere-lower-stratosphere, the pollutants are capped by a stable layer near the tropopause, advected and dispersed by the anticyclonic circulation of AMA, forming the ATAL resembling a planetary-scale "double-stem chimney cloud". The development and variability of the ATAL are strongly linked to the seasonal march and intraseasonal (20-30 days and higher frequency) oscillations of the Asian monsoon.
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Affiliation(s)
- William K M Lau
- Earth System Science Interdisciplinary Center, U. of Maryland, College Park, MD, 20740, USA.
- Department of Atmospheric and Oceanic Sciences, U. of Maryland, College Park, MD, 20740, USA.
| | - Cheng Yuan
- Earth System Science Interdisciplinary Center, U. of Maryland, College Park, MD, 20740, USA
- School of Atmospheric Sciences, Nanjing University, Nanjing, China
| | - Zhanqing Li
- Earth System Science Interdisciplinary Center, U. of Maryland, College Park, MD, 20740, USA
- Department of Atmospheric and Oceanic Sciences, U. of Maryland, College Park, MD, 20740, USA
- State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
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13
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Kim MH, Omar AH, Tackett JL, Vaughan MA, Winker DM, Trepte CR, Hu Y, Liu Z, Poole LR, Pitts MC, Kar J, Magill BE. The CALIPSO Version 4 Automated Aerosol Classification and Lidar Ratio Selection Algorithm. ATMOSPHERIC MEASUREMENT TECHNIQUES 2018; 11:6107-6135. [PMID: 31921372 PMCID: PMC6951257 DOI: 10.5194/amt-11-6107-2018] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) version 4.10 (V4) level 2 aerosol data products, released in November 2016, include substantial improvements to the aerosol subtyping and lidar ratio selection algorithms. These improvements are described along with resulting changes in aerosol optical depth (AOD). The most fundamental change in V4 level 2 aerosol products is a new algorithm to identify aerosol subtypes in the stratosphere. Four aerosol subtypes are introduced for the stratospheric aerosols: polar stratospheric aerosol (PSA), volcanic ash, sulfate/other, and smoke. The tropospheric aerosol subtyping algorithm was also improved by adding the following enhancements: (1) all aerosol subtypes are now allowed over polar regions, whereas the version 3 (V3) algorithm allowed only clean continental and polluted continental aerosols; (2) a new "dusty marine" aerosol subtype is introduced, representing mixtures of dust and marine aerosols near the ocean surface; and (3) the "polluted continental" and "smoke" subtypes have been renamed "polluted continental/smoke" and "elevated smoke", respectively. V4 also revises the lidar ratios for clean marine, dust, clean continental, and elevated smoke subtypes. As a consequence of the V4 updates, the mean 532 nm AOD retrieved by CALIOP has increased by 0.044 (0.036) or 52 % (40 %) for nighttime (daytime). Lidar ratio revisions are the most influential factor for AOD changes from V3 to V4, especially for cloud-free skies. Preliminary validation studies show that the AOD discrepancies between CALIOP and AERONET/MODIS (ocean) are reduced in V4 compared to V3.
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Affiliation(s)
- Man-Hae Kim
- NASA Postdoctoral Program (USRA), Hampton, VA, USA
| | - Ali H. Omar
- NASA Langley Research Center, Hampton, VA, USA
| | | | | | | | | | | | - Zhaoyan Liu
- Science Systems and Applications, Inc., Hampton, VA, USA
| | | | | | - Jayanta Kar
- Science Systems and Applications, Inc., Hampton, VA, USA
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14
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Kim MH, Omar AH, Tackett JL, Vaughan MA, Winker DM, Trepte CR, Hu Y, Liu Z, Poole LR, Pitts MC, Kar J, Magill BE. The CALIPSO Version 4 Automated Aerosol Classification and Lidar Ratio Selection Algorithm. ATMOSPHERIC MEASUREMENT TECHNIQUES 2018; 11:6107-6135. [PMID: 31921372 DOI: 10.1175/2009jtecha1231.1] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) version 4.10 (V4) level 2 aerosol data products, released in November 2016, include substantial improvements to the aerosol subtyping and lidar ratio selection algorithms. These improvements are described along with resulting changes in aerosol optical depth (AOD). The most fundamental change in V4 level 2 aerosol products is a new algorithm to identify aerosol subtypes in the stratosphere. Four aerosol subtypes are introduced for the stratospheric aerosols: polar stratospheric aerosol (PSA), volcanic ash, sulfate/other, and smoke. The tropospheric aerosol subtyping algorithm was also improved by adding the following enhancements: (1) all aerosol subtypes are now allowed over polar regions, whereas the version 3 (V3) algorithm allowed only clean continental and polluted continental aerosols; (2) a new "dusty marine" aerosol subtype is introduced, representing mixtures of dust and marine aerosols near the ocean surface; and (3) the "polluted continental" and "smoke" subtypes have been renamed "polluted continental/smoke" and "elevated smoke", respectively. V4 also revises the lidar ratios for clean marine, dust, clean continental, and elevated smoke subtypes. As a consequence of the V4 updates, the mean 532 nm AOD retrieved by CALIOP has increased by 0.044 (0.036) or 52 % (40 %) for nighttime (daytime). Lidar ratio revisions are the most influential factor for AOD changes from V3 to V4, especially for cloud-free skies. Preliminary validation studies show that the AOD discrepancies between CALIOP and AERONET/MODIS (ocean) are reduced in V4 compared to V3.
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Affiliation(s)
- Man-Hae Kim
- NASA Postdoctoral Program (USRA), Hampton, VA, USA
| | - Ali H Omar
- NASA Langley Research Center, Hampton, VA, USA
| | | | | | | | | | | | - Zhaoyan Liu
- Science Systems and Applications, Inc., Hampton, VA, USA
| | - Lamont R Poole
- Science Systems and Applications, Inc., Hampton, VA, USA
| | | | - Jayanta Kar
- Science Systems and Applications, Inc., Hampton, VA, USA
| | - Brian E Magill
- Science Systems and Applications, Inc., Hampton, VA, USA
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15
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Donovan A, Blundy J, Oppenheimer C, Buisman I. The 2011 eruption of Nabro volcano, Eritrea: perspectives on magmatic processes from melt inclusions. CONTRIBUTIONS TO MINERALOGY AND PETROLOGY. BEITRAGE ZUR MINERALOGIE UND PETROLOGIE 2017; 173:1. [PMID: 31983758 PMCID: PMC6954031 DOI: 10.1007/s00410-017-1425-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 11/14/2017] [Indexed: 06/10/2023]
Abstract
The 2011 eruption of Nabro volcano, Eritrea, produced one of the largest volcanic sulphur inputs to the atmosphere since the 1991 eruption of Mt. Pinatubo, yet has received comparatively little scientific attention. Nabro forms part of an off-axis alignment, broadly perpendicular to the Afar Rift, and has a history of large-magnitude explosive silicic eruptions, as well as smaller more mafic ones. Here, we present and analyse extensive petrological data obtained from samples of trachybasaltic tephra erupted during the 2011 eruption to assess the pre-eruptive magma storage system and explain the large sulphur emission. We show that the eruption involved two texturally distinct batches of magma, one of which was more primitive and richer in sulphur than the other, which was higher in water (up to 2.5 wt%). Modelling of the degassing and crystallisation histories demonstrates that the more primitive magma rose rapidly from depth and experienced degassing crystallisation, while the other experienced isobaric cooling in the crust at around 5 km depth. Interaction between the two batches occurred shortly before the eruption. The eruption itself was likely triggered by recharge-induced destabilisation of vertically extensive mush zone under the volcano. This could potentially account for the large volume of sulphur released. Some of the melt inclusions are volatile undersaturated, and suggest that the original water content of the magma was around 1.3 wt%, which is relatively high for an intraplate setting, but consistent with seismic studies of the Afar plume. This eruption was smaller than some geological eruptions at Nabro, but provides important insights into the plumbing systems and dynamics of off-axis volcanoes in Afar.
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Affiliation(s)
- Amy Donovan
- Department of Geography, King’s College London, London, UK
- Department of Geography, University of Cambridge, Cambridge, UK
| | - Jon Blundy
- School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ UK
| | | | - Iris Buisman
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
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16
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Efficient transport of tropospheric aerosol into the stratosphere via the Asian summer monsoon anticyclone. Proc Natl Acad Sci U S A 2017. [PMID: 28630285 DOI: 10.1073/pnas.1701170114] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An enhanced aerosol layer near the tropopause over Asia during the June-September period of the Asian summer monsoon (ASM) was recently identified using satellite observations. Its sources and climate impact are presently not well-characterized. To improve understanding of this phenomenon, we made in situ aerosol measurements during summer 2015 from Kunming, China, then followed with a modeling study to assess the global significance. The in situ measurements revealed a robust enhancement in aerosol concentration that extended up to 2 km above the tropopause. A climate model simulation demonstrates that the abundant anthropogenic aerosol precursor emissions from Asia coupled with rapid vertical transport associated with monsoon convection leads to significant particle formation in the upper troposphere within the ASM anticyclone. These particles subsequently spread throughout the entire Northern Hemispheric (NH) lower stratosphere and contribute significantly (∼15%) to the NH stratospheric column aerosol surface area on an annual basis. This contribution is comparable to that from the sum of small volcanic eruptions in the period between 2000 and 2015. Although the ASM contribution is smaller than that from tropical upwelling (∼35%), we find that this region is about three times as efficient per unit area and time in populating the NH stratosphere with aerosol. With a substantial amount of organic and sulfur emissions in Asia, the ASM anticyclone serves as an efficient smokestack venting aerosols to the upper troposphere and lower stratosphere. As economic growth continues in Asia, the relative importance of Asian emissions to stratospheric aerosol is likely to increase.
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17
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Thomas BC, Goracke BD, Dalton SM. Atmospheric constituents and surface-level UVB: Implications for a paleoaltimetry proxy and attempts to reconstruct UV exposure during volcanic episodes. EARTH AND PLANETARY SCIENCE LETTERS 2016; 453:141-151. [PMID: 30034018 PMCID: PMC6052448 DOI: 10.1016/j.epsl.2016.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Chemical and morphological features of spores and pollens have been linked to changes in solar ultraviolet radiation (specifically UVB, 280-315 nm) at Earth's surface. Variation in UVB exposure as inferred from these features has been suggested as a proxy for paleoaltitude; such proxies are important in understanding the uplift history of high altitude plateaus, which in turn is important for testing models of the tectonic processes responsible for such uplift. While UVB irradiance does increase with altitude above sea level, a number of other factors affect the irradiance at any given place and time. In this modeling study we use the TUV atmospheric radiative transfer model to investigate dependence of surface-level UVB irradiance and relative biological impact on a number of constituents in Earth's atmosphere that are variable over long and short time periods. We consider changes in O3 column density, and SO2 and sulfate aerosols due to periods of volcanic activity, including that associated with the formation of the Siberian Traps. We find that UVB irradiance may be highly variable under volcanic conditions and variations in several of these atmospheric constituents can easily mimic or overwhelm changes in UVB irradiance due to changes in altitude. On the other hand, we find that relative change with altitude is not very sensitive to different sets of atmospheric conditions. Any paleoaltitude proxy based on UVB exposure requires confidence that the samples under comparison were located at roughly the same latitude, under very similar O3 and SO2 columns, with similar atmospheric aerosol conditions. In general, accurate estimates of the surface-level UVB exposure at any time and location require detailed radiative transfer modeling taking into account a number of atmospheric factors; this result is important for paleoaltitude proxies as well as attempts to reconstruct the UV environment through geologic time and to tie extinctions, such as the end-Permian mass extinction, to UVB irradiance changes.
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Affiliation(s)
- Brian C. Thomas
- Correspondence to: 1700 SW College Ave., Topeka, KS 66604, United States. (B.C. Thomas)
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18
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Gunther T, Schulze M, Friederici A, Theisel H. Visualizing Volcanic Clouds in the Atmosphere and Their Impact on Air Traffic. IEEE COMPUTER GRAPHICS AND APPLICATIONS 2016; 36:36-47. [PMID: 26571518 DOI: 10.1109/mcg.2015.121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Volcanic eruptions are not only hazardous in the direct vicinity of a volcano, but they also affect the climate and air travel for great distances. This article sheds light on the Grímsvötn, Puyehue-Cordón Caulle, and Nabro eruptions in 2011. The authors study the agreement of the complementary satellite data, reconstruct sulfate aerosol and volcanic ash clouds, visualize endangered flight routes, minimize occlusion in particle trajectory visualizations, and focus on the main pathways of Nabro's sulfate aerosol into the stratosphere. The results here were developed for the 2014 IEEE Scientific Visualization Contest, which centers around the fusion of multiple satellite data modalities to reconstruct and assess the movement of volcanic ash and sulfate aerosol emissions. Using data from three volcanic eruptions that occurred in the span of approximately three weeks, the authors study the agreement of the complementary satellite data, reconstruct sulfate aerosol and volcanic ash clouds, visualize endangered flight routes, minimize occlusion in particle trajectory visualizations, and focus on the main pathways of sulfate aerosol into the stratosphere. This video provides animations of the reconstructed ash clouds. https://youtu.be/D9DvJ5AvZAs.
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19
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Nevzorov A, Bazhenov O, Burlakov V, Dolgii S. Certain Results of Measurements of Characteristics of Stratospheric Aerosol Layer and Total Ozone Content at Siberian Lidar Station in Tomsk. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611923007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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20
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21
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Significant radiative impact of volcanic aerosol in the lowermost stratosphere. Nat Commun 2015; 6:7692. [PMID: 26158244 PMCID: PMC4510655 DOI: 10.1038/ncomms8692] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 05/29/2015] [Indexed: 11/15/2022] Open
Abstract
Despite their potential to slow global warming, until recently, the radiative forcing associated with volcanic aerosols in the lowermost stratosphere (LMS) had not been considered. Here we study volcanic aerosol changes in the stratosphere using lidar measurements from the NASA CALIPSO satellite and aircraft measurements from the IAGOS-CARIBIC observatory. Between 2008 and 2012 volcanism frequently affected the Northern Hemisphere stratosphere aerosol loadings, whereas the Southern Hemisphere generally had loadings close to background conditions. We show that half of the global stratospheric aerosol optical depth following the Kasatochi, Sarychev and Nabro eruptions is attributable to LMS aerosol. On average, 30% of the global stratospheric aerosol optical depth originated in the LMS during the period 2008–2011. On the basis of the two independent, high-resolution measurement methods, we show that the LMS makes an important contribution to the overall volcanic forcing. The role played by volcanic-induced cooling in the recent warming hiatus is not accurately described in the latest phase of the Coupled Model Intercomparison Project. Here, the authors use satellite and aircraft data to investigate the radiative impact of volcanic aerosols in the lowermost stratosphere since the year 2000.
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22
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Glantz P, Bourassa A, Herber A, Iversen T, Karlsson J, Kirkevåg A, Maturilli M, Seland Ø, Stebel K, Struthers H, Tesche M, Thomason L. Remote sensing of aerosols in the Arctic for an evaluation of global climate model simulations. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2014; 119:8169-8188. [PMID: 25821664 PMCID: PMC4370760 DOI: 10.1002/jgrd.51507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 06/10/2014] [Indexed: 11/30/2022]
Abstract
In this study Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua retrievals of aerosol optical thickness (AOT) at 555 nm are compared to Sun photometer measurements from Svalbard for a period of 9 years. For the 642 daily coincident measurements that were obtained, MODIS AOT generally varies within the predicted uncertainty of the retrieval over ocean (ΔAOT = ±0.03 ± 0.05 · AOT). The results from the remote sensing have been used to examine the accuracy in estimates of aerosol optical properties in the Arctic, generated by global climate models and from in situ measurements at the Zeppelin station, Svalbard. AOT simulated with the Norwegian Earth System Model/Community Atmosphere Model version 4 Oslo global climate model does not reproduce the observed seasonal variability of the Arctic aerosol. The model overestimates clear-sky AOT by nearly a factor of 2 for the background summer season, while tending to underestimate the values in the spring season. Furthermore, large differences in all-sky AOT of up to 1 order of magnitude are found for the Coupled Model Intercomparison Project phase 5 model ensemble for the spring and summer seasons. Large differences between satellite/ground-based remote sensing of AOT and AOT estimated from dry and humidified scattering coefficients are found for the subarctic marine boundary layer in summer. KEY POINTS Remote sensing of AOT is very useful in validation of climate models.
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Affiliation(s)
- Paul Glantz
- Department of Applied Environmental Science, Stockholm University Stockholm, Sweden
| | - Adam Bourassa
- Institute of Space and Atmospheric Studies, University of Saskatchewan Saskatoon, Saskatchewan, Canada
| | - Andreas Herber
- Alfred Wegener Institute for Polar and Marine Research Bremerhaven, Germany
| | - Trond Iversen
- ECMWF Reading, UK ; Norwegian Meteorological Institute Oslo, Norway
| | | | | | - Marion Maturilli
- Alfred Wegener Institute for Polar and Marine Research Bremerhaven, Germany
| | | | | | - Hamish Struthers
- National Supercomputer Centre, Linköping University Linköping, Sweden
| | - Matthias Tesche
- Department of Applied Environmental Science, Stockholm University Stockholm, Sweden
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23
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Direct observation of spin-forbidden transitions through the use of suitably polarized light. Nat Commun 2014; 5:4126. [DOI: 10.1038/ncomms5126] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 05/14/2014] [Indexed: 11/08/2022] Open
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24
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Lévêque C, Taïeb R, Köppel H. Communication: Theoretical prediction of the importance of the 3B2 state in the dynamics of sulfur dioxide. J Chem Phys 2014; 140:091101. [DOI: 10.1063/1.4867252] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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25
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McCormick BT, Edmonds M, Mather TA, Campion R, Hayer CSL, Thomas HE, Carn SA. Volcano monitoring applications of the Ozone Monitoring Instrument. ACTA ACUST UNITED AC 2013. [DOI: 10.1144/sp380.11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractThe Ozone Monitoring Instrument (OMI) is a satellite-based ultraviolet (UV) spectrometer with unprecedented sensitivity to atmospheric sulphur dioxide (SO2) concentrations. Since late 2004, OMI has provided a high-quality SO2 dataset with near-continuous daily global coverage. In this review, we discuss the principal applications of this dataset to volcano monitoring: (1) the detection and tracking of large eruption clouds, primarily for aviation hazard mitigation; and (2) the use of OMI data for long-term monitoring of volcanic degassing. This latter application is relatively novel, and despite showing some promise, requires further study into a number of key uncertainties. We discuss these uncertainties, and illustrate their potential impact on volcano monitoring with OMI through four new case studies. We also discuss potential future avenues of research using OMI data, with a particular emphasis on the need for greater integration between various monitoring strategies, instruments and datasets.
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Affiliation(s)
- Brendan T. McCormick
- COMET+, National Centre for Earth Observation, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - Marie Edmonds
- COMET+, National Centre for Earth Observation, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - Tamsin A. Mather
- COMET+, National Centre for Earth Observation, Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK
| | - Robin Campion
- Service de Chimie Quantique et Photophysique, Universite Libre de Bruxelles, 50 Ave Roosevelt, CP160/02, 1050 Bruxelles, Belgium
| | - Catherine S. L. Hayer
- COMET+, National Centre for Earth Observation, Environmental Systems Science Centre, University of Reading, Reading RG6 6AL, UK
| | - Helen E. Thomas
- Department of Geological and Mining Sciences and Engineering, Michigan Technological, University, Houghton, Michigan, USA
| | - Simon A. Carn
- Department of Geological and Mining Sciences and Engineering, Michigan Technological, University, Houghton, Michigan, USA
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26
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Vernier JP, Thomason LW, Fairlie TD, Minnis P, Palikonda R, Bedka KM. Comment on "Large Volcanic Aerosol Load in the Stratosphere Linked to Asian Monsoon Transport". Science 2013; 339:647. [DOI: 10.1126/science.1227817] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- J.-P. Vernier
- Science Systems and Applications, Inc., Hampton, VA 23666, USA
| | | | - T. D. Fairlie
- NASA Langley Research Center, Hampton, VA 23681, USA
| | - P. Minnis
- NASA Langley Research Center, Hampton, VA 23681, USA
| | - R. Palikonda
- Science Systems and Applications, Inc., Hampton, VA 23666, USA
| | - K. M. Bedka
- Science Systems and Applications, Inc., Hampton, VA 23666, USA
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27
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Fromm M, Nedoluha G, Charvát Z. Comment on "Large Volcanic Aerosol Load in the Stratosphere Linked to Asian Monsoon Transport". Science 2013; 339:647. [DOI: 10.1126/science.1228605] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Michael Fromm
- Naval Research Laboratory, Washington, DC 20375, USA
| | | | - Zdenek Charvát
- Czech Hydrometeorological Institute, Prague, 143 06, Czech Republic
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28
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Bourassa AE, Robock A, Randel WJ, Deshler T, Rieger LA, Lloyd ND, Llewellyn EJ, Degenstein DA. Response to Comments on "Large Volcanic Aerosol Load in the Stratosphere Linked to Asian Monsoon Transport". Science 2013; 339:647. [DOI: 10.1126/science.1227961] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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