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Sadavarte P, Pandey S, Maasakkers JD, Lorente A, Borsdorff T, Denier van der Gon H, Houweling S, Aben I. Rebuttal to Correspondence on "Methane Emissions from Superemitting Coal Mines in Australia Quantified Using TROPOMI Satellite Observations". Environ Sci Technol 2024; 58:5629-5630. [PMID: 38457526 DOI: 10.1021/acs.est.4c01510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/10/2024]
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2
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Naus S, Maasakkers JD, Gautam R, Omara M, Stikker R, Veenstra AK, Nathan B, Irakulis-Loitxate I, Guanter L, Pandey S, Girard M, Lorente A, Borsdorff T, Aben I. Assessing the Relative Importance of Satellite-Detected Methane Superemitters in Quantifying Total Emissions for Oil and Gas Production Areas in Algeria. Environ Sci Technol 2023; 57:19545-19556. [PMID: 37956986 DOI: 10.1021/acs.est.3c04746] [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] [Indexed: 11/21/2023]
Abstract
Methane emissions from oil and gas production provide an important contribution to global warming. We investigate 2020 emissions from the largest gas field in Algeria, Hassi R'Mel, and the oil-production-dominated area Hassi Messaoud. We use methane data from the high-resolution (20 m) Sentinel-2 instruments to identify and estimate emission time series for 11 superemitters (including 10 unlit flares). We integrate this information in a transport model inversion that uses methane data from the coarser (7 km × 5.5 km) but higher-precision TROPOMI instrument to estimate emissions from both the 11 superemitters (>1 t/h individually) and the remaining diffuse area source (not detected as point sources with Sentinel-2). Compared to a bottom-up inventory for 2019 that is aligned with UNFCCC-reported emissions, we find that 2020 emissions in Hassi R'Mel (0.16 [0.11-0.22] Tg/yr) are lower by 53 [24-73]%, and emissions in Hassi Messaoud (0.22 [0.13-0.28] Tg/yr) are higher by 79 [4-188]%. Our analysis indicates that a larger fraction of Algeria's methane emissions (∼75%) come from oil production than national reporting suggests (5%). Although in both regions the diffuse area source constitutes the majority of emissions, relatively few satellite-detected superemitters provide a significant contribution (24 [12-40]% in Hassi R'Mel; 49 [27-71]% in Hassi Messaoud), indicating that mitigation efforts should address both. Our synergistic use of Sentinel-2 and TROPOMI can produce a unique and detailed emission characterization of oil and gas production areas.
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Affiliation(s)
- S Naus
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - J D Maasakkers
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - R Gautam
- Environmental Defense Fund, Washington, District of Columbia 20009, United States
| | - M Omara
- Environmental Defense Fund, Washington, District of Columbia 20009, United States
| | - R Stikker
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - A K Veenstra
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - B Nathan
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - I Irakulis-Loitxate
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politécnica de Valéncia (UPV), Valencia 46022, Spain
- International Methane Emission Observatory, United Nations Environment Program, Paris 75015, France
| | - L Guanter
- Environmental Defense Fund, Washington, District of Columbia 20009, United States
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politécnica de Valéncia (UPV), Valencia 46022, Spain
| | - S Pandey
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91011, United States
| | - M Girard
- GHGSat Inc., Montréal H2W 1Y5, Canada
| | - A Lorente
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
- Environmental Defense Fund, Washington, District of Columbia 20009, United States
| | - T Borsdorff
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
| | - I Aben
- SRON Netherlands Institute for Space Research, Leiden 3584 CA, Netherlands
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3
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Zheng B, Ciais P, Chevallier F, Yang H, Canadell JG, Chen Y, van der Velde IR, Aben I, Chuvieco E, Davis SJ, Deeter M, Hong C, Kong Y, Li H, Li H, Lin X, He K, Zhang Q. Record-high CO 2 emissions from boreal fires in 2021. Science 2023. [PMID: 36862792 DOI: 10.1126/science.ade0805] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Extreme wildfires are becoming more common and increasingly affecting Earth's climate. Wildfires in boreal forests have attracted much less attention than those in tropical forests, although boreal forests are one of the most extensive biomes on Earth and are experiencing the fastest warming. We used a satellite-based atmospheric inversion system to monitor fire emissions in boreal forests. Wildfires are rapidly expanding into boreal forests with emerging warmer and drier fire seasons. Boreal fires, typically accounting for 10% of global fire carbon dioxide emissions, contributed 23% (0.48 billion metric tons of carbon) in 2021, by far the highest fraction since 2000. 2021 was an abnormal year because North American and Eurasian boreal forests synchronously experienced their greatest water deficit. Increasing numbers of extreme boreal fires and stronger climate-fire feedbacks challenge climate mitigation efforts.
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Affiliation(s)
- Bo Zheng
- Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.,State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Philippe Ciais
- Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.,Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France.,The Cyprus Institute, Nicosia 2121, Cyprus
| | - Frederic Chevallier
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Hui Yang
- Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, 07745 Jena, Germany
| | | | - Yang Chen
- Department of Earth System Science, University of California, Irvine, Irvine, CA 92697, USA
| | - Ivar R van der Velde
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands.,Department of Earth Sciences, Vrije Universiteit, Amsterdam, Netherlands
| | - Ilse Aben
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands.,Department of Physics and Astronomy, Vrije Universiteit, Amsterdam, Netherlands
| | - Emilio Chuvieco
- Universidad de Alcalá, Environmental Remote Sensing Research Group, Department of Geology, Geography and the Environment, 28801 Alcalá de Henares, Spain
| | - Steven J Davis
- Department of Earth System Science, University of California, Irvine, Irvine, CA 92697, USA.,Department of Civil and Environmental Engineering, University of California, Irvine, Irvine, CA 92697, USA
| | - Merritt Deeter
- Atmospheric Chemistry Observations and Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO 80307 USA
| | - Chaopeng Hong
- Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.,State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Yawen Kong
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China
| | - Haiyan Li
- School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Hui Li
- Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xin Lin
- Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Kebin He
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.,State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Qiang Zhang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China
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4
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Maasakkers JD, Varon DJ, Elfarsdóttir A, McKeever J, Jervis D, Mahapatra G, Pandey S, Lorente A, Borsdorff T, Foorthuis LR, Schuit BJ, Tol P, van Kempen TA, van Hees R, Aben I. Using satellites to uncover large methane emissions from landfills. Sci Adv 2022; 8:eabn9683. [PMID: 35947659 PMCID: PMC9365275 DOI: 10.1126/sciadv.abn9683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
As atmospheric methane concentrations increase at record pace, it is critical to identify individual emission sources with high potential for mitigation. Here, we leverage the synergy between satellite instruments with different spatiotemporal coverage and resolution to detect and quantify emissions from individual landfills. We use the global surveying Tropospheric Monitoring Instrument (TROPOMI) to identify large emission hot spots and then zoom in with high-resolution target-mode observations from the GHGSat instrument suite to identify the responsible facilities and characterize their emissions. Using this approach, we detect and analyze strongly emitting landfills (3 to 29 t hour-1) in Buenos Aires, Delhi, Lahore, and Mumbai. Using TROPOMI data in an inversion, we find that city-level emissions are 1.4 to 2.6 times larger than reported in commonly used emission inventories and that the landfills contribute 6 to 50% of those emissions. Our work demonstrates how complementary satellites enable global detection, identification, and monitoring of methane superemitters at the facility level.
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Affiliation(s)
| | - Daniel J. Varon
- Harvard University, Cambridge, MA, USA
- GHGSat Inc., Montréal, Quebec, Canada
| | | | | | | | - Gourav Mahapatra
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | - Sudhanshu Pandey
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | - Alba Lorente
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | - Tobias Borsdorff
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | | | - Berend J. Schuit
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
- GHGSat Inc., Montréal, Quebec, Canada
| | - Paul Tol
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | | | - Richard van Hees
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
| | - Ilse Aben
- SRON Netherlands Institute for Space Research, Leiden, Netherlands
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5
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Irakulis-Loitxate I, Guanter L, Maasakkers JD, Zavala-Araiza D, Aben I. Satellites Detect Abatable Super-Emissions in One of the World's Largest Methane Hotspot Regions. Environ Sci Technol 2022; 56:2143-2152. [PMID: 35102741 PMCID: PMC9940854 DOI: 10.1021/acs.est.1c04873] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Reduction of fossil fuel-related methane emissions has been identified as an essential means for climate change mitigation, but emission source identification remains elusive for most oil and gas production basins in the world. We combine three complementary satellite data sets to survey single methane emission sources on the west coast of Turkmenistan, one of the largest methane hotspots in the world. We found 29 different emitters, with emission rates >1800 kg/h, active in the 2017-2020 time period, although older satellite data show that this type of emission has been occurring for decades. We find that all sources are linked to extraction fields mainly dedicated to crude oil production, where 24 of them are inactive flares venting gas. The analysis of time series suggests a causal relationship between the decrease in flaring and the increase in venting. At the regional level, 2020 shows a substantial increase in the number of methane plume detections concerning previous years. Our results suggest that these large venting point sources represent a key mitigation opportunity as they emanate from human-controlled facilities, and that new satellite methods promise a revolution in the detection and monitoring of methane point emissions worldwide.
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Affiliation(s)
- Itziar Irakulis-Loitxate
- Research
Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València
(UPV), Valencia 46022, Spain
| | - Luis Guanter
- Research
Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València
(UPV), Valencia 46022, Spain
| | | | - Daniel Zavala-Araiza
- Environmental
Defense Fund, Reguliersgracht
79, Amsterdam 1017 LN, The Netherlands
- Institute
for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht 3584 CC, The Netherlands
| | - Ilse Aben
- SRON
Netherlands Institute for Space Research, Utrecht 3584 CA, The Netherlands
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6
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Sadavarte P, Pandey S, Maasakkers JD, Lorente A, Borsdorff T, Denier van der Gon H, Houweling S, Aben I. Methane Emissions from Superemitting Coal Mines in Australia Quantified Using TROPOMI Satellite Observations. Environ Sci Technol 2021; 55:16573-16580. [PMID: 34842427 PMCID: PMC8698155 DOI: 10.1021/acs.est.1c03976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Two years of satellite observations were used to quantify methane emissions from coal mines in Queensland, the largest coal-producing state in Australia. The six analyzed surface and underground coal mines are estimated to emit 570 ± 98 Gg a-1 in 2018-2019. Together, they account for 7% of the national coal production while emitting 55 ± 10% of the reported methane emission from coal mining in Australia. Our results indicate that for two of the three locations, our satellite-based estimates are significantly higher than reported to the Australian government. Most remarkably, 40% of the quantified emission came from a single surface mine (Hail Creek) located in a methane-rich coal basin. Our findings call for increased monitoring and investment in methane recovery technologies for both surface and underground mines.
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Affiliation(s)
- Pankaj Sadavarte
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
- Department
of Climate, Air and Sustainability, TNO, 3584 CB Utrecht, The Netherlands
| | - Sudhanshu Pandey
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | | | - Alba Lorente
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | - Tobias Borsdorff
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
| | | | - Sander Houweling
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
- Department
of Earth Sciences, Vrije Universiteit, Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Ilse Aben
- SRON
Netherlands Institute for Space Research, 3584 CA Utrecht, The Netherlands
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7
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Irakulis-Loitxate I, Guanter L, Liu YN, Varon DJ, Maasakkers JD, Zhang Y, Chulakadabba A, Wofsy SC, Thorpe AK, Duren RM, Frankenberg C, Lyon DR, Hmiel B, Cusworth DH, Zhang Y, Segl K, Gorroño J, Sánchez-García E, Sulprizio MP, Cao K, Zhu H, Liang J, Li X, Aben I, Jacob DJ. Satellite-based survey of extreme methane emissions in the Permian basin. Sci Adv 2021; 7:7/27/eabf4507. [PMID: 34193415 PMCID: PMC8245034 DOI: 10.1126/sciadv.abf4507] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 05/13/2021] [Indexed: 05/12/2023]
Abstract
Industrial emissions play a major role in the global methane budget. The Permian basin is thought to be responsible for almost half of the methane emissions from all U.S. oil- and gas-producing regions, but little is known about individual contributors, a prerequisite for mitigation. We use a new class of satellite measurements acquired during several days in 2019 and 2020 to perform the first regional-scale and high-resolution survey of methane sources in the Permian. We find an unexpectedly large number of extreme point sources (37 plumes with emission rates >500 kg hour-1), which account for a range between 31 and 53% of the estimated emissions in the sampled area. Our analysis reveals that new facilities are major emitters in the area, often due to inefficient flaring operations (20% of detections). These results put current practices into question and are relevant to guide emission reduction efforts.
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Affiliation(s)
- Itziar Irakulis-Loitxate
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València (UPV), Valencia, Spain
| | - Luis Guanter
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València (UPV), Valencia, Spain.
| | - Yin-Nian Liu
- CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai, China.
| | - Daniel J Varon
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- GHGSat Inc., Montréal, Quebec, Canada
| | | | - Yuzhong Zhang
- Key Laboratory of Coastal Environment and Resources of Zhejiang Province (KLaCER), School of Engineering, Westlake University, Hangzhou, Zhejiang, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Apisada Chulakadabba
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Steven C Wofsy
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Andrew K Thorpe
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Riley M Duren
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- University of Arizona, Tucson, AZ, USA
| | - Christian Frankenberg
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- California Institute of Technology, Pasadena, CA, USA
| | | | | | - Daniel H Cusworth
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Yongguang Zhang
- International Institute for Earth System Sciences, Nanjing University, Nanjing, China
| | - Karl Segl
- Helmholtz Center Potsdam, GFZ German Research Center for Geosciences, Potsdam, Germany
| | - Javier Gorroño
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València (UPV), Valencia, Spain
| | - Elena Sánchez-García
- Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politècnica de València (UPV), Valencia, Spain
| | - Melissa P Sulprizio
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Kaiqin Cao
- CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai, China
| | - Haijian Zhu
- CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai, China
| | - Jian Liang
- CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai, China
| | - Xun Li
- CAS Key Laboratory of Infrared System Detection and Imaging Technology, Shanghai Institute of Technical Physics, Shanghai, China
| | - Ilse Aben
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
| | - Daniel J Jacob
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
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8
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Zhang Y, Gautam R, Pandey S, Omara M, Maasakkers JD, Sadavarte P, Lyon D, Nesser H, Sulprizio MP, Varon DJ, Zhang R, Houweling S, Zavala-Araiza D, Alvarez RA, Lorente A, Hamburg SP, Aben I, Jacob DJ. Quantifying methane emissions from the largest oil-producing basin in the United States from space. Sci Adv 2020; 6:eaaz5120. [PMID: 32494644 PMCID: PMC7176423 DOI: 10.1126/sciadv.aaz5120] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 03/19/2020] [Indexed: 05/26/2023]
Abstract
Using new satellite observations and atmospheric inverse modeling, we report methane emissions from the Permian Basin, which is among the world's most prolific oil-producing regions and accounts for >30% of total U.S. oil production. Based on satellite measurements from May 2018 to March 2019, Permian methane emissions from oil and natural gas production are estimated to be 2.7 ± 0.5 Tg a-1, representing the largest methane flux ever reported from a U.S. oil/gas-producing region and are more than two times higher than bottom-up inventory-based estimates. This magnitude of emissions is 3.7% of the gross gas extracted in the Permian, i.e., ~60% higher than the national average leakage rate. The high methane leakage rate is likely contributed by extensive venting and flaring, resulting from insufficient infrastructure to process and transport natural gas. This work demonstrates a high-resolution satellite data-based atmospheric inversion framework, providing a robust top-down analytical tool for quantifying and evaluating subregional methane emissions.
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Affiliation(s)
- Yuzhong Zhang
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
- Environmental Defense Fund, Washington, DC 20009, USA
- School of Engineering, Westlake University, Hangzhou, Zhejiang Province, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang Province, China
| | - Ritesh Gautam
- Environmental Defense Fund, Washington, DC 20009, USA
| | - Sudhanshu Pandey
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
| | - Mark Omara
- Environmental Defense Fund, Washington, DC 20009, USA
| | | | - Pankaj Sadavarte
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
- TNO, Department of Climate, Air and Sustainability, Utrecht, Netherlands
| | - David Lyon
- Environmental Defense Fund, Washington, DC 20009, USA
| | - Hannah Nesser
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Melissa P. Sulprizio
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Daniel J. Varon
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Ruixiong Zhang
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
- ClimaCell Inc., 280 Summer Street Floor 8, Boston, MA 02210, USA
| | - Sander Houweling
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
- Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Daniel Zavala-Araiza
- Environmental Defense Fund, Washington, DC 20009, USA
- Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, Netherlands
| | | | - Alba Lorente
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
| | | | - Ilse Aben
- SRON Netherlands Institute for Space Research, Utrecht, Netherlands
| | - Daniel J. Jacob
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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9
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Pandey S, Houweling S, Krol M, Aben I, Monteil G, Nechita-Banda N, Dlugokencky EJ, Detmers R, Hasekamp O, Xu X, Riley WJ, Poulter B, Zhang Z, McDonald KC, White JWC, Bousquet P, Röckmann T. Enhanced methane emissions from tropical wetlands during the 2011 La Niña. Sci Rep 2017; 7:45759. [PMID: 28393869 PMCID: PMC5385533 DOI: 10.1038/srep45759] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [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: 10/18/2016] [Accepted: 03/03/2017] [Indexed: 11/25/2022] Open
Abstract
Year-to-year variations in the atmospheric methane (CH4) growth rate show significant correlation with climatic drivers. The second half of 2010 and the first half of 2011 experienced the strongest La Niña since the early 1980s, when global surface networks started monitoring atmospheric CH4 mole fractions. We use these surface measurements, retrievals of column-averaged CH4 mole fractions from GOSAT, new wetland inundation estimates, and atmospheric δ13C-CH4 measurements to estimate the impact of this strong La Niña on the global atmospheric CH4 budget. By performing atmospheric inversions, we find evidence of an increase in tropical CH4 emissions of ∼6–9 TgCH4 yr−1 during this event. Stable isotope data suggest that biogenic sources are the cause of this emission increase. We find a simultaneous expansion of wetland area, driven by the excess precipitation over the Tropical continents during the La Niña. Two process-based wetland models predict increases in wetland area consistent with observationally-constrained values, but substantially smaller per-area CH4 emissions, highlighting the need for improvements in such models. Overall, tropical wetland emissions during the strong La Niña were at least by 5% larger than the long-term mean.
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Affiliation(s)
- Sudhanshu Pandey
- Institute of Marine and Atmospheric Research Utrecht (IMAU), Utrecht, The Netherlands.,SRON Netherlands institute for Space Research, Utrecht, The Netherlands
| | - Sander Houweling
- Institute of Marine and Atmospheric Research Utrecht (IMAU), Utrecht, The Netherlands.,SRON Netherlands institute for Space Research, Utrecht, The Netherlands
| | - Maarten Krol
- Institute of Marine and Atmospheric Research Utrecht (IMAU), Utrecht, The Netherlands.,SRON Netherlands institute for Space Research, Utrecht, The Netherlands.,Department of Meteorology and Air Quality (MAQ), Wageningen University and Research Centre, WageningenThe Netherlands
| | - Ilse Aben
- SRON Netherlands institute for Space Research, Utrecht, The Netherlands
| | - Guillaume Monteil
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
| | | | | | - Rob Detmers
- SRON Netherlands institute for Space Research, Utrecht, The Netherlands
| | - Otto Hasekamp
- SRON Netherlands institute for Space Research, Utrecht, The Netherlands
| | - Xiyan Xu
- Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA.,CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Beijing, China
| | - William J Riley
- Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Benjamin Poulter
- Institute on Ecosystems and Department of Ecology, Montana State University, Bozeman, USA
| | - Zhen Zhang
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Kyle C McDonald
- City College of New York, City University of New York, New York, NY, USA
| | | | - Philippe Bousquet
- Laboratoire des Sciences du Climatet de l'Environnement (LSCE), Gif-sur-Yvette, France
| | - Thomas Röckmann
- Institute of Marine and Atmospheric Research Utrecht (IMAU), Utrecht, The Netherlands
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Hooghiemstra PB, Krol MC, van Leeuwen TT, van der Werf GR, Novelli PC, Deeter MN, Aben I, Röckmann T. Interannual variability of carbon monoxide emission estimates over South America from 2006 to 2010. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017758] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Schepers D, Guerlet S, Butz A, Landgraf J, Frankenberg C, Hasekamp O, Blavier JF, Deutscher NM, Griffith DWT, Hase F, Kyro E, Morino I, Sherlock V, Sussmann R, Aben I. Methane retrievals from Greenhouse Gases Observing Satellite (GOSAT) shortwave infrared measurements: Performance comparison of proxy and physics retrieval algorithms. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017549] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [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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Tilstra LG, de Graaf M, Aben I, Stammes P. In-flight degradation correction of SCIAMACHY UV reflectances and Absorbing Aerosol Index. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd016957] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [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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Hooghiemstra PB, Krol MC, Bergamaschi P, de Laat ATJ, van der Werf GR, Novelli PC, Deeter MN, Aben I, Röckmann T. Comparing optimized CO emission estimates using MOPITT or NOAA surface network observations. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd017043] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [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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Frankenberg C, Aben I, Bergamaschi P, Dlugokencky EJ, van Hees R, Houweling S, van der Meer P, Snel R, Tol P. Global column-averaged methane mixing ratios from 2003 to 2009 as derived from SCIAMACHY: Trends and variability. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014849] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [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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Butz A, Hasekamp OP, Frankenberg C, Vidot J, Aben I. CH4retrievals from space-based solar backscatter measurements: Performance evaluation against simulated aerosol and cirrus loaded scenes. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd014514] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Butz
- Netherlands Institute for Space Research; Utrecht Netherlands
| | - O. P. Hasekamp
- Netherlands Institute for Space Research; Utrecht Netherlands
| | - C. Frankenberg
- Netherlands Institute for Space Research; Utrecht Netherlands
| | - J. Vidot
- Netherlands Institute for Space Research; Utrecht Netherlands
| | - I. Aben
- Netherlands Institute for Space Research; Utrecht Netherlands
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Abstract
BACKGROUND Stroke patients commonly suffer from neuropsychiatric disorders, such as depression, that negatively influence stroke outcome. Diagnosis, treatment and prevention of post-stroke psychiatric disorders including depression are under debate. OBJECTIVE To study the course of depression after stroke. METHODS One hundred and ninety first-ever stroke patients were screened for depressive symptoms at 1, 3, 6, 9, and 12 months after stroke. Diagnosis of depression was made according to the DSM-IV criteria of major and minor depression. RESULTS Follow-up was completed in 138 patients. The cumulative incidence of post-stroke depression (PSD) in 1 year was 36.2%. One month after stroke the prevalence of PSD was 18.8%. Thirty percent of patients who were depressed in the first three months did not reach cut-off levels on depression screening instruments at the following assessments. In 44% of these patients symptoms recurred. Recurrent cases were older than patients with limited disease. In 40% of PSD patients depression persisted for at least two consecutive following follow-up visits. Persistent cases were more disabled and suffered more often from major depression. CONCLUSION Half of PSD patients become depressed within the first month after stroke. Although most patients recover, a clinician has to be aware that symptoms can recur especially in older patients and that in patients with major depression symptoms may be persistent. In these patients treatment should be considered, whereas in patients with limited disease an observational approach may suffice.
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Affiliation(s)
- A Bour
- Dpt. Neurology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands.
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de Laat ATJ, Gloudemans AMS, Aben I, Schrijver H. Global evaluation of SCIAMACHY and MOPITT carbon monoxide column differences for 2004–2005. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012698] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bour A, Rasquin S, Aben I, Strik J, Boreas A, Crijns H, Limburg M, Verhey F. The symptomatology of post-stroke depression: comparison of stroke and myocardial infarction patients. Int J Geriatr Psychiatry 2009; 24:1134-42. [PMID: 19418490 DOI: 10.1002/gps.2236] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Depression is a frequent problem in stroke patients but, all too often, the problem goes unrecognized. How depression-like symptoms in post-stroke depression (PSD) should be interpreted is still subject to debate. If PSD has a distinct symptom profile of depression accompanying other chronic vascular somatic conditions then this could imply that PSD is a specific disease entity. OBJECTIVE To study whether depressed stroke patients exhibit other signs and symptoms than patients suffering from depression after myocardial infarction (MI). METHODS Depressive signs and symptoms were measured using the Hospital Anxiety and Depression Scale and the 17-item Hamilton Depression Rating Scale. The results of 190 stroke patients were compared with the results of 198 MI patients every 3 months during the first year after the event. RESULTS Depressed stroke patients exhibited more loss of interest, psychomotor retardation, and gastro-intestinal complaints as compared to depressed MI patients. However, in multivariate analyses including both depressed and non-depressed stroke and MI patients, no specific symptom profile was found to differentiate between the two depressive syndromes by looking at the modifying effect of stroke vs MI on the occurrence of specific symptoms in depression. CONCLUSION Although in their clinical presentation, depressed stroke patients exhibit a symptom profile different from depressed MI patients, this is not due to differences in the depressive syndrome in these two patient groups but it reflects differences between stroke and MI patients in general.
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Affiliation(s)
- A Bour
- Department of Neurology, Maastricht University Hospital, Maastricht, The Netherlands
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Frankenberg C, Yoshimura K, Warneke T, Aben I, Butz A, Deutscher N, Griffith D, Hase F, Notholt J, Schneider M, Schrijver H, Röckmann T. Dynamic processes governing lower-tropospheric HDO/H2O ratios as observed from space and ground. Science 2009; 325:1374-7. [PMID: 19745148 DOI: 10.1126/science.1173791] [Citation(s) in RCA: 171] [Impact Index Per Article: 11.4] [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
The hydrological cycle and its response to environmental variability such as temperature changes is of prime importance for climate reconstruction and prediction. We retrieved deuterated water/water (HDO/H2O) abundances using spaceborne absorption spectroscopy, providing an almost global perspective on the near-surface distribution of water vapor isotopologs. We observed an unexpectedly high HDO/H2O seasonality in the inner Sahel region, pointing to a strong isotopic depletion in the subsiding branch of the Hadley circulation and its misrepresentation in general circulation models. An extension of the analysis at high latitudes using ground-based observations of deltaD and a model study shows that dynamic processes can entirely compensate for temperature effects on the isotopic composition of precipitation.
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Affiliation(s)
- Christian Frankenberg
- SRON-Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht, Netherlands.
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Butz A, Hasekamp OP, Frankenberg C, Aben I. Retrievals of atmospheric CO2 from simulated space-borne measurements of backscattered near-infrared sunlight: accounting for aerosol effects. Appl Opt 2009; 48:3322-3336. [PMID: 19543338 DOI: 10.1364/ao.48.003322] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Retrievals of atmospheric carbon dioxide (CO2) from space-borne measurements of backscattered near-infrared sunlight are hampered by aerosol and cirrus cloud scattering effects. We propose a retrieval approach that allows for the retrieval of a few effective aerosol parameters simultaneously with the CO2 total column by parameterizing particle amount, height distribution, and microphysical properties. Two implementations of the proposed method covering different spectral bands are tested for an ensemble of simulated nadir observations for aerosol (and cirrus) loaded scenes over low- and mid-latitudinal land surfaces. The residual aerosol-induced CO(2) errors are mostly below 1% up to aerosol optical thickness 0.5. The proposed methods also perform convincing for scenes where cirrus clouds of optical thickness 0.1 overlay the aerosol.
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Affiliation(s)
- André Butz
- SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands.
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de Laat ATJ, Gloudemans AMS, Aben I, Krol M, Meirink JF, van der Werf GR, Schrijver H. Correction to “Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon monoxide total columns: Statistical evaluation and comparison with chemistry transport model results”. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007jd009378] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [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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de Laat ATJ, Gloudemans AMS, Aben I, Krol M, Meirink JF, van der Werf GR, Schrijver H. Scanning Imaging Absorption Spectrometer for Atmospheric Chartography carbon monoxide total columns: Statistical evaluation and comparison with chemistry transport model results. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd008256] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [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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de Laat ATJ, Landgraf J, Aben I, Hasekamp O, Bregman B. Validation of Global Ozone Monitoring Experiment ozone profiles and evaluation of stratospheric transport in a global chemistry transport model. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2005jd006789] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [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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24
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Aben I, Verhey F. Depression after a cerebrovascular accident. The importance of the integration of neurobiological and psychosocial pathogenic models. Panminerva Med 2006; 48:49-57. [PMID: 16633332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Stroke survivors frequently suffer from depression. Research has focused on the incidence, phenomenology, course and risk factors of poststroke depression (PSD). Special attention has been paid to biological explanatory models, such as the lesion location and vascular depression hypotheses. In addition to such biological approaches, the role of psychosocial factors should not be neglected. This review critically discusses the proceedings in PSD research emphasizing the need for a biopsychosocial approach.
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Affiliation(s)
- I Aben
- Department of Psychiatry and Neuropsychology, Institute of Brain and Behaviour, Maastricht University Hospital, Maastricht, The Netherlands
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Aben I, Lodder J, Honig A, Lousberg R, Boreas A, Verhey F. Focal or generalized vascular brain damage and vulnerability to depression after stroke: a 1-year prospective follow-up study. Int Psychogeriatr 2006; 18:19-35. [PMID: 16403249 DOI: 10.1017/s104161020500270x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Accepted: 09/08/2005] [Indexed: 11/06/2022]
Abstract
BACKGROUND Both the lesion location hypothesis and the vascular depression hypothesis have been proposed to explain the high incidence of depression in stroke patients. However, research studying both hypotheses in a single cohort is, at present, scarce. OBJECTIVE To test the independent effects of lesion location (left hemisphere, anterior region) and of co-occurring generalized vascular damage on the development of depression in the first year after ischemic stroke, while other risk factors for depression are controlled for. METHODS One hundred and ninety consecutive patients with a first-ever, supratentorial infarct were followed up for one year. CT was performed in the acute phase of stroke, while in 75 patients an additional MRI scan was also available. Depression was assessed at 1, 3, 6, 9, and 12 months after stroke using self-rating scales as screening tools and the SCID-I to diagnose depression according to DSM-IV criteria. RESULTS Separate analyses of the lesion location hypothesis and the vascular depression hypothesis failed to reveal significant support for either of these biological models of post-stroke depression. Similar negative results appeared from one overall, multivariate analysis including variables of both focal and generalized vascular brain damage, as well as other non-cerebral risk factors. In addition, level of handicap and neuroticism were independent predictors of depression in this cohort, as has been reported previously. CONCLUSION This study supports neither the lesion location nor the vascular depression hypothesis of post-stroke depression. A biopsychosocial model including both premorbid (prior to stroke) vulnerability factors, such as neuroticism and (family) history of depression, as well as post-stroke stressors, such as level of handicap, may be more appropriate and deserves further study.
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Affiliation(s)
- I Aben
- Department of Psychiatry & Neuropsychology, Institute Brain and Behavior, Maastricht University, Maastricht, Netherlands
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Burnell EE, de Lange CA, Barnhoorn JBS, Aben I, Levelt PF. Molecules with Large-Amplitude Torsional Motion Partially Oriented in a Nematic Liquid Crystal: Ethane and Isotopomers. J Phys Chem A 2005; 109:11027-36. [PMID: 16331947 DOI: 10.1021/jp052817q] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An NMR study on ethane and five isotopomers dissolved in the nematic liquid crystal Merck ZLI 1132 is performed. A consistent set of dipolar and quadrupolar couplings is obtained. The dipolar couplings are corrected for harmonic vibrational effects, while the contribution from the torsional motion is incorporated classically. The corrected dipolar couplings cannot be understood in terms of a reasonable molecular structure unless effects of the reorientation-vibration interaction are taken into account. Assuming that the reorientation-vibration contributions that are known for the methyl group in methyl fluoride are transferable to ethane, excellent agreement between observed and calculated dipolar couplings is obtained on the basis of the ethane gas-phase structure. The observed and calculated deuterium quadrupolar couplings show discrepancies supporting the notion that average electric field gradients are important in liquid-crystal solvents. An important consequence of the transferability of the reorientation-vibration correlation is that in other molecules with a methyl group the same procedure as for ethane can be followed. Inclusion of this effect generally removes the need to interpret changes in observed dipolar couplings in terms of elusive chemical effects.
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Affiliation(s)
- E E Burnell
- Chemistry Department, University of British Columbia, 2036 Main Mall, Vancouver, Canada, V6T 1Z1.
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27
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Aben I, Tanzi CP, Hartmann W, Stam DM, Stammes P. Validation of space-based polarization measurements by use of a single-scattering approximation, with application to the global ozone monitoring experiment. Appl Opt 2003; 42:3610-3619. [PMID: 12833967 DOI: 10.1364/ao.42.003610] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A method is presented for in-flight validation of space-based polarization measurements based on approximation of the direction of polarization of scattered sunlight by the Rayleigh single-scattering value. This approximation is verified by simulations of radiative transfer calculations for various atmospheric conditions. The simulations show locations along an orbit where the scattering geometries are such that the intensities of the parallel and orthogonal polarization components of the light are equal, regardless of the observed atmosphere and surface. The method can be applied to any space-based instrument that measures the polarization of reflected solar light. We successfully applied the method to validate the Global Ozone Monitoring Experiment (GOME) polarization measurements. The error in the GOME's three broadband polarization measurements appears to be approximately 1%.
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Affiliation(s)
- Ilse Aben
- National Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands.
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Aben I, Verhey F, Strik J, Lousberg R, Lodder J, Honig A. A comparative study into the one year cumulative incidence of depression after stroke and myocardial infarction. J Neurol Neurosurg Psychiatry 2003; 74:581-5. [PMID: 12700297 PMCID: PMC1738412 DOI: 10.1136/jnnp.74.5.581] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The high incidence of post-stroke depression has been claimed to reflect a specific, stroke related pathogenesis in which lesion location plays an important role. To substantiate this claim, post-stroke depression should occur more often than depression after another acute, life threatening, disabling disease that does not involve cerebrovascular damage. OBJECTIVES To compare the cumulative one year incidence of depression after stroke and after myocardial infarction, taking into consideration differences in age, sex, and the level of handicap. METHODS In a longitudinal design, 190 first ever stroke patients and 200 first ever myocardial infarction patients were followed up for one year. Depression self rating scales were used as a screening instrument to detect patients with depressive symptoms. Major and minor depression was assessed at one, three, six, nine, and 12 months after stroke or myocardial infarction according to DSM-IV criteria, using the structured clinical interview from DSM-IV. The severity of depressive symptoms was measured with the Hamilton depression rating scale. Level of disability and handicap was rated with the Rankin handicap scale. RESULTS The cumulative one year incidence of major and minor depression was 37.8% in stroke patients and 25% in patients with myocardial infarction (hazard ratio 1.6; p = 0.06). This difference disappeared after controlling for sex, age, and level of handicap. In addition, no differences were found in the severity of depressive symptoms or in the time of onset of the depressive episode after stroke or myocardial infarction. CONCLUSIONS Depression occurs equally often during the first year after stroke and after myocardial infarction when non-specific factors such as sex, age, and level of handicap are taken into account. Thus the relatively high incidence of post-stroke depression seems not to reflect a specific pathogenic mechanism. Further research is needed to investigate whether vascular factors play a common role in the development of depression after stroke and myocardial infarction.
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Affiliation(s)
- I Aben
- Department of Psychiatry and Neuropsychology, Institute Brain and Behaviour, University of Maastricht, Maastricht, Netherlands
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Aben I, Verhey F, Honig A, Lodder J, Lousberg R, Maes M. Research into the specificity of depression after stroke: a review on an unresolved issue. Prog Neuropsychopharmacol Biol Psychiatry 2001; 25:671-89. [PMID: 11383972 DOI: 10.1016/s0278-5846(01)00158-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Iwo decades of research have failed to generate consistent insight into the specificity of poststroke depression (PSD). This is, at least in part, caused by methodological difficulties. Differences in symptom profile between PSD and depression with no or another medical cause were described, but no specific and unequivocal clinical picture has been established so far. Prevalence rates of PSD varied largely between studies. In community based studies using standardised diagnostic instruments for depression, relatively low prevalence rates were reported compared to inpatient or rehabilitation studies. PSD occurs most frequently in the first few months after stroke, while a new incidence peak may occur 2-3 years after stroke. Two systematic reviews on the relation between lesion location and depression did not support the claim that left hemisphere lesions are a risk factor for PSD. A new concept of vascular depression has been proposed, which relates depression in the elderly to acute or chronic damage to the cerebral vascular system. Future efforts should aim at increasing the uniformity of study designs, assessment tools should be further improved for use in cognitively impaired patients and appropriate control groups should be defined to study the characteristic features of PSD.
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Affiliation(s)
- I Aben
- Institute of Brain and Behaviour, Maastricht University, The Netherlands
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Stam DM, De Haan JF, Hovenier JW, Aben I. Detecting radiances in the O2Aband using polarization-sensitive satellite instruments with application to the Global Ozone Monitoring Experiment. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jd900313] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [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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Ubachs W, Aben I, Milan J, Somsen G, Stuiver A, Hogervorst W. Radiative and collisional relaxation of a single rovibrational quantum state of I2:E(0+g, v=8, J=56. Chem Phys 1993. [DOI: 10.1016/0301-0104(93)87013-d] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Aben I, Ubachs W, van der Zwan G, Hogervorst W. Theory of rotational linestrengths for resonant four-wave-mixing processes in gaseous media with application to CARS. Chem Phys 1993. [DOI: 10.1016/0301-0104(93)80046-c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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