The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies
The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) is NASAs latest reanalysis for the satellite era (1980-present) using the Goddard Earth Observing System version 5 (GEOS-5) Earth system model. MERRA-2 provides several improvements over its predecessor (MERRA),...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20190027472 2023-05-15T13:07:06+02:00 The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies Darmenov, A. Colarco, P. R. Buchard, V. Beyersdorf, A. J. Yu, H. da Silva, A. M. Ferrare, R. Randles, C. A. Govindaraju, R. Hair, J. Ziemba, L. D. Unclassified, Unlimited, Publicly available July 27, 2017 application/pdf http://hdl.handle.net/2060/20190027472 unknown Document ID: 20190027472 http://hdl.handle.net/2060/20190027472 Copyright, Public use permitted CASI Earth Resources and Remote Sensing NF1676L-24763 Journal of Climate (ISSN 0894-8755) (e-ISSN 1520-0442); 30; 6851-6872 2017 ftnasantrs 2020-02-08T23:47:37Z The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) is NASAs latest reanalysis for the satellite era (1980-present) using the Goddard Earth Observing System version 5 (GEOS-5) Earth system model. MERRA-2 provides several improvements over its predecessor (MERRA), including the inclusion of interactive aerosols for the entire period. In addition to assimilating bias-corrected Aerosol Optical Depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua satellites, it also includes the assimilation of bias-corrected AOD from Advanced Very High Resolution Spectroradiometer (AVHRR) instruments, Multi-angle Imaging SpectroRadiometer (MISR) AOD over bright surfaces, and ground-based Aerosol Robotic Network (AERONET) AOD. This paper is the second of a pair that summarizes our efforts to assess the quality of the MERRA-2 aerosol assimilation. In this study, we first follow previous work performed with version 1 of the MERRA Aerosol Reanalysis (MERRAero) using independent observations. The evaluation of MERRA-2 Absorption Aerosol Optical Depth (AAOD) and ultra-violet Aerosol Index (UV-AI) against the Ozone Monitoring Instrument (OMI) observations show good agreement, particularly over dusty regions where our previous efforts improved model aerosol optical properties. Next, we find that aerosol assimilation system improves the aerosol vertical structure when compared to estimates from the same version of the model without AOD assimilation. A similar conclusion is found for MERRA-2 aerosol surface fine particulate matter (PM (sub 2.5)). However, deficiencies in the forward model such as missing emissions noted during the MERRAero study still explain the MERRA-2 PM(sub 2.5) bias relative to observations over the United States. Finally, to illustrate successes and weaknesses of the AOD assimilation, we focus on the performance of the MERRA-2 aerosol system during several major aerosol events: the Mount Pinatubo eruption in 1991, a Saharan dust event and transportation over the Atlantic Ocean during April 2010, the Rim Fire of summer 2013 in California, and an extreme pollution event over China in January 2013. We conclude with a summary that points to best practices for utilizing the MERRA-2 aerosol reanalysis in future studies. Other/Unknown Material Aerosol Robotic Network NASA Technical Reports Server (NTRS) Merra ENVELOPE(12.615,12.615,65.816,65.816) |
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Open Polar |
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NASA Technical Reports Server (NTRS) |
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ftnasantrs |
language |
unknown |
topic |
Earth Resources and Remote Sensing |
spellingShingle |
Earth Resources and Remote Sensing Darmenov, A. Colarco, P. R. Buchard, V. Beyersdorf, A. J. Yu, H. da Silva, A. M. Ferrare, R. Randles, C. A. Govindaraju, R. Hair, J. Ziemba, L. D. The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
topic_facet |
Earth Resources and Remote Sensing |
description |
The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) is NASAs latest reanalysis for the satellite era (1980-present) using the Goddard Earth Observing System version 5 (GEOS-5) Earth system model. MERRA-2 provides several improvements over its predecessor (MERRA), including the inclusion of interactive aerosols for the entire period. In addition to assimilating bias-corrected Aerosol Optical Depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua satellites, it also includes the assimilation of bias-corrected AOD from Advanced Very High Resolution Spectroradiometer (AVHRR) instruments, Multi-angle Imaging SpectroRadiometer (MISR) AOD over bright surfaces, and ground-based Aerosol Robotic Network (AERONET) AOD. This paper is the second of a pair that summarizes our efforts to assess the quality of the MERRA-2 aerosol assimilation. In this study, we first follow previous work performed with version 1 of the MERRA Aerosol Reanalysis (MERRAero) using independent observations. The evaluation of MERRA-2 Absorption Aerosol Optical Depth (AAOD) and ultra-violet Aerosol Index (UV-AI) against the Ozone Monitoring Instrument (OMI) observations show good agreement, particularly over dusty regions where our previous efforts improved model aerosol optical properties. Next, we find that aerosol assimilation system improves the aerosol vertical structure when compared to estimates from the same version of the model without AOD assimilation. A similar conclusion is found for MERRA-2 aerosol surface fine particulate matter (PM (sub 2.5)). However, deficiencies in the forward model such as missing emissions noted during the MERRAero study still explain the MERRA-2 PM(sub 2.5) bias relative to observations over the United States. Finally, to illustrate successes and weaknesses of the AOD assimilation, we focus on the performance of the MERRA-2 aerosol system during several major aerosol events: the Mount Pinatubo eruption in 1991, a Saharan dust event and transportation over the Atlantic Ocean during April 2010, the Rim Fire of summer 2013 in California, and an extreme pollution event over China in January 2013. We conclude with a summary that points to best practices for utilizing the MERRA-2 aerosol reanalysis in future studies. |
format |
Other/Unknown Material |
author |
Darmenov, A. Colarco, P. R. Buchard, V. Beyersdorf, A. J. Yu, H. da Silva, A. M. Ferrare, R. Randles, C. A. Govindaraju, R. Hair, J. Ziemba, L. D. |
author_facet |
Darmenov, A. Colarco, P. R. Buchard, V. Beyersdorf, A. J. Yu, H. da Silva, A. M. Ferrare, R. Randles, C. A. Govindaraju, R. Hair, J. Ziemba, L. D. |
author_sort |
Darmenov, A. |
title |
The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
title_short |
The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
title_full |
The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
title_fullStr |
The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
title_full_unstemmed |
The MERRA-2 Aerosol Reanalysis, 1980 Onward. Part II: Evaluation and Case Studies |
title_sort |
merra-2 aerosol reanalysis, 1980 onward. part ii: evaluation and case studies |
publishDate |
2017 |
url |
http://hdl.handle.net/2060/20190027472 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(12.615,12.615,65.816,65.816) |
geographic |
Merra |
geographic_facet |
Merra |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_source |
CASI |
op_relation |
Document ID: 20190027472 http://hdl.handle.net/2060/20190027472 |
op_rights |
Copyright, Public use permitted |
_version_ |
1766035230394679296 |