Global dust optical depth climatology derived from CALIOP and MODIS aerosol retrievals on decadal timescales: regional and interannual variability

Simple item page
dc.contributor.authorSong, Qianqian
dc.contributor.authorZhang, Zhibo
dc.contributor.authorYu, Hongbin
dc.contributor.authorGinoux, Paul
dc.contributor.authorShen, Jerry
dc.date.accessioned2022-05-03T14:19:15Z
dc.date.available2022-05-03T14:19:15Z
dc.date.issued2021-09-09
dc.description.abstractWe derived two observation-based global monthly mean dust aerosol optical depth (DAOD) climatological datasets from 2007 to 2019 with a 2° (latitude) × 5° (longitude) spatial resolution, one based on Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and the other on Moderate Resolution Imaging Spectroradiometer (MODIS) observations. In addition, the CALIOP climatological dataset also includes dust vertical extinction profiles. Dust is distinguished from non-dust aerosols based on particle shape information (e.g., lidar depolarization ratio) for CALIOP and on dust size and absorption information (e.g., fine-mode fraction, Ångström exponent, and single-scattering albedo) for MODIS, respectively. The two datasets compare reasonably well with the results reported in previous studies and the collocated Aerosol Robotic Network (AERONET) coarse-mode AOD. Based on these two datasets, we carried out a comprehensive comparative study of the spatial and temporal climatology of dust. On a multi-year average basis, the global (60° S–60° N) annual mean DAOD is 0.032 and 0.067 according to CALIOP and MODIS retrievals, respectively. In most dust-active regions, CALIOP DAOD generally correlates well (correlation coefficient R > 0.6) with the MODIS DAOD, although the CALIOP value is significantly smaller. The CALIOP DAOD is 18 %, 34 %, 54 %, and 31 % smaller than MODIS DAOD over the Sahara, the tropical Atlantic Ocean, the Caribbean Sea, and the Arabian Sea, respectively. Applying a regional specific lidar ratio (LR) of 58 sr instead of the 44 sr used in the CALIOP operational retrieval reduces the difference from 18 % to 8 % over the Sahara and from 34 % to 12 % over the tropical Atlantic Ocean. However, over eastern Asia and the northwestern Pacific Ocean (NWP), the two datasets show weak correlation. Despite these discrepancies, CALIOP and MODIS show similar seasonal and interannual variations in regional DAOD. For dust aerosol over the NWP, both CALIOP and MODIS show a declining trend of DAOD at a rate of about 2 % yr⁻¹ . This decreasing trend is consistent with the observed declining trend of DAOD in the southern Gobi Desert at a rate of 3 % yr⁻¹ and 5 % yr⁻¹ according to CALIOP and MODIS, respectively. The decreasing trend of DAOD in the southern Gobi Desert is in turn found to be significantly correlated with increasing vegetation and decreasing surface wind speed in the area.en_US
dc.description.sponsorshipQianqian Song and Zhibo Zhang cordially acknowledge the funding support from the Future Investigators in NASA Earth and Space Science and Technology (FINESST). Zhibo Zhang’s research is supported by a NASA grant (no. 80NSSC20K0130) from the CALIPSO and CloudSat program managed by David Considine. Hongbin Yu was supported by NASA’s the Science of Terra, Aqua, and Suomi-NPP and the CALIPSO/CloudSat Science Team programs administered by Hal Maring and David Considine, respectively. The computations in this study were performed at the UMBC High Performance Computing Facility (HPCF). The facility is supported by the US National Science Foundation through the MRI program (grant nos. CNS0821258 and CNS-1228778) and the SCREMS program (grant no. DMS-0821311), with substantial support from UMBC. The MODIS aerosol data were obtained from the NASA Level-1 and Atmosphere Archive and Distribution System (LAADS) web page (https://ladsweb.nascom.nasa.gov/, last access: 9 February 2021). The CALIOP aerosol products were obtained from NASA Langley Research Center Atmospheric Science Data Center (https: //eosweb.larc.nasa.gov/, last access: 9 February 2019). Financial support. This research has been supported by the National Aeronautics and Space Administration (grant nos. 80NSSC20K0130, 80NSSC19K1345, CNS-0821258, CNS1228778, and DMS-0821311). Review statement. This paper was edited by Xiaohong Liu and reviewed by three anonymous referees.en_US
dc.description.urihttps://acp.copernicus.org/articles/21/13369/2021/acp-21-13369-2021-discussion.htmlen_US
dc.format.extent27 pagesen_US
dc.genrejournal articlesen_US
dc.identifierdoi:10.13016/m2wbx7-0orw
dc.identifier.citationSong, Qianqian et al. Global dust optical depth climatology derived from CALIOP and MODIS aerosol retrievals on decadal timescales: regional and interannual variability. Atmospheric Chemistry and Physics 21, (Sept 9, 2021) no 17, 13369–13395. https://doi.org/10.5194/acp-21-13369-2021en_US
dc.identifier.urihttps://doi.org/10.5194/acp-21-13369-2021
dc.identifier.urihttp://hdl.handle.net/11603/24666
dc.language.isoen_USen_US
dc.publisherEGUen_US
dc.relation.isAvailableAtThe University of Maryland, Baltimore County (UMBC)
dc.relation.ispartofUMBC Joint Center for Earth Systems Technology
dc.relation.ispartofUMBC Faculty Collection
dc.relation.ispartofUMBC Student Collection
dc.relation.ispartofUMBC Physics Department
dc.rightsThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.en_US
dc.rightsAttribution 4.0 International (CC BY 4.0)*
dc.rights.urihttps://creativecommons.org/licenses/by/4.0/*
dc.subjectUMBC High Performance Computing Facility (HPCF)
dc.titleGlobal dust optical depth climatology derived from CALIOP and MODIS aerosol retrievals on decadal timescales: regional and interannual variabilityen_US
dc.typeTexten_US
dcterms.creatorhttps://orcid.org/0000-0001-9491-1654en_US
dcterms.creatorhttps://orcid.org/0000-0003-4706-1575en_US

Files

Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
acp-21-13369-2021.pdf
Size:
10.7 MB
Format:
Adobe Portable Document Format
Description:
Download
Thumbnail Image
Name:
acp-21-13369-2021-supplement.pdf
Size:
1.5 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
2.56 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

UMBC Joint Center for Earth Systems Technology (JCET)
UMBC Faculty Collection
UMBC Physics Department
UMBC Student Collection