Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0
© 2014. American Geophysical Union. All rights reserved. This study uses a century length preindustrial climate simulation by the Community Earth System Model (CESM 1.0) to explore statistical relationships between dust, clouds, and atmospheric circulation and to suggest a semidirect dynamical mecha...
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ftcdlib:qt0fh3k2n4 2023-05-15T17:28:35+02:00 Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 Deflorio, MJ Ghan, SJ Singh, B Miller, AJ Cayan, DR Russell, LM Somerville, RCJ 8284 - 8303 2014-07-16 application/pdf http://www.escholarship.org/uc/item/0fh3k2n4 english eng eScholarship, University of California qt0fh3k2n4 http://www.escholarship.org/uc/item/0fh3k2n4 public Deflorio, MJ; Ghan, SJ; Singh, B; Miller, AJ; Cayan, DR; Russell, LM; et al.(2014). Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0. Journal of Geophysical Research, 119(13), 8284 - 8303. doi:10.1002/2013JD020997. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/0fh3k2n4 article 2014 ftcdlib https://doi.org/10.1002/2013JD020997 2018-07-13T22:54:35Z © 2014. American Geophysical Union. All rights reserved. This study uses a century length preindustrial climate simulation by the Community Earth System Model (CESM 1.0) to explore statistical relationships between dust, clouds, and atmospheric circulation and to suggest a semidirect dynamical mechanism linking subtropical North Atlantic lower tropospheric cloud cover with North African dust transport. The length of the run allows us to account for interannual variability of North African dust emissions and transport in the model. CESM’s monthly climatology of both aerosol optical depth and surface dust concentration at Cape Verde and Barbados, respectively, agree well with available observations, as does the aerosol size distribution at Cape Verde. In addition, CESM shows strong seasonal cycles of dust burden and lower tropospheric cloud fraction, with maximum values occurring during boreal summer, when a strong correlation between these two variables exists over the subtropical North Atlantic. Calculations of Estimated Inversion Strength (EIS) and composites of EIS on high and low downstream North African dust months during boreal summer reveal that dust is likely increasing inversion strength over this region due to both solar absorption and reflection. We find no evidence for a microphysical link between dust and lower tropospheric clouds in this region. These results yield new insight over an extensive period of time into the complex relationship between North African dust and North Atlantic lower tropospheric clouds, which has previously been hindered by spatiotemporal constraints of observations. Our findings lay a framework for future analyses using different climate models and submonthly data over regions with different underlying dynamics. Article in Journal/Newspaper North Atlantic University of California: eScholarship Journal of Geophysical Research: Atmospheres 119 13 8284 8303 |
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Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
description |
© 2014. American Geophysical Union. All rights reserved. This study uses a century length preindustrial climate simulation by the Community Earth System Model (CESM 1.0) to explore statistical relationships between dust, clouds, and atmospheric circulation and to suggest a semidirect dynamical mechanism linking subtropical North Atlantic lower tropospheric cloud cover with North African dust transport. The length of the run allows us to account for interannual variability of North African dust emissions and transport in the model. CESM’s monthly climatology of both aerosol optical depth and surface dust concentration at Cape Verde and Barbados, respectively, agree well with available observations, as does the aerosol size distribution at Cape Verde. In addition, CESM shows strong seasonal cycles of dust burden and lower tropospheric cloud fraction, with maximum values occurring during boreal summer, when a strong correlation between these two variables exists over the subtropical North Atlantic. Calculations of Estimated Inversion Strength (EIS) and composites of EIS on high and low downstream North African dust months during boreal summer reveal that dust is likely increasing inversion strength over this region due to both solar absorption and reflection. We find no evidence for a microphysical link between dust and lower tropospheric clouds in this region. These results yield new insight over an extensive period of time into the complex relationship between North African dust and North Atlantic lower tropospheric clouds, which has previously been hindered by spatiotemporal constraints of observations. Our findings lay a framework for future analyses using different climate models and submonthly data over regions with different underlying dynamics. |
format |
Article in Journal/Newspaper |
author |
Deflorio, MJ Ghan, SJ Singh, B Miller, AJ Cayan, DR Russell, LM Somerville, RCJ |
spellingShingle |
Deflorio, MJ Ghan, SJ Singh, B Miller, AJ Cayan, DR Russell, LM Somerville, RCJ Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
author_facet |
Deflorio, MJ Ghan, SJ Singh, B Miller, AJ Cayan, DR Russell, LM Somerville, RCJ |
author_sort |
Deflorio, MJ |
title |
Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
title_short |
Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
title_full |
Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
title_fullStr |
Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
title_full_unstemmed |
Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0 |
title_sort |
semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in cesm 1.0 |
publisher |
eScholarship, University of California |
publishDate |
2014 |
url |
http://www.escholarship.org/uc/item/0fh3k2n4 |
op_coverage |
8284 - 8303 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Deflorio, MJ; Ghan, SJ; Singh, B; Miller, AJ; Cayan, DR; Russell, LM; et al.(2014). Semidirect dynamical and radiative effect of north african dust transport on lower tropospheric clouds over the subtropical north atlantic in CESM 1.0. Journal of Geophysical Research, 119(13), 8284 - 8303. doi:10.1002/2013JD020997. UC San Diego: Retrieved from: http://www.escholarship.org/uc/item/0fh3k2n4 |
op_relation |
qt0fh3k2n4 http://www.escholarship.org/uc/item/0fh3k2n4 |
op_rights |
public |
op_doi |
https://doi.org/10.1002/2013JD020997 |
container_title |
Journal of Geophysical Research: Atmospheres |
container_volume |
119 |
container_issue |
13 |
container_start_page |
8284 |
op_container_end_page |
8303 |
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1766121346406809600 |