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| Titel |
Aerosol optical depth trend over the Middle East |
| VerfasserIn |
Klaus Klingmueller, Andrea Pozzer, Swen Metzger, Mohamed Abdelkader, Georgiy Stenchikov, Jos Lelieveld  |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250131707
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| Publikation (Nr.) |
 EGU/EGU2016-12142.pdf |
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| Zusammenfassung |
| We use the combined Dark Target/Deep Blue aerosol optical depth (AOD)
satellite product of the Moderate-resolution Imaging Spectroradiometer
(MODIS) collection 6 to study trends over the Middle East between 2000
and 2015. Our analysis corroborates a previously identified positive
AOD trend over large parts of the Middle East during the period 2001
to 2012.
By relating the annual AOD to precipitation, soil moisture and surface
wind, being the main factors controlling the dust cycle, we identify
regions where these attributes are significantly correlated to the AOD
over Saudi Arabia, Iraq and Iran. The Fertile Crescent turns out to be
of prime importance for the AOD trend over these countries.
Using multiple linear regression we show that AOD trend and
interannual variability can be attributed to the above mentioned dust
cycle parameters, confirming that the AOD increase is predominantly
driven by dust. In particular, the positive AOD trend relates to a
negative soil moisture trend. This suggests that increasing
temperature and decreasing relative humidity in the last decade have
promoted soil drying, leading to increased dust emissions and AOD;
consequently an AOD increase is expected due to climate change.
Based on simulations using the ECHAM/MESSy atmospheric
chemistry-climate model (EMAC), we interpret the correlations
identified in the observational data in terms of causal relationships. |
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