Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature
The Sahel rainfall has a close teleconnection with North Atlantic sea surface temperature (NASST) variability, which has separately been shown to be affected by aerosols. Therefore, changes in regional aerosols emission could potentially drive multidecadal Sahel rainfall variability. Here we combine...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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Wiley
2021
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| _version_ | 1797083090888163328 |
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| author | Zhang, S Stier, P Dagan, G Wang, M |
| author_facet | Zhang, S Stier, P Dagan, G Wang, M |
| author_sort | Zhang, S |
| collection | OXFORD |
| description | The Sahel rainfall has a close teleconnection with North Atlantic sea surface temperature (NASST) variability, which has separately been shown to be affected by aerosols. Therefore, changes in regional aerosols emission could potentially drive multidecadal Sahel rainfall variability. Here we combine ensembles of state-of-the-art global climate models (the CESM and CanESM large ensemble simulations and CMIP6 models) with observational data sets to demonstrate that anthropogenic aerosols have significantly impacted 20th-century detrended Sahel rainfall multidecadal variability through modifying NASST. We show that aerosol-induced multidecadal variations of downward solar radiative fluxes over the North Atlantic cause NASST variability during the 20th century, altering the ITCZ position and dynamically linking aerosol effects to Sahel rainfall variability. This process chain is caused by aerosol-induced changes in radiative surface fluxes rather than changes in ocean circulations. CMIP6 models further suggest that aerosol-cloud interactions modulate the inter-model uncertainty of simulated NASST and potentially the Sahel rainfall variability. |
| first_indexed | 2024-03-07T01:37:03Z |
| format | Journal article |
| id | oxford-uuid:958f567c-29c9-4798-9d2a-38e89c95e479 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T01:37:03Z |
| publishDate | 2021 |
| publisher | Wiley |
| record_format | dspace |
| spelling | oxford-uuid:958f567c-29c9-4798-9d2a-38e89c95e4792022-03-26T23:46:58ZAnthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperatureJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:958f567c-29c9-4798-9d2a-38e89c95e479EnglishSymplectic ElementsWiley2021Zhang, SStier, PDagan, GWang, MThe Sahel rainfall has a close teleconnection with North Atlantic sea surface temperature (NASST) variability, which has separately been shown to be affected by aerosols. Therefore, changes in regional aerosols emission could potentially drive multidecadal Sahel rainfall variability. Here we combine ensembles of state-of-the-art global climate models (the CESM and CanESM large ensemble simulations and CMIP6 models) with observational data sets to demonstrate that anthropogenic aerosols have significantly impacted 20th-century detrended Sahel rainfall multidecadal variability through modifying NASST. We show that aerosol-induced multidecadal variations of downward solar radiative fluxes over the North Atlantic cause NASST variability during the 20th century, altering the ITCZ position and dynamically linking aerosol effects to Sahel rainfall variability. This process chain is caused by aerosol-induced changes in radiative surface fluxes rather than changes in ocean circulations. CMIP6 models further suggest that aerosol-cloud interactions modulate the inter-model uncertainty of simulated NASST and potentially the Sahel rainfall variability. |
| spellingShingle | Zhang, S Stier, P Dagan, G Wang, M Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title | Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title_full | Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title_fullStr | Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title_full_unstemmed | Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title_short | Anthropogenic aerosols modulated 20th-century Sahel rainfall variability via their impacts on North Atlantic sea surface temperature |
| title_sort | anthropogenic aerosols modulated 20th century sahel rainfall variability via their impacts on north atlantic sea surface temperature |
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