Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves
The present study utilizes three high-resolution simulations from the Regional Climate Model version 4 (RegCM4) to examine the late 21st century changes (2080–2099) in the West African Monsoon (WAM) features. A set of three Earth System Models are utilized to provide initial and lateral boundary con...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-04-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/11/4/353 |
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| author | Ibourahima Kebe Ismaila Diallo Mouhamadou Bamba Sylla Fernando De Sales Arona Diedhiou |
| author_facet | Ibourahima Kebe Ismaila Diallo Mouhamadou Bamba Sylla Fernando De Sales Arona Diedhiou |
| author_sort | Ibourahima Kebe |
| collection | DOAJ |
| description | The present study utilizes three high-resolution simulations from the Regional Climate Model version 4 (RegCM4) to examine the late 21st century changes (2080–2099) in the West African Monsoon (WAM) features. A set of three Earth System Models are utilized to provide initial and lateral boundary conditions to the RegCM4 experiments. Our analysis focuses on seasonal mean changes in WAM large-scale dynamical features, along with their connections with the summer monsoon precipitation. In the historical period, the simulation ensemble means mimic reasonably well the intensity and spatial distribution of the WAM rainfall as well as the WAM circulation patterns at different scales. The future projection of the WAM climate exhibits warming over the whole West Africa leading to precipitation reduction over the Sahel region, and a slight increase over some areas of the Guinea Coast. The position of the African Easterly Jet (AEJ) is shifted southward and the African Easterly Waves (AEWs) activities are reduced, which affect in turn the WAM rainbelt characteristics in terms of position and strength. Overall the changes in simulated AEJ and AEWs contribute substantially to reduce the seasonal summer mean precipitation in West Africa by the late 21st century, with prevailing negative changes in the Savanna-Sahel region. To further explore the robustness of the relationships revealed in this paper, future studies using different high-resolution regional climate models with large ensemble are recommended. |
| first_indexed | 2024-03-10T20:40:11Z |
| format | Article |
| id | doaj.art-854cba2c34654e67918ccaac10341190 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-03-10T20:40:11Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-854cba2c34654e67918ccaac103411902023-11-19T20:43:38ZengMDPI AGAtmosphere2073-44332020-04-0111435310.3390/atmos11040353Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly WavesIbourahima Kebe0Ismaila Diallo1Mouhamadou Bamba Sylla2Fernando De Sales3Arona Diedhiou4West African Science Service Center on Climate Change and Adapted Landuse (WASCAL) Graduate Research Program on West African Climate System, Federal University of Technology, P.M.B. 704 Akure, NigeriaDepartment of Geography, University of California—Los Angeles, Los Angeles, CA 90095, USAAfrican Institute for Mathematical Sciences (AIMS), AIMS Rwanda Center, KN 3, P.O. Box 71 50 Kigali, RwandaDepartment of Geography, San Diego State University, San Diego, CA 92182, USAInstitute of Research for Development IRD, CNRS, Grenoble INP, IGE, University Grenoble Alpes, F-38000 Grenoble, FranceThe present study utilizes three high-resolution simulations from the Regional Climate Model version 4 (RegCM4) to examine the late 21st century changes (2080–2099) in the West African Monsoon (WAM) features. A set of three Earth System Models are utilized to provide initial and lateral boundary conditions to the RegCM4 experiments. Our analysis focuses on seasonal mean changes in WAM large-scale dynamical features, along with their connections with the summer monsoon precipitation. In the historical period, the simulation ensemble means mimic reasonably well the intensity and spatial distribution of the WAM rainfall as well as the WAM circulation patterns at different scales. The future projection of the WAM climate exhibits warming over the whole West Africa leading to precipitation reduction over the Sahel region, and a slight increase over some areas of the Guinea Coast. The position of the African Easterly Jet (AEJ) is shifted southward and the African Easterly Waves (AEWs) activities are reduced, which affect in turn the WAM rainbelt characteristics in terms of position and strength. Overall the changes in simulated AEJ and AEWs contribute substantially to reduce the seasonal summer mean precipitation in West Africa by the late 21st century, with prevailing negative changes in the Savanna-Sahel region. To further explore the robustness of the relationships revealed in this paper, future studies using different high-resolution regional climate models with large ensemble are recommended.https://www.mdpi.com/2073-4433/11/4/353RegCM4climate changeWest African MonsoonAfrican Easterly JetAfrican Easterly Waveshigh-resolution regional climate models |
| spellingShingle | Ibourahima Kebe Ismaila Diallo Mouhamadou Bamba Sylla Fernando De Sales Arona Diedhiou Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves Atmosphere RegCM4 climate change West African Monsoon African Easterly Jet African Easterly Waves high-resolution regional climate models |
| title | Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves |
| title_full | Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves |
| title_fullStr | Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves |
| title_full_unstemmed | Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves |
| title_short | Late 21st Century Projected Changes in the Relationship between Precipitation, African Easterly Jet, and African Easterly Waves |
| title_sort | late 21st century projected changes in the relationship between precipitation african easterly jet and african easterly waves |
| topic | RegCM4 climate change West African Monsoon African Easterly Jet African Easterly Waves high-resolution regional climate models |
| url | https://www.mdpi.com/2073-4433/11/4/353 |
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