Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps
This study explores the spatiotemporal variability of the onset, end, and duration of the rainy season in Senegal. These phenological parameters, crucial for agricultural planning in West Africa, exhibit high interannual and spatial variability linked to precipitation. The objective is to detect and...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-03-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/15/3/378 |
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| author | Dioumacor Faye François Kaly Abdou Lahat Dieng Dahirou Wane Cheikh Modou Noreyni Fall Juliette Mignot Amadou Thierno Gaye |
| author_facet | Dioumacor Faye François Kaly Abdou Lahat Dieng Dahirou Wane Cheikh Modou Noreyni Fall Juliette Mignot Amadou Thierno Gaye |
| author_sort | Dioumacor Faye |
| collection | DOAJ |
| description | This study explores the spatiotemporal variability of the onset, end, and duration of the rainy season in Senegal. These phenological parameters, crucial for agricultural planning in West Africa, exhibit high interannual and spatial variability linked to precipitation. The objective is to detect and spatially classify these indices across Senegal using different approaches. Daily precipitation data and ERA5 reanalyses from 1981 to 2018 were utilized. The employed method enables the detection of key dates. Subsequently, the Kohonen algorithm spatially classifies these indices on topological maps. The results indicate a meridional gradient of the onset, progressively later from the southeast to the northwest, whereas the end follows a north–south gradient. The duration varies from 45 days in the north to 150 days in the south. The use of self-organizing maps allows for classifying the onset, end, and duration of the season into four zones for the onset and end, and three zones for the duration of the season. They highlight the interannual irregularity of transitions, with both early and late years. The dynamic analysis underscores the complex influence of atmospheric circulation fields, notably emphasizing the importance of low-level monsoon flux. These findings have tangible implications for improving seasonal forecasts and agricultural activity planning in Senegal. They provide information on the onset, end, and duration classes for each specific zone, which can be valuable for planning crops adapted to each region. |
| first_indexed | 2024-04-24T18:33:39Z |
| format | Article |
| id | doaj.art-afaf07579af74b509b066385de19cb5c |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-04-24T18:33:39Z |
| publishDate | 2024-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-afaf07579af74b509b066385de19cb5c2024-03-27T13:20:51ZengMDPI AGAtmosphere2073-44332024-03-0115337810.3390/atmos15030378Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing MapsDioumacor Faye0François Kaly1Abdou Lahat Dieng2Dahirou Wane3Cheikh Modou Noreyni Fall4Juliette Mignot5Amadou Thierno Gaye6Laboratoire de Physique de l’Atmosphère et de l’Océan-Siméon Fongang (LPAO-SF), École Supérieure Polytechnique, Université Cheikh Anta Diop, Dakar 10700, SenegalDepartment of Computer Science, UFR of Sciences and Technologies, Université Iba Der THIAM de Thiès, Thies 21000, SenegalLaboratoire de Physique de l’Atmosphère et de l’Océan-Siméon Fongang (LPAO-SF), École Supérieure Polytechnique, Université Cheikh Anta Diop, Dakar 10700, SenegalLaboratoire de Physique de l’Atmosphère et de l’Océan-Siméon Fongang (LPAO-SF), École Supérieure Polytechnique, Université Cheikh Anta Diop, Dakar 10700, SenegalLaboratoire de Physique de l’Atmosphère et de l’Océan-Siméon Fongang (LPAO-SF), École Supérieure Polytechnique, Université Cheikh Anta Diop, Dakar 10700, SenegalLaboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques, Institut Pierre Simon Laplace, SU/IRD/CNRS/MNHN, UMR 7159, 75005 Paris, FranceLaboratoire de Physique de l’Atmosphère et de l’Océan-Siméon Fongang (LPAO-SF), École Supérieure Polytechnique, Université Cheikh Anta Diop, Dakar 10700, SenegalThis study explores the spatiotemporal variability of the onset, end, and duration of the rainy season in Senegal. These phenological parameters, crucial for agricultural planning in West Africa, exhibit high interannual and spatial variability linked to precipitation. The objective is to detect and spatially classify these indices across Senegal using different approaches. Daily precipitation data and ERA5 reanalyses from 1981 to 2018 were utilized. The employed method enables the detection of key dates. Subsequently, the Kohonen algorithm spatially classifies these indices on topological maps. The results indicate a meridional gradient of the onset, progressively later from the southeast to the northwest, whereas the end follows a north–south gradient. The duration varies from 45 days in the north to 150 days in the south. The use of self-organizing maps allows for classifying the onset, end, and duration of the season into four zones for the onset and end, and three zones for the duration of the season. They highlight the interannual irregularity of transitions, with both early and late years. The dynamic analysis underscores the complex influence of atmospheric circulation fields, notably emphasizing the importance of low-level monsoon flux. These findings have tangible implications for improving seasonal forecasts and agricultural activity planning in Senegal. They provide information on the onset, end, and duration classes for each specific zone, which can be valuable for planning crops adapted to each region.https://www.mdpi.com/2073-4433/15/3/378regionalizationonsetoffsetself-organizing mapsrainy seasonSenegal |
| spellingShingle | Dioumacor Faye François Kaly Abdou Lahat Dieng Dahirou Wane Cheikh Modou Noreyni Fall Juliette Mignot Amadou Thierno Gaye Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps Atmosphere regionalization onset offset self-organizing maps rainy season Senegal |
| title | Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps |
| title_full | Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps |
| title_fullStr | Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps |
| title_full_unstemmed | Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps |
| title_short | Regionalization of the Onset and Offset of the Rainy Season in Senegal Using Kohonen Self-Organizing Maps |
| title_sort | regionalization of the onset and offset of the rainy season in senegal using kohonen self organizing maps |
| topic | regionalization onset offset self-organizing maps rainy season Senegal |
| url | https://www.mdpi.com/2073-4433/15/3/378 |
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