Understanding hydroclimatic variability in the Sahel and Sudanian zones is critical for improving climate resilience and resource management. This study presents a comparative analysis of drought dynamics in two representative agroecological sites of Mali Cinzana (Sahelian zone) and Kola (Sudanian zone) over the period 1994-2022. Using meteorological data, drought characteristics were assessed through the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI), complemented by trend detection methods (Mann-Kendall, Sen’s slope) and the Pettitt test for structural breaks. Results reveal marked local divergences despite the geographical proximity of the sites. At Cinzana, rainfall and temperature trends were not statistically significant, although a positive and significant trend in SPEI-12 suggests a tendency toward wetter annual conditions consistent with the Sahelian “regreening” observed since the 1990s. In contrast, Kola exhibited a statistically significant warming, particularly in minimum temperature (+0.057？C/year, p < 0.001), with a breakpoint in 2008 indicating accelerated nighttime warming. Drought indices at Kola revealed significant negative trends in SPI-12, SPEI-6, and SPEI-9, highlighting an intensification of aridification processes. Correlation analysis between SPI and SPEI confirmed that rainfall remains the dominant driver of drought variability at multi-annual scales, while evapotranspiration, amplified by warming, plays an increasingly critical role at seasonal scales. Overall, these findings demonstrate the coexistence of greening and drying trajectories within short geographic distances, reflecting the high spatial heterogeneity of Sahelian climate dynamics. This heterogeneity underscores the need for fine-scale analyses to refine regional climate projections and to design differentiated adaptation strategies for water resource management and agricultural production.
References
[1]
Abramowitz, M., & Stegun, I. A. (1965). Handbook of Mathematical Functions: With Formulas, Graphs, and Mathematical Tables (vol. 55). Courier Corporation. https://books.google.com/books?hl=fr&lr=&id=MtU8uP7XMvoC&oi=fnd&pg=PR9&dq=Abramowitz+%26+Stegun,+1965+&ots=-HTNSmP5Gj&sig=gHvuQgljQaftR3bybIvv_Wk_Iew
[2]
Ali, A., Amani, A., Diedhiou, A., & Lebel, T. (2005). Rainfall Estimation in the Sahel. Part II: Evaluation of Rain Gauge Networks in the CILSS Countries and Objective Intercomparison of Rainfall Products. JournalofAppliedMeteorology,44, 1707-1722. https://doi.org/10.1175/jam2305.1
[3]
Ayugi, B., Eresanya, E. O., Onyango, A. O., Ogou, F. K., Okoro, E. C., Okoye, C. O. et al. (2022). Review of Meteorological Drought in Africa: Historical Trends, Impacts, Mitigation Measures, and Prospects. PureandAppliedGeophysics,179, 1365-1386. https://doi.org/10.1007/s00024-022-02988-z
[4]
Biasutti, M. (2013). Forced Sahel Rainfall Trends in the CMIP5 Archive. JournalofGeophysicalResearch:Atmospheres,118, 1613-1623. https://doi.org/10.1002/jgrd.50206
[5]
Bodian, A., Diop, L., Panthou, G., Dacosta, H., Deme, A., Dezetter, A. et al. (2020). Recent Trend in Hydroclimatic Conditions in the Senegal River Basin. Water,12, Article 436. https://doi.org/10.3390/w12020436
[6]
Cerpa Reyes, L. J., Ávila Rangel, H., & Herazo, L. C. S. (2022). Adjustment of the Standardized Precipitation Index (SPI) for the Evaluation of Drought in the Arroyo Pechelín Basin, Colombia, under Zero Monthly Precipitation Conditions. Atmosphere,13, Article 236. https://doi.org/10.3390/atmos13020236
[7]
Chukwuma Sr, D. C. (2025). Invariance of Extreme Hydrologic Events and Climate Change in the Risk Reduction on Environment and Health. GreenfortInternationalJournalofAppliedMedicalScience,3, 92-102. https://doi.org/10.62046/gijams.2025.v03i02.011
[8]
Daku, E. K., Salack, S., Worou, O. N., & Ogunjobi, K. (2022). Maize Response to Temporary Floods under Ambient On-Farm Conditions of the West African Sahel. EnvironmentalResearchCommunications,4, Article ID: 045004. https://doi.org/10.1088/2515-7620/ac6073
[9]
Descroix, L., Guichard, F., Grippa, M., Lambert, L. A., Panthou, G., Mahé, G. et al. (2018). Evolution of Surface Hydrology in the Sahelo-Sudanian Strip: An Updated Review. Water,10, Article 748. https://doi.org/10.3390/w10060748
[10]
Edwards, D. C. (1997). Characteristics of 20th Century Drought in the United States at Multiple Time Scales. https://apps.dtic.mil/sti/html/tr/ADA325595/
[11]
Faye, C. (2022). Comparative Analysis of Meteorological Drought Based on the SPI and SPEI Indices. HighTechandInnovationJournal,3, 15-27. https://doi.org/10.28991/hij-sp2022-03-02
[12]
Faye, M. (2023). Evolution de la fréquence des flux d’harmattan et hausse de la température à l’extréme nord du Sénégal de 1991 à 2020: La station de Saint-Louis et de Podor. https://rivieresdusud.uasz.sn/handle/123456789/2081
[13]
Gaye, D., & Sow, S. A. (2019). Variabilité pluviométrique au Sahel sénégalais: Évaluation du retour progressif vers la normale. Revue Ivoirienne des Sciences et Technologie, 33, 84-105. https://revist.net/REVIST_33/REVIST_33_6.pdf
[14]
Govoeyi, B., Tignégré, J. D. L. S., Badolo, F., Zaato, P. A., Sanogo, K., & Birhanu, B. Z. (2022). Perceptions on Sack Gardening in Rural Areas: The Case of Vegetable Stakeholders in Koutiala and Bougouni, Mali. Sustainability,14, Article 14896. https://doi.org/10.3390/su142214896
[15]
Gupta, S. (2022). ClimateMigrationtotheGlobalGateway. https://dspace.cuni.cz/handle/20.500.11956/177428
[16]
Haile, B. T., Bekitie, K. T., Zeleke, T. T., Ayal, D. Y., Feyisa, G. L., & Anose, F. A. (2022). Drought Analysis Using Standardized Evapotranspiration and Aridity Index at Bilate Watershed: Sub-Basins of Ethiopian Rift Valley. TheScientificWorldJournal,2022, Article ID: 1181198. https://doi.org/10.1155/2022/1181198
[17]
Halimatou, T., Nouhoun, Z., Kalifa, T., & Nicholas, K. (2016). Farmers’ Perceptions on Climate Variability and Adaptation Strategies to Climate Change in Cinzana, Mali. JournalofAgriculturalStudies,4, 13-36. https://doi.org/10.5296/jas.v4i3.9331
[18]
Hargreaves, G. H., & Samani, Z. A. (1985). Reference Crop Evapotranspiration from Temperature. AppliedEngineeringinAgriculture,1, 96-99. https://doi.org/10.13031/2013.26773
[19]
Haslinger, K., Koffler, D., Schöner, W., & Laaha, G. (2014). Exploring the Link between Meteorological Drought and Streamflow: Effects of Climate‐catchment Interaction. WaterResourcesResearch,50, 2468-2487. https://doi.org/10.1002/2013wr015051
[20]
Holleman, C., Rembold, F., Crespo, O., & Conti, V. (2020). The Impact of Climate Variabilityand Extremes on Agriculture and Food Security: An Analysis ofthe Evidenceand Case Studies. https://ageconsearch.umn.edu/record/309365/
[21]
Kumar, R., Kumar, A., & Saikia, P. (2022). Deforestation and Forests Degradation Impacts on the Environment. In V. P. Singh, S. Yadav, K. K. Yadav, & R. N. Yadava (Eds.), Environmental Degradation: Challenges and Strategies for Mitigation (pp. 19-46). Springer International Publishing. https://doi.org/10.1007/978-3-030-95542-7_2
[22]
Labudová, L., Labuda, M., & Takáč, J. (2017). Comparison of SPI and SPEI Applicability for Drought Impact Assessment on Crop Production in the Danubian Lowland and the East Slovakian Lowland. TheoreticalandAppliedClimatology,128, 491-506. https://doi.org/10.1007/s00704-016-1870-2
[23]
Lebel, T., Panthou, G., & Vischel, T. (2018). Au Sahel, pas de retour à la normale après la «grande sécheresse». https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-01/010079165.pdf
[24]
Legg, S. (2021). IPCC, 2021: Climate Change 2021: the Physical Science Basis. Interaction, 49, 44-45. https://search.informit.org/doi/abs/10.3316/informit.315096509383738
[25]
Li, Y., Liu, W., Feng, Q., Zhu, M., Yang, L., & Zhang, J. (2022). Quantitative Assessment for the Spatiotemporal Changes of Ecosystem Services, Tradeoff-Synergy Relationships and Drivers in the Semi-Arid Regions of China. RemoteSensing,14, Article 239. https://doi.org/10.3390/rs14010239
[26]
Mann, H. B. (1945). Nonparametric Tests against Trend. Econometrica,13, 245-259. https://doi.org/10.2307/1907187
[27]
Mganga, K. Z. (2022). Agricultural Land Degradation in Kenya. In P. Pereira, M. Muñoz-Rojas, I. Bogunovic, & W. Zhao (Eds.), Impact of Agriculture on Soil Degradation I (pp. 273-300). Springer International Publishing. https://doi.org/10.1007/698_2022_929
[28]
Mohammed, S., Alsafadi, K., Enaruvbe, G. O., Bashir, B., Elbeltagi, A., Széles, A. et al. (2022). Assessing the Impacts of Agricultural Drought (SPI/SPEI) on Maize and Wheat Yields across Hungary. ScientificReports,12, Article No. 8838. https://doi.org/10.1038/s41598-022-12799-w
[29]
Monerie, P., Pohl, B., & Gaetani, M. (2021). The Fast Response of Sahel Precipitation to Climate Change Allows Effective Mitigation Action. npjClimateandAtmosphericScience,4, Article No. 24. https://doi.org/10.1038/s41612-021-00179-6
[30]
Morsy, M., Moursy, F. I., Sayad, T., & Shaban, S. (2022). Climatological Study of SPEI Drought Index Using Observed and CRU Gridded Dataset over Ethiopia. PureandAppliedGeophysics,179, 3055-3073. https://doi.org/10.1007/s00024-022-03091-z
[31]
Nguru, W., & Mwongera, C. (2022). Évaluation de la vulnérabilité climatique de certaines cultures au Sénégal. https://cgspace.cgiar.org/items/925001cf-c6ec-4319-b4eb-57f5b337b892
[32]
Noguera, I., Vicente-Serrano, S. M., Domínguez-Castro, F., & Reig, F. (2022). Assessment of Parametric Approaches to Calculate the Evaporative Demand Drought Index. InternationalJournalofClimatology,42, 834-849. https://doi.org/10.1002/joc.7275
[33]
Nouaceur, Z. (2020). La reprise des pluies et la recrudescence des inondations en Afrique de l’Ouest sahélienne. Physio-Géo, 15, 89-109. https://doi.org/10.4000/physio-geo.10966
[34]
Orlandi, M. (2023). The Relationship between Natural Resourcesand Conflicts inAfrica-DeconstructingMalthusthroughthePoliticalEcology Approach. https://unitesi.unive.it/handle/20.500.14247/14085
[35]
Padgham, J., Abubakari, A., Ayivor, J., Dietrich, K., Fosu-Mensah, B., Gordon, C., Hab-tezion, S., Lawson, E., Mensah, A., & Nukpezah, D. (2015). Vulnerabilityand Adaptation to Climate Change inthe Semi-Arid Regions ofWestAfrica. https://idl-bnc-idrc.dspacedirect.org/bitstream/handle/10625/58627/IDL-58627.pdf
[36]
Panigrahi, S., & Vidyarthi, V. K. (2024). Assessing the Suitability of Mckee et al. (1993) Drought Severity Classification across India. NaturalHazards,120, 13543-13572. https://doi.org/10.1007/s11069-024-06762-3
[37]
Pettitt, A. N. (1979). A Non-Parametric Approach to the Change-Point Problem. AppliedStatistics,28, 126-135. https://doi.org/10.2307/2346729
[38]
Rockström, J., Steffen, W., Noone, K., Persson, Å., Chapin, F. S. I., Lambin, E. et al. (2009). Planetary Boundaries: Exploring the Safe Operating Space for Humanity. EcologyandSociety,14, Article 32. https://doi.org/10.5751/es-03180-140232
[39]
Sanogo, S. (2022). Observations et modélisation des extrêmes de précipitation aux échelles saisonnière à interannuelle au Sahel. Master’s Thesis, Institut National Polytechnique de Tou-louse-INPT. https://hal.science/tel-04124637/
[40]
Sarr, B., Atta, S., Ly, M., Salack, S., Ourback, T., Subsol, S., & George, D. A. (2015). Adapting to Climate Variability and Change in Smallholder Farming Communities: A Case Study from Burkina Faso, Chad and Niger. JournalofAgriculturalExtensionandRuralDevelopment,7, 16-27. https://doi.org/10.5897/jaerd14.0595
[41]
Sarra, M., Traore, S., Sarr, T., & Soumare, M. (2022). Manifestations de la variabilité et du changement climatique perçues par les producteurs de basfond dans la commune rurale de Doumanaba au Mali. African Scientific Journal,3, 141-159. https://www.academia.edu/download/123571361/N12-8-Manifesta-tions_20of_20climate_20variability_20and_20change_20perceived_20by_20lowland_20producers_20in_20the_20rural_20commune_20o.pdf
[42]
Sen, P. K. (1968). Estimates of the Regression Coefficient Based on Kendall’s Tau. JournaloftheAmericanStatisticalAssociation,63, 1379-1389. https://doi.org/10.1080/01621459.1968.10480934
[43]
Siddha, S., & Sahu, P. (2022). Impact of Climate Change on the River Ecosystem. In S. Madhav, et al. (Eds.), EcologicalSignificanceofRiverEcosystems (pp. 79-104). Elsevier. https://doi.org/10.1016/b978-0-323-85045-2.00014-5
[44]
Smart, C. (2017). Rainfall Variability and Drought inthe Central and Northern KwaZulu-NatalDrakensberg:1955-2015. https://search.proquest.com/openview/bc39438d04fd639550669445fc69a884/1?pq-origsite=gscholar&cbl=2026366&diss=y
[45]
Sylla, M. B., Nikiema, P. M., Gibba, P., Kebe, I., & Klutse, N. A. B. (2016). Climate Change over West Africa: Recent Trends and Future Projections. In J. Yaro, & J. Hesselberg (Eds.), AdaptationtoClimateChangeandVariabilityinRuralWestAfrica (pp. 25-40). Springer International Publishing. https://doi.org/10.1007/978-3-319-31499-0_3
[46]
Tall, M., Sylla, M. B., Dajuma, A., & Koubodana Houteta, D. (2022). Drought Hotspots and Recent Changesin Their Characteristics acrosstheAfrican Continent duringthe Historical Period (1928-2017). https://ui.adsabs.harvard.edu/abs/2022AGUFMGC55G0313T/abstract
[47]
Tefera, A. S., Ayoade, J. O., & Bello, N. J. (2019). Comparative Analyses of SPI and SPEI as Drought Assessment Tools in Tigray Region, Northern Ethiopia. SNAppliedSciences,1, Article No. 1265. https://doi.org/10.1007/s42452-019-1326-2
[48]
Traore, L., Bello, O. D., Balogoun, B., Chabi, F., Issifou, M. Y., Yabi, Y. et al. (2022). Variabilité Intra-saisonnière des Pluies et Production du Sorgho en Zones Soudanienne et Sahélienne du Mali. European Scientific Journal ESJ, 9, 44-68. https://doi.org/10.19044/esipreprint.9.2022.p44
[49]
Zerbe, S. (2022). Global Land-Use Development Trends: Traditional Cultural Landscapes under Threat. In S. Zerbe (Ed.), Restoration of Multifunctional Cultural Landscapes (pp. 129-199). Springer International Publishing. https://doi.org/10.1007/978-3-030-95572-4_4
[50]
Zhou, Y., Li, Y., Li, W., Li, F., & Xin, Q. (2022). Ecological Responses to Climate Change and Human Activities in the Arid and Semi-Arid Regions of Xinjiang in China. RemoteSensing,14, Article 3911. https://doi.org/10.3390/rs14163911
[51]
Zittis, G., Almazroui, M., Alpert, P., Ciais, P., Cramer, W., Dahdal, Y. et al. (2022). Climate Change and Weather Extremes in the Eastern Mediterranean and Middle East. ReviewsofGeophysics,60, e2021RG000762. https://doi.org/10.1029/2021rg000762
