Simulation of future climate scenarios for Niger’s Dosso region

Abstract

Climate change presents a critical global challenge, particularly impacting the sustainability and resilience of ecosystems and human societies, with a heightened effect in sub-Saharan Africa. The Dosso region of Niger, home to over 3 million people, faces the highest multi-hazard risk in West Africa due to recurrent extreme weather and climate events. However, there is a lack of information on future climate hazards in Dosso. This study utilizes the ensemble mean of five CMIP6-based GCMs and sixteen core indices from the WMO ET-SCI to analyze the projected temperature and precipitation patterns and their extremes in Dosso for the future period (2025 2060) with reference period (1979-2014), under low-emission scenarios (SSP1 RCP 2.6) and high emission scenarios (SSP3 RCP 7.0). The study's results indicate a slight average increase of 65 mm/year in annual rainfall with no significant trend under SSP126 scenarios and a more pronounced increase of 150 mm/year under SSP370 scenarios. The GCM ensemble mean projects an average annual temperature rise of 1ºC under SSP126 scenarios and 1.5ºC under SSP370 scenarios for the future period. Extreme precipitation-based indices exhibit no significant trend under SSP1-RCP26 scenarios, while significant positive trends are observed under SSP3-RCP70 scenarios, except for consecutive wet days and consecutive dry days which show slightly decreasing and increasing insignificant trends, respectively. Conversely, under both SSP1-RCP2.6 and SSP3-RCP7.0 scenarios, all extreme temperature-based indices demonstrate statistically significant positive trends at confidence levels of 99.9% and 100, respectively, for the future period. Assessment of local perceptions of climate change in Dosso aligns with the study's findings, with respondents identifying droughts, floods, and heat waves as the primary extreme events. The analysis underscores that groundwater resources are the most significantly impacted by climate change in Dosso, followed by agriculture and livestock. This study offers valuable insights for rural project planners, policymakers, researchers, and local communities to develop effective adaptation strategies in response to the current and future impacts of climate change in the Dosso region of Niger