Projected intensification of precipitation characteristics and meteorological drought and wetness conditions in Accra Ghana

Meteorological droughts, wet conditions, and extreme precipitation events pose increasing risks to rapidly urbanizing coastal cities such as Accra, Ghana, where flooding, drought, and water-resource stress remain major planning challenges. This study assessed historical and future precipitation characteristics in Accra using the Korea Meteorological Administration Advanced Community Earth System (KACE) model under the SSP1-2.6 and SSP5-8.5 climate scenarios. Historical model performance was evaluated against observed precipitation data for 1982–2014, while future changes were examined for the near (2015–2040), mid (2041–2070), and far (2071–2100) future periods. Drought and wetness conditions were evaluated using the Standardized Precipitation Index (SPI), while precipitation characteristics were assessed using the Expert Team on Climate Change Detection and Indices (ETCCDI) metrics of consecutive dry days (CDD), consecutive wet days (CWD), maximum 1-day precipitation (Rx1day), maximum 5-day precipitation (Rx5day), and the simple daily intensity index (SDII). Results indicate that the KACE model reproduces the general historical precipitation pattern, although differences remain in the magnitude of some extreme events. Future projections indicate continued variability in SPI, CDD, CWD, Rx1day, Rx5day, and SDII across emission scenarios and future periods. Rather than indicating a simple shift toward wetter or drier conditions, the results reveal the continued occurrence of both meteorological drought and wetness conditions, increasing recurrence and persistence of dry and wet events at longer time scales, and a stronger late-century rainfall-intensity signal under SSP5-8.5. These findings provide valuable information for climate adaptation planning, flood-risk reduction, urban drainage design, and sustainable water-resource management in Accra.