Recent Trends and Variability in Climatic Water Balance: Implications for Forestry Development in Ethiopia

This study investigated the climatology, trends, and variability of precipitation, reference evapotranspiration (ET o ), and climatic water balance (CWB) in Ethiopia and its 12 basins from 1980 to 2021. Mean annual rainfall was 773 mm, with significant regional variations, while the mean annual ET o was 958 mm. Kiremt (June–September) received the highest rainfall (393 mm), and Belg (February–May) exhibited high ET o . The annual mean CWB was −185 mm, with only four basins showing a positive CWB. Spatially, western Ethiopia experienced higher rainfall, while the northeast had higher ET o . Temporally, both annual rainfall (2.01 mm/year) and ET o (0.40 mm/year) significantly increased nationally, with regional variations. Rainfall variability was highest in the Bega (October–January) season (CV = 45.5%) and lowest in Kiremt (CV = 21.9%). CWB showed the highest variability. Years with moderate to extreme dry and wet conditions were identified through standardized rainfall anomaly analysis. These hydroclimatic patterns and their changes have significant implications for forestry development in Ethiopia, necessitating region‐specific strategies. Positive rainfall trends in western and southern basins offer opportunities for faster tree growth, while decreasing rainfall and negative CWB in the northeast pose challenges requiring drought‐tolerant species and water conservation. The increasing ET o and high interannual rainfall variability further emphasize the need for careful species selection and resilient forestry management practices across Ethiopia.