Changing climate patterns in Nampula district, northern Mozambique: a multi-decadal analysis of rainfall, temperature, and wind dynamics

Abstract Sub-Saharan Africa is one of the regions most exposed to climate change, and Mozambique is highly vulnerable due to its geographic setting and socioeconomic constraints. This study assessed long-term meteorological trends in the Nampula district, northern Mozambique, using a 43 year observational record (1980–2023) to support local climate-risk assessment and adaptation planning. Annual rainfall, minimum temperature, maximum temperature, relative humidity, and wind speed were analysed using the Mann–Kendall trend test and Sen’s slope estimator. Annual rainfall showed no significant long-term trend ( Z = −0.273, p = 0.785), indicating relatively stable precipitation totals over the study period. In contrast, both minimum temperature ( Z = 2.620, p = 0.009) and maximum temperature ( Z = 6.142, p < 0.001) increased significantly. For the calendar-year annual mean T max series, the estimated warming rate was 0.319 °C per decade, and endpoint-sensitivity tests indicated that this trend was not driven by the final year or years alone. Relative humidity declined significantly ( Z = −3.824, p < 0.001) at a rate of −0.78 percentage points per decade, while wind speed increased significantly ( Z = 3.560, p < 0.001) by 0.12 m s −1 per decade. These findings indicate intensifying atmospheric drying and evaporative stress despite the absence of a significant long-term decline in rainfall. The results suggest that climate risk in the Nampula district is strongly associated with warming and moisture-demand changes rather than with simple rainfall reduction, providing a robust empirical basis for adaptation planning in this agriculture-dependent region.