Assessment of the influence of climate change on desertification in Katsina state, Nigeria

This study investigated the influence of climate change on desertification in Katsina State between 2004 and 2024, with a focus on vegetation dynamics, climatic variability, and climate–vegetation interactions. MODIS satellite datasets (Normalized Difference Vegetation Index - NDVI) and meteorological records from NiMet were evaluated using the Modified Mann‒Kendall (MMK) trend test, coefficient of variation, Pearson correlation, and GIS-based weighted linear combination for desertification risk mapping. The results indicated that the vegetation density decreased somewhat between 2004 and 2014 but improved by 2024, whereas the vegetation condition (VCI) displayed steady degradation, resulting in widespread stress despite localized greening. Rainfall demonstrated inter-annual variability (419–938 mm); while the minimum and maximum temperatures increased significantly, indicating significant warming. The NDVI was strongly related to rainfall (r = 0.70, p < 0.001) and negatively correlated with the maximum temperature (r = − 0.68, p < 0.001), whereas the minimum temperature showed an insignificant correlation. Desertification risk mapping indicated a significant north–south gradient, with high to exceptional risk concentrated in the drier northern LGAs. These data show that climate change, represented by irregular rainfall and rising temperatures, has worsened vegetation stress and increased desertification hotspots in northern Katsina. Policy recommendations include afforestation, sustainable land management, enhanced water conservation, and irrigation.