AN ASSESSMENT OF FUTURE CLIMATE CHANGE IN NORTH WEST NIGERIA USING DOWNSCALED CLIMATE MODEL SIMULATIONS.

ABDUSSALAM Auwal Farouk

The sub-Saharan Africa has been classified vulnerable to climate change and variability. Northwestern Nigeria is located in this region and is expected to be disproportionately affected due to the vulnerability of its populations. Future climate change in northwestern Nigeria for two time slices was assessed using thirteen statistically downscaled global climate model projections from the Coupled Model Intercomparison Experiment Phase 5 (CMIP5) for Representative Concentration Pathway (RCP) 2.6, 6.0 and 8.5 scenarios. The results show that the ensemble mean captures the observed seasonal cycle and magnitude of maximum and minimum temperature, rainfall, and humidity with remarkable accuracy. In the near future (2020-2035) maximum temperature increases of about 0.5-1oC are statistically significant (p<0.01), while in the far future (2060-2075) maximum temperature increases of 1-3oC occur in 9-of-12 months (p<0.01), and increases are also significant (p<0.1 or 0.05) in the other three months. Humidity does not change significantly in the near or distant future except for a small but significant increase in December of about 1% (p<0.10; 2020-2035) to 2% (p<0.05; 2060-2075). While rainfall, exhibits statistically significant changes during December and January in both future periods but rainfall amounts is nearly zero during these months already, so the changes are almost imperceptible.

Key words: Climate change, CMIP5, Downscaling, North West Nigeria.