The impact of future climate change on water availability in Gusau, Zamfara State, Nigeria

Abstract

Climate change has continued to pose challenging global environmental problems in the 21st century. For instance, studies have shown that water resources quantity and quality will be seriously degraded by the phenomenon. This paper examines the effect of climate change on future water availability in Gusau City, Zamfara State, Nigeria. The data obtained from three Regional Climate Models (RCMs) ensembles gridded at 0.5^o x 0.5^o spatial resolutions were used. The analysis was carried out using ArcGIS (ArcMap, version 10.5) software and comparison of the outcome of the three ensembles was made. The findings show future temperature increase as 1- 3^oC by 2040, 3^oC by 2070 and 2- 5^oC by 2100. Furthermore, future rainfall will increase under rcp 4.5 and 8.5 by 6.7% - 20%, 10% - 20% and 10% - 30% by 2040, 2070v and 2100 respectively. It further shows an increase of +10% to + 60% in seasonal changes of rainfall in the months of April-May-June and July-August-September respectively. These will ultimately result in the increase in surface run off and aquifer recharge. Similarly, the quality of water will also be degraded through sedimentation and nitrogen loading from farms, transport and dissolution of heavy metals by flooding. Therefore, the study recommends for the involvement in storm water harvesting and storage processes by both Government and other large scale water users.