Observed Long-Term Climatic Variability and Its Impacts on the Ground Water Level of Quetta Alluvial

Water is an important natural resource. Groundwater is one of most vital and consistent source of renewed water globally containing areas which have extreme rainfall and abundant of surface water. This study assesses the climate impact on groundwater level using the precipitation, temperature data from 1946 to 2015, evapotranspiration, and monthly groundwater levels from 1987 to 2013 in Quetta Valley, Balochistan. The annual precipitation analysis identifies decreasing trends at all the gauging stations. The sharp increase in maximum temperature was observed during the late 90s. Similarly, mean monthly minimum temperature was observed well below normal 1947-1987, and afterwards, a sharp increase in minimum temperature was observed which was well above normal. The annual evaporation data analyzed which identified increasing trends at all the stations except Quetta city, where it has been decreased. The trends are found to be statistically significant at all the stations except Quetta city. Similarly, the rain data of different time periods have also been examined with the perspective to study its impact on the groundwater levels. The analysis explores the fact that the groundwater is continuously depleting due to variability in rainfall. The result also illustrates that groundwater level is decreasing day by day and the rainfall temporary influences for a very short time period on the groundwater level depending upon the consumption.