Climate change and its effect on groundwater of Kazerun basin,Fars Province, Iran

Climate change could alter the natural trend of hydrologic processes including but not limited to changing precipitation amount and timing, air moisture, stream flow rates, lakes level, discharge and timing of springs and hence declining groundwater levels, deteriorating water quality, and increasing ecosystem losses. To investigate the trend of climate change and its effect on water crisis in Kazerun aquifer, the change-point years in monthly time series of precipitation, temperature and air moisture of six measuring stations, discharge rates of two hydrometric stations on Shapur River and the water level and Electric Conductivity (EC) of 43 piezometers are analyzed. The Pettitt-Mann-Whitney and Cumulative Sum tests were applied to determine the significance of the detected changes. The most probable change point in each time series was determined. Also, percent change in the time series after the change point was evaluated. The result indicates that 1998 is the most probable change-point years in the time series of precipitation, river discharge, temperature and air moisture content. Compared to the period before 1998, annual precipitation, river discharge and air moisture content havedecreased and temperature has increased. Seasonal precipitation amounts have generally decreased during autumn, winter and spring. The result also shows that the most probable change-point year in groundwater level was 2007-2008. This indicate that mismanagement, over-extraction and thirst for development are main causes for water crisis and the climate change has triggered the water crisis in the basin

Keywords:

Climate change , change-point , Mann-Whitney-Pettitt test , Water crisis.