Analysis of Historical Precipitation in Semi-Arid Areas – Case Study of Amman Zarqa Basin

Abstract

Climate change is determined as a severe threat to water resource availability in Semi-Arid Areas. Therefore, it is crucial to examine drought trends to develop and sustain water resources. This study evaluates the effects of climate change in Jordan by analyzing the long-term precipitation trends in Amman Zarqa Basin over the water years from 1971 till 2016. For the analysis, daily precipitation data were collected for six rainfall stations located throughout the basin. The standardized precipitation index (SPI) variations were investigated at monthly intervals. Control charts, hypothesis testing, t-test, differences of variances, and trend analysis were used to determine climatic trends. Results of the analysis indicated that the year 2003 marks an acceleration point in the rate of precipitation decrease. Additionally, a change in the precipitation pattern was observed as seasonal precipitation contribution varied for the pre-2003 period compared to the post-2003 period.

Keywords

• precipitation
• climate change
• standard precipitation index (spi)
• semi-arid