INVESTIGATION OF THE VARIATION TRENDS OF PRECIPITATION IN LAST 50 YEAR IN NORTHERN KAROON WATERSHED OF IRAN
International Journal of Agricultural Science and Research
The hydrological parameters of rainfall, evaporation and runoff are influenced by the global warming as a new challenge in the world which affects on natural resources especially water sources. Climate change has many effects on hydrological cycle and consequently water resources and frequency and intensity if drought and flood in natural environment, society and economic. So, evaluating the variations in spatial and temporal pattern of precipitation is necessary to manage water resource in a
... gion. The objective of this research was to assess the trend of the precipitation variations using Mann-kendall and Sen test in monthly, seasonal and annual scale and determine the variations and its direction using CUMSUM chart in last 50 year in northen Karoon watershed. Results showed that the annual precipitation of watershed has increased, but this increasing was not significant. As, 90%of stations shows the increasing trend in annual precipitation, but only 18% of stations has significant trend. In seasonal scale the maximum increasing in precipitation was observed in autumn and the maximum decreasing trend in precipitation was recorded in spring. The maximum increasing trend in precipitation was recorded in December, whereas the maximum decreasing trend in precipitation was recorded in October and March. Annual variations in precipitation have been only occurred in Hana, MasjedSoleiman and PoulZaman-khan stations which is for the end of the forth decade to the prime of sixth decade. The results of this study are used to predicting and locating the future drought and scheduling and managing water resources of region.