Reza Modarres - Faculty of Natural Resources, Isfahan University of Technology, Iran
Saeed Soltani - Faculty of Natural Resources, Isfahan University of Technology, Iran

Climate change has a lot of harmful influence on the environment. This influence is much harmful in sensitive arid and semi arid region. In this study the time series of annual and monthly total rainfall and the annual number of rain days of 25 stations in arid and semi arid region of Iran were analyzed to establish the existence of rainfall variability in this region. Results indicated statistically significant positive and negative trend at p<0.01 or p<0.05 by Mann-Kendall test. However, only 16% and 50% of stations showed significant trend in annual and monthly time scale, respectively. The results suggest that rainfall trend is locally affected different parts of the region rather than the entire region.

Rainfall, Trend, Mann-Kendall, Iran