Investigation and analysis of Iran's annual temperature and precipitation trend (2017-1988)

this research, the annual rainfall and temperature trends of the country were evaluated using annual rainfall data of 115 synoptic stations during the period of 30 years (2017-1988). The average precipitation of the station and Tissen were calculated for each year. Using the nonparametric statistical method of Kendall-Mean method, the mean rainfall and temperature trend, and the age line slope estimator, the trend line tilt rate were tested. The results showed that there was not a ascendant or significant decrease trend in the mean precipitation in 99% and 95% confidence levels, but this trend was significant at 90% confidence level.However, the average precipitation rate of the country is about 2.1 mm per year, and the average precipitation Tissen of Iran has dropped by about 2.2 mm Also, the results showed that in the time series of the average station temperature and temperature in the country, the incremental temperature of the station is 0,252 ° C per year, which is significant at 95% confidence level. The average temperature of the country has been increased by Tissen at around 0.05 degrees Celsius per year, which is an increase in the 99% confidence level.