Document Type : Original Article
Authors
1 PhD Student in Agricultural Meteorology, Shiraz University, Shiraz, Iran.
2 Professor, Department of Water Engineering, Shiraz University, Shiraz, Iran.
3 Assistant Professor, Department of Water Engineering, Shiraz University, Shiraz, Iran
Abstract
Since in the previous evaluations, the statistical trend of Iran's rainfall has fluctuated for 40 to 50 years, the purpose of this article is to make a long-term time series of Shiraz and then evaluate the rainfall trend of Shiraz in a long-term period of 98 years. The statistics of three stations The old meteorology of Shiraz was collected from the old sources and the water and synoptic organization of Shiraz as new sources. The time period of these two periods is 1302-1345 and 1346-1400, respectively. The randomness and homogeneity of the data were checked using the Run test. To measure the continuity of the averages of two statistical periods, two parametric and non-parametric t-Student and Mann-Whitney methods were used, respectively. Investigations showed that the data of the regional water company can be seen as a sequence of rainfall observations made at the stations of the British Consulate and Moshir Kohane Street and Third Army Street, and the 98-year time series is the longest. Made the statistical course. Using the non-parametric Mann-Kendall test and the slope of the age line, the trend in the time series was investigated. The findings indicated that the annual rainfall data and rainfall anomaly do not have a significant trend. Rainfall in spring and summer has an upward trend, but no trend was seen in winter and autumn.
Keywords
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