Abstract:
Spatiotemporal characteristics of number of precipitation days for different magnitudes and total precipitation during flood season were investigated based on daily precipitation data at 5 national surface weather stations on the north slope of east Tianshan Mountain from 1961 to 2016 (May to September). The results show that with the increase of precipitation magnitudes, the number of precipitation days decreases rapidly. The nearly 56 a total precipitation days, moderate rain days, heavy rain days and rainstorm days of all showed an increasing trend. The increase trend of the number of heavy rain days was the most obvious, which mostly caused the increase of total precipitation days. The number of light rain days showed an obvious decreasing trend. In 1991, the heavy rain days had a sudden change, and in 1980 the heavy rain days had a sudden change. The number of other precipitation days had a downward trend, but no abrupt change occurred. From the spatial distribution of the number of precipitation days of different orders of magnitude, the number of light rain days, the number of precipitation days were all based on the wooden barrier as the high value center decreased to the east and west gradually, and the lowest values were generally found in Yiwu and Jimusar. During flood season, with the increase of precipitation magnitudes, the correlation coefficient increased between the precipitation days and total precipitation. The correlation between the number of light rain days and total precipitation was the worst and the number of heavy rain days was the most obvious.