Temporal and Spatial Patterns of Droughts Based on Standard Precipitation Index (SPI) in Liaoning Province in Recent 54 a
Liaoning province is one of the severe drought areas. The study of the spatial-temporal distribution characteristics of drought in the region has positive significance to effectively response to drought, to take defensive measures and to reduce the harm of drought. This research analyzed nearly 54 years drought spatial-temporal characteristics distribution in Liaoning Province on the basis of the precipitation data of 52 meteorological stations from 1961 to 2014 by using standardized precipitation index (SPI), empirical orthogonal function (EOF) and rotated empirical orthogonal function (REOF). The results showed that the drought mainly occurred in the 1960s to the beginning of 1970 s, in the late 1970 s to early 1980 s, in the late 1980 s to early 1990 s and at early 21st century in Liaoning Province. Spring drought and autumn drought had the largest range, the longest duration time, and the most number of years, the range of winter drought happened less, and summer drought had the smallest range, and the least number of years. According to the result of REOF, the drought area in Liaoning Province can be divided into the northwest area, the central and northeast area, and the southeast area. Referring to the mean SPI12 of the divided areas, the results showed that the variation tendency of the mean SPI12 of the three areas was mainly the same, but there were also differences. The most obvious difference was the difference between the northwest area and the southeast area. The number of years of drought in the three areas was mainly the same. And for the drought period, both the southeast area and the central and northeast area had a long drought period each, the northwest area had two long drought periods, and the number of drought period in this area that reached middle drought or higher was the least compared to other two areas.
droughtStandardized Precipitation Index(SPI)Empirical Orthogonal FunctionRotated Empirical Orthogonal Function
国家科技期刊平台
NSTL
万方数据
维普
