Time Scale Analysis of Precipitation Based on EMD Method in Xilin Gol

Xilin Gol is located in the north-central part of Inner Mongolia, and its western plains are extremely scarce areas of water resources.The analysis of the precipitation in Xilin Gol is of great significance to the economic development of local animal husbandry. Time series analysis and prediction have important practical application value, and scientific and accurate prediction results can provide a key guiding role for social activities. Combined with the fast Fourier transform, the empirical modal decomposition method was used to analyze the monthly precipitation data of Xilin Gol from 1961 to 2016.The results show that the time series has a period of 6 and about 22 months.And through the calculation of the contribution rate of the IMF variance, it is found that 12 months is the main cycle of the monthly precipitation of Xilin Gol,The results show that EMD can more accurately reflect the periodic characteristics of precipitation. The research results have certain practical value for the scientific and rational use of precipitation.