Spatial and Temporal Distribution Analysis of Late Spring Cold in Henan Province Based on EEMD Method
Xu Yanyan
Chang Jun
Abstract：Based on the 1961-2014 observation data of daily temperature from 100 meteorological stations in Henan province,and combining with the late spring cold (LSC) division standard,this paper establishes the time series of LSC's frequency and analyzes the spatio-temporal characteristics of LSC in Henan province based on EEMD and Mann-Kendall method.The result showed that the frequency of LSC basically presented a gradually increasing pattern from southwest to northeast.Although the 2-3 times LSC presented a north less south more space pattern.The total number of LSC was more in central Henan,where inclined to more severe LSC.IMF1 modal and the trend of cardinal reflected the evolution law of LSC by analysis of the EEMD.Henan LSC's frequency had an obvious quasi periodic oscillation for five years,and the trend of the frequency decreased significantly.Year 2000 and 2005 were the mutation points,under the climate background of the spring heating LSC's frequency began to decrease.
Keywords：late spring coldEEMDabrupt change analysisspatial and temporal distribution
Publication Date：2017-07-02
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：5( 28-32 )