Spatial and temporal characteristics of drought and flood disasters in Liaohe River basin in recent 53 years
In view of the frequent occurrence of drought and flood events in the Liaohe River basin un-der the background of climate change,the Z-index method was used to characterize the drought and flood events based on the daily surface precipitation data set V3.0 provided by the National Meteoro-logical Center.The combined empirical mode decomposition method(EEMD)was used to analyze the distribution characteristics and periodicity of drought and flood events in the Liaohe River basin from 1968 to 2020.The results show that:①Drought and flood events occurred in the Liaohe River basin in the past 53 years,accounting for more than 2/3 of the total time series,concentrated in the 1980s,the middle and late 1990s and the 2000s.②In the past 53 years,severe drought or flood e-vents were most serious in the lower reaches of the river and the estuary area in the southeastern part of the river basin,waterlogging was the most serious in the eastern mountainous area of the river ba-sin,and the phenomena of drought and waterlogging were milder in the middle and lower reaches of the Liaohe River basin.The contrast of drought and flood degree is the strongest in the southeast of the basin.③For the drought and flood events in the Liaohe River basin,the periodic characteristics are mainly short-time and high-frequency oscillations,and the contribution rate of decadal scale fluc-tuations to the periodic rule is relatively low.
Liaohe River basindrought and flood eventsensemble empirical mode decompositiondisaster frequency
NETL
NSTL
万方数据
