[1]LIU Ruilin,SUN Peng,ZHANG Qiang,et al.Characteristics of Non-Stationary Meteorological Drought in Hengduan Mountains Based on Copula[J].Research of Soil and Water Conservation,2022,29(01):213-223.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
29
Number of periods:
2022 01
Page number:
213-223
Column:
Public date:
2022-02-20
- Title:
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Characteristics of Non-Stationary Meteorological Drought in Hengduan Mountains Based on Copula
- Author(s):
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LIU Ruilin1,2, SUN Peng1,2, ZHANG Qiang3,4, BIAN Yaojin1,2, MA Zice1,2, ZOU Yifan1,2, LYU Yinfeng1,2
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(1.School of Geography and Tourism, Anhui Normal University, Wuhu, Anhui 241002, China; 2.State Key Laboratory of Earth Surface Processes and Resource Response in the Yangtze-Huaihe River Basin, Wuhu, Anhui 241002, China; 3.Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; 4.Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China)
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- Keywords:
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NSPEI; theory of run; Copulas function; return period
- CLC:
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P467
- DOI:
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- Abstract:
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In order to reflect the temporal and spatial evolution characteristics of drought in the Hengduan Mountains under the background of climate change, meteorological drought was expressed by NSPEI obtained based on the monthly meteorological data of 94 meteorological stations in the Hengduan Mountains from 1961 to 2019, and the joint distribution of drought characteristics under different return periods in the Hengduan Mountains were revealed by using the run theory, univariate and multivariate Copula methods. The results showed that:(1)the frequency of drought in the Hengduan Mountains was 33% to 80%, and the frequency of drought in the south was higher than that in the north; with respect to different drought levels, the frequency of mild drought was 48% higher than that of extreme drought, the severe and extreme droughts mainly concentrated in the south, and light drought and moderate drought occurred in the whole Hengduan Mountains, but the frequency was still higher in the south than that in the north; there was spatial difference in drought level at different monthly scales in Hengduan Mountains; the level of drought in autumn and summer was less than that in winter and spring, and the level in March was higher than other months, with the level of drought ranging from 20.97 to 38.10;(2)the generalized Pareto distribution function(GP)was the optimal fitting univariate distribution function of drought duration, the generalized extreme distribution function(GEV)was the optimal fitting univariate distribution function of drought severity, and the Gaussian function was the optimal fitting Copula distribution function;(3)the spatial distribution characteristics of drought severity was almost the same with drought duration. the probability of long duration and high severity in the south was less than that in the north; drought duration that occurred more than once in a decade could last more than a year, and droughts severity that occurred more than once in fifty years could last more than one hundred. The spatial distribution was influenced by latitude in the northern of Hengduan Mountains, and presented the east-west distribution, while the distribution in the center and south presented the north-south distribution, which was mainly restricted by the longitudinal mountains and valleys.(4)drought duration >10.07, drought intensity>36.96, the joint return period >0.01, co-occurrence return period <0.01, meant joint return period>predetermined return period>co-occurrence return period. The joint return period in the central and western margin of Hengduan Mountains was higher than that other areas, and the spatial distribution of the co-occurrence return period was opposite to the joint return period. In general, the drought frequency in southern part of Hengduan Mountain was higher than that in the northern part, and the drought level in the northern part was higher than that in the southern part. Meanwhile, the drought risk in the northern part was higher than that in the southern part under different return periods. Therefore, the attention should be paid to the prevention of drought risk in the northern part of Hengduan Mountain region in the future.