Zhang, Dan; Chen, Peng; Zhang, Qi;
等.
Investigation of concurrent hydrological drought events is
helpful for understanding the inherent mechanism of hydrological extremes and
designing corresponding adaptation strategy. This study investigates concurrent
hydrological drought in the Poyang lake-catchment-river system from 1960 to 2013
based on copula functions. The standard water level index (SWI) and the standard
runoff index (SRI) are employed to identify hydrological drought in the
lake-catchment-river system. The appropriate marginal distributions and copulas
are selected by the corrected Akaike Information Criterion and Bayesian copulas
selection method. The probability of hydrological drought in Poyang Lake in any
given year is 16.6% (return period of 6 years), and droughts occurred six times
from 2003 to 2013. Additionally, the joint probability of concurrent drought
events between the lake and catchment is 10.1% (return period of 9.9 years).
Since 2003, concurrent drought has intensified in spring due to frequent
hydrological drought in the catchment. The joint probability of concurrent
drought between the lake and the Yangtze River is 11.5% (return period of 8.7
years). This simultaneous occurrence intensified in spring, summer and autumn
from 2003 to 2013 due to the weakened blocking effect of the Yangtze River.
Notably, although the lake drought intensified in winter during the past decade,
hydrological drought in the catchment and the Yangtze River did not intensify
simultaneously. Thus, this winter intensification might be caused by human
activities in the lake region. The results of this study demonstrate that the
Poyang lake-catchment-river system has been drying since 2003 based on a
statistical approach. An adaptation strategy should be urgently established to
mitigate the worsening situation in the Poyang lake-catchment-river
system.
来源:JOURNAL OF
HYDROLOGY 卷: 553 页: 773-784 出版年: OCT
2017