Max-stable based evaluation of impacts of climate indices on extreme precipitation processes across the Poyang Lake basin, China

Monthly precipitation extremes defined by monthly maximum one-day precipitation amount (Rx1 day) and maximum consecutive five-day precipitation amount (Rx5 day) were analyzed based on daily precipitation data covering a period of 1957 to 2010 across the Poyang Lake basin, the largest freshwater lake basin in the lower Yangtze River basin, China. Based on the max-stable, impacts of El Ni (n) over tildeo-Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Indian Ocean Dipole (IOD), Pacific Decadal Oscillation (PDO) on the annual and seasonal Rx1 day and Rx5 day regimes in the Poyang Lake basin were evaluated. Results indicated that annual Rx1 day and Rx5 day were influenced mainly by the ENSO events a year earlier and the relations between annual Rx1 day and Rx5 day and ENSO were statistically positive. However, influences of climate indices on the seasonal Rx1 day and Rx5 day are complicated when compared with the influences on annual Rx1 day and Rx5 day regimes. ENSO and PDO can enhance the spring Rx1 day regime of the subsequent year and the same year, respectively, but IOD weakens spring Rx1 day in the same year. In summer, ENSO can enhance Rx1 day of the subsequent year. However, Rx1 day in summer had a decreasing tendency. IOD and NAO influenced the autumn Rx1 day in another way, i.e., IOD decreases autumn Rx1 day of the subsequent year; while NAO enhances autumn Rx1 day of the same year. Meanwhile, ENSO can amplify the summer Rx1 day in terms of variability, while IOD and NAO can, respectively, influence autumn and winter Rx1 day in terms of mean. Influences of climate indices on annual and seasonal Rx5 day are similar to those on Rx1 day. Results of this study are of great theoretical as well as practical merit in terms of evaluation of droughts and floods under the influences of climate indices. (C) 2014 Elsevier B.V. All rights reserved.