Variations in extreme precipitation and relation to the Asia summer monsoon over the Qinling-Dabashan Mountains, China

Abstract

The variations in extreme precipitation and their relation to large-scale climate circulation were investigated over a typical transitional climate zone named the Qinling-Dabashan Mountains from 1961 to 2018. In this study, the spatial and temporal variations in eleven extreme precipitation indices are determined using the Sen’s method, Mann test and heuristic segmentation method. The relations between extreme precipitation and the Asia summer monsoon are analyzed by cross wavelet transform methods. The major findings of this research are as follows: (1) the spatial distribution of extreme precipitation changes over time in the Qinling-Dabashan Mountains: higher precipitation intensity occur in the middle and southeastern regions, while other regions exhibit adverse variation patterns. (2) Temporally, the regional trends of only the annual total wet day precipitation are dominant in the Qinling-Dabashan Mountains and its subregions. However, the regional trends of extreme precipitation are not statistically significant. In addition, the extreme precipitation in the Qinling-Dabashan Mountains and its subregions was sensitive to environmental changes from 1961 to 2018, including intensive human activity, the Asian summer monsoon and steep terrain. Sensitivity to environmental change im-plies flash floods and other natural disasters from 1961 to 2018. (3) The East Asian Summer Monsoon has a stronger influence than the South Asian Summer Monsoon on extreme precipitation. The results of this research will aid decision-makers in their response to recent climate change scenarios in the Qinling-Dabashan Mountains.