Temporal variations characteristic of precipitation in the Three Gorges Reservoir area from 1961 to 2016

Abstract

As a hot issue, the precipitation characteristics of the Three Gorges Reservoir (TGR) area drew widespread interest from domestic and overseas academic circles. Based on China's surface-based meteorological monthly precipitation data from 1961 to 2016 in the TGR area, the spatial, inter-annual and inter-decadal, and multi-time-scale changes of precipitation in the TGR area are analyzed by using Collaborative Kriging (Co-Kriging, CK) Interpolation, linear regression analysis, Morlet wavelet analysis and 5-year sliding average processing, which provide the reference basis for further discussion on the impact of climate change, flood control and drought relief work in the reservoir area. Research shows that in the past 56 years, the average annual precipitation in most areas of the TGR ranges from 1,000 to 1,200 mm; the variation of precipitation in the TGR area shows a weak decreasing trend, with great fluctuation between year and generation, and the precipitation in each decade has a ‘less-more-less’ changing trend; the annual precipitation in the TGR area has periodic changes on multi-time scales, mainly including 25, 16 and 8 years. The smaller the scale the shorter the average period of precipitation change. HIGHLIGHTS The average annual precipitation of the TGR ranges from 1,000 to 1,200 mm.; Inter-annual and inter-decadal of precipitation shows a ‘less-more-less’ changing trend.; Multi-time scale changes of precipitation mainly including 25, 16 and 8 years.;

Keywords

• decadal change
• inter-annual change
• multi-time scale
• precipitation
• three gorges reservoir area