Analysis of spatiotemporal characteristics of precipitation at different levels in Beijing based on Mann–Kendall test and wavelet analysis

Abstract

This paper employs Mann–Kendall test, wavelet analysis, and Kriging interpolation to analyze Beijing's precipitation from 1981 to 2022, using 20-station data. It reveals precipitation trends: increase 1980s–1990s, decline, and then rebound in the 2000s, especially in rainstorms. A 2008 turning point marked a shift from decreasing to increasing trends. Annual variation correlates with intensity, while moderate-to-torrential rain changes are linked to days. Beijing's precipitation exhibits multi-timescale periodicity, with similar trends in annual and rainstorm precipitation. Future predictions suggest a decrease. Spatially, northeast receives more rain than southwest, mountains more days than plains/cities, and east has stronger intensity than west. Moderate rain dominates total precipitation, with occurrence declining as intensity increases. Annual precipitation positively correlates with grades but negatively with days. These insights deepen our understanding of Beijing's complex precipitation patterns.