Spatiotemporal characteristics of precipitation and extreme events on the Loess Plateau of China between 1957 and 2009

Abstract

Abstract:Spatiotemporal trends in precipitation may influence vegetation restoration, and extreme precipitation events profoundly affect soil erosion processes on the Loess Plateau. Daily data collected at 89 meteorological stations in the area between 1957 and 2009 were used to analyze the spatiotemporal trends of precipitation on the Loess Plateau and the return periods of different types of precipitation events classified in the study. Nonparametric methods were employed for temporal analysis, and the Kriging interpolation method was employed for spatial analysis. The results indicate a small decrease in precipitation over the Loess Plateau in last 53 years (although a Mann-Kendall test did not show this decrease to be significant), a southward shift in precipitation isohyets, a slightly delayed rainy season, and prolonged return periods, especially for rainstorm and heavy rainstorm events. Regional responses to global climate change have varied greatly. A slightly increasing trend in precipitation in annual and sub-annual series, with no obvious shift of isohyets, and an evident decreasing trend in extreme precipitation events were detected in the northwest. In the southeast, correspondingly, a more seriously decreasing trend occurred, with clear shifts of isohyets and a slightly decreasing trend in extreme precipitation events. The result suggests that a negative trend in annual precipitation may have led to decreased soil erosion but an increase in sediment yield during several extreme events. These changes in the precipitation over the Loess Plateau should be noted, and countermeasures should be taken to reduce their adverse impacts on the sustainable development of the region.

Recent changes in extreme precipitation and drought over the Songhua River Basin, China, during 1960–2013

“…The non-parametric Mann-Kendall trend test (MK) was applied to analyze the temporal variations in extreme events because it is simple, robust method that addresses missing values and values below the examination threshold (Fu et al, 2004;Wan et al, 2013;Zhang et al, 2011b). The method has been recommended by the World Meteorological Organization (WMO) as a standard procedure for examining trends in hydrometeorological data that are serially independent (Hamed and Ramachandra Rao, 1998).…”

“…In China, trends in extreme precipitation have been documented in several studies, which showed that the occurrence of precipitation extremes increases at the national scale and exhibits apparent regional differences Liu et al, 2014;Liu et al, 2013;Qian et al, 2007;Su et al, 2008;Wan et al, 2013;Wang et al, 2013;Wang et al, 2008;Yang et al, 2008;You et al, 2008;Zhai et al, 1999;Zhang et al, 2011a). For example, Qian et al (2007) found that the frequencies of extreme rain events increased in eastern China centered on the middle-lower reaches of the Yangtze River but decreased in North China and Southwest China.…”

Trends of streamflow, sediment load and their dynamic relation for the catchments in the middle reaches of the Yellow River over the past five decades

“…Monthly precipitation data were obtained from the State Meteorology Bureau of China. Monthly precipitation data are spatially interpolated using the ordinary Kriging method (Wan et al, 2011). The area-weighted method is used to compute the monthly precipitation in each catchment.…”

Spatiotemporal Analysis of Extreme Hourly Precipitation Patterns in Hainan Island, South China

“…This method has the advantages of not requiring a given data distribution and not being affected by outlying data, and has been used entensively to test trends in hydrometeorological data, including temperature, rainfall and runoff time series [13][14][15][16]. In this study, the M-K method was used to test the trend stability of extreme precipitation time series.…”