Evaluation of Spatiotemporal Characteristics of Precipitation Extremes Variations in Amur River Basin

Abstract

Between 25th July and 19th August 2013, Amur River basin received some of its most extreme precipitation on record. The floods caused by the heavy rain brought affected Amur River and its 4 major tributaries. Hailun and Hailar stations break daily maximum precipitation record with 153.6 mm in 30th July, and 85.8 mm in 27th July, respectively. Based on daily precipitation observations at 25 stations from 1954 to 2014, the trends, periodicities and abrupt changes of five extreme precipitation indices in Amur River basin were investigated to the Spatiotemporal Characteristics of the extreme precipitation. Areaaveraged annual total wet-day precipitation (PRCPTOT), maximum 1-day precipitation amount (Rx1day), maximum 5-day precipitation amount (Rx5day), very wet days (R95) and extremely wet days (R99) had non-significant trends. By wavelet analysis for annual PRCPTOT, Rx1day, Rx5day, R95 and R99 series, the real part wavelet phase of main periods were mostly located at positive peaks in 2013, which were corroborated by abrupt change analysis. Multi-cycle superimposition of main periods is possibly the main cause for extreme precipitation in 2013. The record-breaking daily precipitation data improve 100-year recurrence interval (111.47 mm) to 130.61 mm in Hailun and raise 100-year recurrence interval from 78.95 mm to 87.91 mm in Hailar.

Analysis of Meteorological Element Variation Characteristics in the Heilongjiang (Amur) River Basin

“…In the summer of 2013, the Songhua River Basin experienced the most extreme precipitation in the region since 1984, leading to a dramatic increase in river flow and causing an unprecedented large-scale flood in the Amur River Basin. Yan Bo et al [14] used the extreme precipitation-induced flood event in the Amur River Basin in 2013 as a research background. They analyzed nearly 60 years of precipitation data from 25 meteorological stations in the basin, calculated the trends of extreme indices using the Mann-Kendall test, and explored the spatiotemporal characteristics of extreme precipitation events through wavelet transform analysis of extreme indices.…”