Climatic characteristics of hourly precipitation (1978–2019) in the Poyang Lake Basin, China

摘要

This study analyzed the distribution and variation characteristics of hourly precipitation in the Poyang Lake Basin during 1978–2019. Most precipitation in the study area occurred during March–June. Short-duration precipitation events (1–6?h) accounted for 73.6% of the total. The average annual number of precipitation hours in the study area was 1028, 36 of which were heavy precipitation events, and both indices showed significant upward trends. The average hourly precipitation intensity in the study area was 1.58?mm/h, with an average of 28.6?mm/h in heavy precipitation events, and both indices showed increasing trends but with lower rates of change. On average, 202 precipitation events occurred annually with a speed of increase of 0.6 times/yr and a rate of growth of 3.0%/decade. Spatially, there have been significant increases in hours of precipitation and frequency of precipitation events at most stations in the northern Poyang Lake Basin, and a significant increase in heavy precipitation at some stations in eastern parts of the central region. It is imperative that effective disaster prevention and reduction measures are adopted in this area to mitigate the effects of heavy precipitation.