摘要: |
利用1966–2016年南川国家站的逐日降水观测资料,分析了南川降水的年内分布及次季节变化和暴雨的气候变化特征、年际、年代际和趋势变化特征。结果表明:南川降水的年内分布差异大,降雨量峰值出现在6月,月降水强度最大在7月;南川的降水具有明显的次季节变化,且准双周变化信号(10–25天)大于低频季节内振荡(25–90天);南川的暴雨日数和暴雨量与年降雨量有很好的正相关性;暴雨出现在3–11月,其分布呈单峰型,峰值出现在6月;年平均暴雨日为2.5d,暴雨日数年际变化的线性趋势不显著;暴雨日总降水量在1966–1994年存在10–12a的年代际变化信号,在1996–2016年主要存在13–15a的年代际变化信号,在1976–1984年还存在2–4a的年际变化信号;南川的暴雨特征量年际、年代际变化大,但没有显著的升降趋势,说明南川暴雨的总体气候特征是比较平稳的。 |
关键词: 暴雨,次季节变化,年际年代际变化 |
DOI: |
投稿时间:2018-12-05修订日期:2019-08-24 |
基金项目: |
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Multi-scale anaylsis for precipitation from 1966 to 2016 in Nanchuan Chongqing |
huangyuye |
(Chongqing Nanchuan Meteorological Bureau) |
Abstract: |
Based on the daily precipitation data of Nanchuan National Station during 1966–2016, the seasonal variability and intraseasonal oscillation of Nanchuan precipitation and the climatological, interannual, decadal variability and long-term trend of the storms in Nanchuan Station are investigated. It shows that the precipitation in Nanchuan has significant seasonal variability. The maximum precipitation is in June and the maximum precipitation intensity is in July. The precipitation in Nanchuan also shows intraseasonal variability, and its quasi-biweekly oscillation (10–25 days) is stronger than low-frequency intraseasonal oscillation (25–90 days). The storm days and storm rainfall quantum are positive related to the annual precipitation. Storms in Nanchuan Station occur during May–November with maximum in June. The annual mean of storm days is 2.5d and the long-term trend of annual storm days is not significant. The variability of storm rainfall has a 10–12a decadal signal during 1966–1994 and a 13–15a decadal signal during 1996–2016. There is also a 2–4a decadal signal during 1976–1984. However, there is no significant long-term change, which means the climate state of storm variability in Nanchuan is stable. |
Key words: storms,intraseasonal oscillation,interannual and decadal variability |