| 摘要: |
| 基于流域内的3个气象站点1960-2020年逐日最高气温、最低气温和降水量等基础资料，采用线性倾向回归分析法、Mann-Kendall突变检验法和小波分析等方法进行研究，分析和揭示了澜沧江上游流域在时间尺度上的变化。研究结果表明：(1)在1960-2020年，澜沧江上游流域的极端气温暖昼日数(TX90P)和暖夜日数(TN90P)呈显著上升趋势，速率分别为1.6d/10a和2.7d/10a；冷昼日数(TX10P)和冷夜日数(TN10P)呈显著下降趋势，速率分别为1.2d/10a和2.7d/10a，而极端降水变化只有持续湿润指数(CWD)的变化趋势不显著，其余三个降水指标降水总量(PRCPTOT)、1日最大降水量(RX1day)、5日最大降水量(RX5day)都呈显著上升趋势，速率分别为18.8mm/10a、0.5mm/10a和0.8mm/10a。(2)澜沧江上游流域极端气温指数冷昼日数(TX10P)在1992年出现突变点，冷夜日数(TN10P)在1978-1993年间出先了连续突变现象，极端气温指数降水总量(PRCPTOT)在2000年以后发生突变，这也说明了在时间尺度上的变化明显。(3)在1960-2020年，澜沧江上游流域的极端气温和极端降水周期特征变化显著，均存在多时间尺度的特征，第一主周期主要在10-15a、15-20a和25-30a三个时间尺度范围内。 |
| 关键词: 澜沧江上游；极端气温；极端降水；小波分析 |
| DOI： |
| 投稿时间：2022-03-01修订日期：2022-05-19 |
| 基金项目:国家自然科学基金项目 |
|
| Study on the variation characteristics of extreme temperature and extreme precipitation in the upper reaches of Lancang River Based on meteorological stations |
| lizhenzhong,xumin,songxuanyu |
| (Lanzhou Jiaotong University;Northwest Institute of ecological environment and resources, Chinese Academy of Sciences) |
| Abstract: |
| Based on the basic data of daily maximum temperature, minimum temperature and precipitation from 1960 to 2020 at 3 meteorological stations in the basin, linear tendency regression analysis, Mann-Kendall mutation test and wavelet analysis were used to analyze and reveal the upper Lancang River basin on the time scale. The results show that (1) from 1960 to 2020, the extreme temperature trends in the upper Lancang River basin are significant, with warm day days (TX90P) and warm night days (TN90P) showing a significant upward trend with an increasing rate of 1.6d/10a and 2.7d/10a, respectively; cold day days (TX10P) and cold night days (TN10P) showing a significant downward trend with a decreasing rate of 1.2d/10a and 2.7d/10a, respectively. Only the trend of extreme precipitation change is not significant for the continuous wetness index (CWD), while the remaining 3 precipitation indicators, total precipitation (PRCPTOT), 1-day maximum precipitation (RX1day), and 5-day maximum precipitation (RX5day), show significant increasing trends, with an increasing rate of 18.8mm/10a、0.5mm/10a and0.8mm/10a. (2) The number of extreme temperature index cold days (TX10P) in the upper Lancang River basin showed a sudden change point in 1992, the number of cold nights (TN10P) showed a continuous sudden change from 1978 to 1993, and the total extreme temperature index precipitation (PRCPTOT) showed a sudden change after 2000. This also indicates a significant change in the time scale. (3) During 1960-2020, the characteristic of the extreme temperature and extreme precipitation cycles in the upper Lancang River basin has changed significantly, both on multiple time scales, with the first main cycle mainly within 3 time scales of 10-15a, 15-20a and 25-30a. |
| Key words: Upper Lancang River Basin；Extreme temperature；Extreme precipitation；wavelet analysis |
