Coherent modes in multi-scale variability of precipitation over the headwater catchments in the Pearl River basin, South China
Coherent modes in multi-scale variability of precipitation over the headwater catchments in the Pearl River basin, South China
复制标题
华南珠江流域源头降水多尺度变化的相干模态
DOI：
10.1002/hyp.11078
复制
发表时间：
2017-02-01
影响因子：
3.2
通讯作者：
Sivakumar, Bellie
中科院分区：
文献类型：
--
作者：
Niu, Jun;Chen, Ji;Sivakumar, Bellie
本文研究了华南珠江流域源头流域降水多尺度变化的相干模式。研究了流域内 16 个流域的长期（1952-2000 年）日降水量空间平均数据。执行小波变换分析以捕获嵌入在时间序列中的不同时间时间尺度（从 6 天到 8.4 年）的波动。使用降水小波谱的主成分分析来描绘相干模式的集水簇。结果表明，多达 98% 的降水变率只能由两种相干模式来解释：高小尺度模式和高季节模式。结果还表明，绝大多数流域（即 16 个流域中的 15 个）在研究的三个子时期（1952-1968、1969-1984 和 1985-2000）中表现出一致的多尺度变异模式特征。还讨论了相干模态对区域洪涝和干旱趋势的潜在影响。
This paper studies the coherent modes of multi-scale variability of precipitation over the head-water catchments in the Pearl River basin in South China. Long-term (1952-2000) daily precipitation data spatially averaged for 16 catchments in the basin are studied. Wavelet transform analysis is performed to capture the fluctuation embedded in the time series at different temporal time-scales ranging from 6 days to 8.4 years. The catchment clusters of the coherent modes are delineated using the principal component analysis on the wavelet spectra of precipitation. The results suggest that as much as 98% of the precipitation variability is explained by only two coherent modes: high small-scale mode and high seasonal mode. The results also indicate that a large majority of the catchments (i.e., 15 out of 16) exhibit consistent mode feature on multi-scale variability throughout three sub-periods studied (1952-1968, 1969-1984, and 1985-2000). The underlying effects of the coherent modes on the regional flood and drought tendency are also discussed.