-
Abstract:
Based on the monthly precipitation data of 126 observation stations from 1961 to 2000 in Yunnan Province, the interannual and decadal variability of precipitation in rainy seasons are studied by using wavelet analysis. It is shown that there is a 2-6 year oscillation at the interannual time scales and a quasi-30 year oscillation at the decadal time scales. These periodic oscillations relate to the distribution of tropical heat content. When the precipitation is much more (less) than normal, the upper seawater is colder (warmer) in almost all the tropical Indian Ocean, and warmer (colder) in the western Pacific as well as colder (warmer) in the eastern Pacific. The key areas of the anomaly heat content distribution that have significant correlation to the Yunnan precipitation in rainy season are in the southern hemispheric Indian Ocean with a dipole pattern in the winter as well as in the deep basin of the South China Sea (SCS) before the Yunnan rainy season begins. Therefore, the anomalous distributions of the heat content in the southern Indian Ocean and the SCS In winter are good indicators for predicting drought or flood in Yunnan Province in the following rainy season.
-
References
[1]
|
WANG Bing, ZHAO Er-xu, ZHANG Ji-guang. The rainfall distribution of rainy season influenced by the Indian Ocean surface temperature [J]. Scientia Geographica Sinica, 1998, 2: 163-168. |
[2]
|
YAN Hong-ming, XIAO Zi-niu. Oscillation and distribution of precipitation during rainy season in southwest China and the relation between precipitation and SSTA over Indian Ocean [J]. Acta Meteorologica Sinica, 2001, 21(1): 54-63. |
[3]
|
WANG Yu, ZHANG Wan-cheng, ZHU Tian-lu. The basic feature of rainfall fields of May in Yunnan and its correlation with the SST of tropic Pacific [J]. Tropical Geography, 1996, 21: 324-331. |
[4]
|
CARTON J A, CHEPURIN G, CAO X, et al. A simple ocean data assimilation analysis of the global upper ocean 1950-1995, Part 1: methodology [J]. J. Phys. Oceanogr., 2000a, 30: 294-309. |
[5]
|
CARTON J A, CHEPURIN G, CAO X. A Simple Ocean Data Assimilation analysis of the global upper ocean 1950-1995 Part 2: results [J]. J.Phys Oceanogr., 2000b, 30: 311-326. |
[6]
|
TORRENCE C, COMPO G P. A practical guide to wavelet analysis [J]. Bull of American Meteorological Society, 1998, 79: 61-78. |
[7]
|
DUAN Xu, YOU Wei-hong, ZHENG Jian-meng. The drought and flood feature in Yunnan [J]. Plateau Meteorology, 2000, 19: 84-90. |
[8]
|
WEBSTER P J, MOORE A M, LOSCHNIGG J P, et al. Coupled ocean-atmosphere dynamics in the Indian Ocean during 1997-98 [J]. Nature, 1999, 401:356-359. |
[9]
|
WANG Bing, YUAN Chun-hong, XIAN Wen-long. Spectrum analysis between the sea temperature on the South China Sea and the rainfall in Yunnan [J]. Journal of Yunnan University, 1996, 21(3): 32-37. |
-
-
-