%0 Journal Article %A PENG Zicheng %A %A CHEN Tegu %A NIE Baofu %A LIU Guijian %A HE Jianfeng %A CHENG Jiman %T The Variability of Winter Monsoon Intensity in Xisha Waters, South China Sea for the Last More Than 50 Years %D 2003 %R 10.11821/xb200305010 %J Acta Geographica Sinica %P 721-726 %V 58 %N 5 %X

We have used correlative analysis between 1958-1997 mean December-January- February NE winter monsoon velocities, measured at the Yongxing Island Observatory, as a winter monsoon intensity index (WMI) and mean δ18O data for corresponding months from Porites lutea coral, collected in the northern part of the South China Sea, to obtain a linear equation: WMI (m/s) = -4.913-2.138δ18O (‰), r = 0.83, n = 40. The high correlative coefficient between the above-mentioned two series of WMI and δ18O data is made by using high-pass filtering method. On the basis of the calculated WMI sequence from 1944 to 1977, the interdecadal variability shows that the WMI series decreases in the 1940s-1960s, slightly increases in the 1970s, but decreases again in the 1980s-1990s. The interannual variability reveals that the WMI series decreases obviously from 1944 to 1977 with the correlative equation of WMI (m/s) = 79.69-0.0377 Year, r = 0.68, n = 54. The linear slope is negative, which means that the WMI series decreases by about 0.4 m/s every 10 years. The power-spectral analysis displays that a 54-year WMI series is provided with periodicity of a 2.5-7 year band, which is related to the QBO band of 2-2.4 years and ENSO band of 3-8 years. Therefore, it can be considered that the winter monsoon variability in the South China Sea is also controlled by the global change.

%U https://www.geog.com.cn/EN/10.11821/xb200305010