南海上层盐度对台风“莎莉嘉”的响应研究

"莎莉嘉(1621号)"是2016年的超强台风,本文利用高分辨率下的海气耦合模式COAWST再现了这个台风过程,并结合台风过境时间段内5d一次的ARGO数据综合分析了台风过境所引起的南海上层盐度的变化规律。研究结果表明,台风对海洋的影响作用具有一定的延迟性和持续性,约在台风中心过境1d后盐度变化达到最大值。台风过境总体上会使海区内上层盐度升高,最高可达0.4左右,台风路径右侧盐度升高幅度大于左侧,具有明显的右偏性,盐度变化中心相对台风路径偏移距离约50km。影响海洋上层盐度变化的因素有:台风强度、盐度分布结构和降水。台风强度越大,蒸发、抽吸和混合作用越强,盐度变化越大。台风会引起海洋盐度分布结构水平和垂向的显著改变,使高盐区或低盐区发生显著转变。而降水则会使上层盐度降低,所以台风过境海区内的盐度变化是多种因素共同作用的结果。

Response of the upper salinity to the super typhoon Sarika in the South China Sea

Typhoon Sarika(1621)is a super typhoon in 2016.This paper reconstructs the typhoon process by using COAWST,a high resolution ocean-atmosphere coupling model,and analyzes the variations in upper salinity in the South China Sea caused by the typhoon in combination with the ARGO data once every five days during the typhoon transit period.The results show that the impact of the typhoon on the ocean’s role is delayed and persistent,about 1 days after crossing the typhoon center,and the salinity change reached the maximum.The typhoon will make overall sea salinity in the upper layer,the maximum is up to about 0.4.The salinity increased in the right of the typhoon path is larger than the left side obviously,and the center offset distance is about 50 km.The factors affecting the salinity of the upper layer include typhoon intensity,salinity distribution structure and precipitation.The stronger the typhoon intensity,the stronger the evaporation,pumping and mixing,and the greater the salinity change.The typhoon will cause significant changes in ocean salinity distribution structure in horizontal and vertical direction,and the high salt area or low salt area changed significantly.The precipitation will make the salinity decrease,so the changes in sea salinity is the result of many factors.