摘要
在南海尚未有关于海洋大气边界层结构日变化方面的研究。研究海洋大气边界层,有利于我们更好地研究海洋表层结构变化影响机制,对发生在海洋大气边界层上的过程进行预测预报。因此了解南海海洋大气边界层的结构特征,对于我们进一步了解南海天气尺度海气相互作用有非常重要的意义。通过对1998年在南海南部(6°15′N,110°E)和南海北部(20°29′39″N,116°57′48″E)的南海季风试验中定点科考船释放一天四次的探空观测资料分析得出,季风爆发前海洋大气边界层存在规则的日变化,在中午达到深厚。季风爆发后南海北部大气边界层日变化消失,南海南部依然明显。分析表明对其日变化起重要影响的是短波辐射;潜热输送对大气边界层高度日变化影响不大。与大气边界层厚度日变化相对应,南海南部边界层内水汽日变化明显,而南海北部较不明显。
Diurnal behavior of the marine atmospheric boundary layer （MABL） over the South China Sea （SCS） is not well known, due in part to the lack of direct observations. Based on the GPS sounding datasets obtained four times daily by R/V ＂Kexue 1＂ and R/V ＂Shiyan 3＂ during May-June, 1998 in the SCS, the authors analyze the variations of the MABL height associated with the South China Sea Summer Monsoon （SCSSM） phase. The MABL height in this paper is defined as the lowest level where virtual potential temperature （θv） increases by 1 K from that at the sea surface. The MABL height displays a significant diurnal cycle over the entire SCS before the SCSSM onset. The diurnal cycle remains over the southern SCS even after the monsoon onset, while that over the northern SCS tends to disappear. The MABL develops to its maximum height in the afternoon, suggesting solar radiation plays a crucial role. The latent-heat flux supplies water vapor that promotes the development of the MABL, but it has less effect on the diurnal cycle of the MABL height.
出处
《热带海洋学报》
CAS
CSCD
北大核心
2009年第2期31-35,共5页
Journal of Tropical Oceanography
基金
广东省联合基金项目(U0733002)
国家973项目(2006CB403604)
关键词
南海
季风爆发
大气边界层
日变化
South China Sea
monsoon onset
marine atmospheric boundary layer
diurnal cycle
