南黄海海气热通量观测及其与OAflux数据集比较研究

Observations of Air-sea Heat Flux in the South Yellow Sea and Their Comparison With OAflux Dataset

2007年在南黄海进行了3个航次的热通量观测,包括长、短波辐射,近海表空气温度、湿度,风速,海表皮温等观测数据。依据计算的冬季、春季、秋季三个航次的海气热通量分析了热通量不同季节特征,南黄海海域冬季、春季和秋季平均潜热通量分别为80.7W/m2,5.6W/m2和142.1W/m2,感热通量分别为32.0W/m2,-12.5W/m2和18.9W/m2(海洋向大气传递为正)。将国际较为通用的OAflux数据集与3个季节观测数据做了逐点的比对,作为对OAflux数据集在南黄海海域的评估,结果显示:OAflux数据集热通量结果与观测数据在2006—2007年冬季最为接近,感热和潜热通量均方差是15.3W/m2和21.4W/m2。春季的潜热通量存在明显偏差,均方差为28.4W/m2。秋季的感热和潜热通量均存在显著偏差,均方差分别为20.5W/m2和57.5W/m2。导致春季偏差的主要原因是OAflux数据集和现场观测的近海表空气湿度差异,而秋季偏差则应主要归因于海表温度的偏差。

Three comprehensive cruises were conducted in the South Yellow Sea in 2007 to investigate the radiation and flux-related meteorological and oceanic data including air temperature, humidity, wind speed and SST etc. Both the sensible and the latent heat fluxes were calculated and the seasonal characteristics of air-sea heat flux were analyzed. The results show that the averaged latent heat flux in the South Yellow Sea is 80.7 W/m2 , 5.6 W/m2 and 142.1 W/m2 in winter, spring and autumn, respectively and the sensible one is 32.0 W/m2 , -12.5 W/m2 and 18.9 W/m2 , respectively. The air-sea heat flux data observed in the three cruises are compared to the OAflux dataset. It is found that the OAflux dataset fit well with the data observed in winter in 2006--2007, with a mean square deviation being 15.3 W/m2 for the sensible heat flux and 21.4 W/m2 for the latent one, but there are obvious differences in the latent heat flux in spring （the mean square deviation being 28.4 W/m2） and in both the sensible and the latent heat fluxes in autumn （the mean square deviation being 20.5 W/m2 and 57.5 W/m2 respectively）. Further investigation suggests that the air-humidity difference present between the OAflux dataset and the data observed in the cruises could be responsible for the difference in the latent heat flux in spring in 2007, whereas the differences in heat fluxes in autumn are mainly attributed to the difference in SST.