论文部分内容阅读
2008年4—10月在中国南海西沙永兴岛近海进行了第4次海-气通量观测试验,获得了整个夏季风期间近海面层湍流脉动量及辐射、表层水温、波浪及距水面3.5、7.0、10.5m高度温、湿、风梯度观测资料,根据涡动相关法和COARE3.0法计算结果研究了2008年南海西南季风爆发、发展、中断、衰退包括暴雨、台风、冷空气影响等天气过程中海-气通量交换和热量收支变化。结果表明:(1)季风爆发前的晴天太阳总辐射强,而海洋失热量较小,热量净收支为较大正值,海面温度迅速升高。季风爆发期太阳总辐射仍然较强,大气长波辐射也有所增强,而海面长波辐射变化很小,故海面净辐射收支仍为正值;(2)季风活跃期特别是降水阶段感热通量增大,季风中断阶段变小;季风活跃期虽然潜热通量增大,由于太阳短波辐射没有减少,海洋净热量收支稍有盈余;中断阶段潜热通量、感热通量减少,海洋吸热大于季风活跃期;降水阶段由于太阳短波辐射减小,感热通量增大,海洋热量收支出现较大负值,海面温度很快降低。季风衰退期风力减弱,湿度减小,潜热通量减小,海洋热量收入又出现较大正值,海面温度回升;(3)台风影响过程中潜热通量随着风速增强迅速增大;感热通量因降水情况不同而有差异,晴天时减小,大雨时剧烈增大;由于太阳短波辐射减少、潜热通量剧增,海洋热量净收支出现负值,促使海面温度迅速降低;(4)动量通量主要与海表面风速有关;动量通量τ与风速V的关系可以表示为τ=0.00171v~2-0.003809v+0.02213。
From April to October in 2008, the 4th sea-air flux observation was conducted offshore Yongxing Island, Xisha, South China Sea, and the turbulent pulse and radiation, surface water temperature, wave and surface water from the surface over the whole summer monsoon were obtained. , 7.0, 10.5m high temperature, wet and wind gradient observation data. According to the eddy covariance method and COARE3.0 method, the effects of heavy rain, typhoon and cold air on the onset and development of southwest monsoon in the South China Sea in 2008 were studied. Changes of sea-air flux and heat budget in the course of the weather. The results show that: (1) The sunny solar radiation before the monsoon onset is strong, while the amount of marine heat loss is small, the net heat budget is positive and the sea surface temperature rises rapidly. The total solar radiation in the monsoon period is still strong, the long-wave radiation in the atmosphere is also enhanced, and the change of the long-wave radiation in the sea surface is small, so the net radiation budget of the sea surface is still positive; (2) Increase, the monsoon phase becomes smaller; during the active monsoon period, although the latent heat flux increases, there is a slight surplus of the net ocean heat due to the shortening of the solar shortwave radiation; the latent heat flux and the sensible heat flux decrease in the interruption phase, Which is greater than the active period of the monsoon. During the precipitation stage, due to the decrease of the solar shortwave radiation and the increase of the sensible heat flux, the thermal balance of the oceans and seas has a large negative value, and the sea surface temperature decreases rapidly. During the monsoon recession, the wind weakened, the humidity decreased, the latent heat flux decreased, and the caloric revenue of the ocean appeared a larger positive value and the sea surface temperature rose. (3) The latent heat flux increased rapidly with the increase of the wind speed during the typhoon. Fluxes vary due to different precipitation conditions, decreasing in sunny days and drastically increasing in heavy rains; due to a decrease in solar shortwave radiation and a dramatic increase in latent heat flux, the net heat balance of the ocean is negative, prompting a rapid decrease of sea surface temperature; (4) ) Momentum flux is mainly related to the wind speed at sea surface; the relationship between momentum flux τ and wind velocity V can be expressed as τ = 0.00171v ~ 2-0.003809v + 0.02213.