黄海夏季海雾的边界层结构特征及其与春季海雾的对比  

Structure Characteristics of the Yellow Sea Summer Fog in the Boundary Layer and the Comparison with Spring Fog

作　　者：任兆鹏[1,2] 张苏平[1] 

机构地区：[1]中国海洋大学物理海洋教育部重点实验室海洋-大气相互作用与气候实验室,山东青岛266100 [2]青岛市气象局,山东青岛266003

出　　处：《中国海洋大学学报（自然科学版）》2011年第5期23-30,109,共9页Periodical of Ocean University of China

基　　金：国家自然科学基金项目(40975003);中国气象局公益性专项(GYHY200706031);教育部博士点专项基金项目(20090132110008)资助

摘　　要：利用海上浮标站、高分辨率数字式探空仪等多种观测手段和三维中尺度模式，对2008年7月7-11日1次夏季黄海海雾过程的边界层结构特征进行了观测分析与数值模拟，并将结果与春季的黄海海雾个例进行对比。结果表明：（1）夏季海洋大气边界层（MABI，）中无强逆温层，静力稳定度较春季下降，有利于湍流的发展。加之水汽量较大，容易形成比较厚的雾（500m）；春季低空有明显逆温层，水汽供应量较少，但强稳定的层结可以使水汽局限于比较低的空中，形成比较薄的雾层（200m）。（2）在夏季风控制下，青岛近海海洋大气边界层（MABL）中高、低层气块均来自海洋上空，温湿属性差异不大，使得温度垂直差异较小；春季MABL中高、低层气块分别来自陆地和海洋，来自陆地的暖、干气流和海洋的冷却效应导致强逆温层和雾区上方干层的出现。（3）夏季海雾的含水量大，水汽在凝结成雾的过程中放出更多的凝结潜热，雾中的海表面气温（SAT）明显高于海表面水温（SST）；春季雾顶强烈的长波辐射冷却和湍流混合使雾中气温明显下降，雾中SAT与SST更加接近，甚至出现SAT小于SST。以上结果有助于对海雾形成机制的认识。A summer sea fog event occurred over the Yellow Sea on 7~11 July, 2008 is investigated in this paper through various observational data and a three dimensional mesoscale model WRF. Comparing with a spring sea fog event, it concluded that （1） there is not obvious inversion layer in the marine atmos- phere boundary layer in summer. The weaker stability is possibly in favor of development of turbulence in the condition of high water vapor content. Sea fog forms through the water vapor transport upward. While lower sea fog form in spring as the result of obvious inversion layer and low water vapor content which keep the water vapor in low level. （2） Weak stability and less vertical temperature differences formed as the result of both of high and low level air mass come from sea in the control of summer wind which are similar in temperature and humidity. Strong inversion and dry level form as the result of warm dry air mass and cooling effect of sea, because high and low level air mass come from land and sea respectively. （3） More condensation latent heat release in the condition of high water vapor content in summer sea fog which induces surface air temperature （SAT） much higher than sea surface temperature （SST）. Strong long wave radiation at the top of sea fog and turbulence in fog induce air temperature decreasing rapidly. SAT is much close even less than SST. This result is helpful to understand of sea fog formation mechanism and forecasting.

关 键 词：海雾 海洋大气边界层 结构特征 对比 

分 类 号：P426.4[天文地球—大气科学及气象学]