Observational Study on Atmospheric and Oceanic Boundary-Layer Structures Accompanying the Okhotsk Anticyclone under Fog and Non-Fog Conditions
Observational Study on Atmospheric and Oceanic Boundary-Layer Structures Accompanying the Okhotsk Anticyclone under Fog and Non-Fog Conditions
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DOI：
10.2151/jmsj.86.753
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发表时间：
2008-10
影响因子：
3.1
通讯作者：
Y. Tachibana;K. Iwamoto;H. Ogawa;M. Shiohara;K. Takeuchi;M. Wakatsuchi
中科院分区：
文献类型：
--
作者：
Y. Tachibana;K. Iwamoto;H. Ogawa;M. Shiohara;K. Takeuchi;M. Wakatsuchi
1998年7月首次在鄂霍次克海进行了一系列GPS无线电探空和海洋观测。观测期间，在鄂霍次克海上空普遍存在的反气旋作用下，观测到雾期和非雾期大气和海洋边界层结构存在明显差异。在雾期，观测到的强地面风和向上的感热通量促进了大气和海洋的垂直混合。混合良好的海洋边界层高度在大气中为200 ~ 1000m，在海洋中为10 ~ 15m。当地面空气温度（SAT）低于下垫海表温度（SST）时，雾就会形成。通过对观测到的混合良好的大气边界层在雾期的轨迹分析，边界层气团经过暖（冷）海温后倾向于形成层状（层积云状）雾。在无雾期，由于地面风弱和感热通量下降，大气和海洋边界层分层稳定。在无雾期，无论气团轨迹如何，SAT都比海温偏暖。
A series of GPS radiosonde and oceanic observations was conducted over the Okhotsk Sea for the first time in July 1998. Under the prevalent anticyclone over the Okhotsk Sea during the observations, distinct differences in the atmospheric and oceanic boundary-layer structure were observed between the fog and non-fog periods. During the fog period, the observed strong surface winds and upward sensible heat fluxes promoted vertical mixing in the atmosphere and ocean. The height of the well-mixed marine boundary layer varied from 200 to 1000m in the atmosphere, and 10 to 15 m in the ocean, respectively. The fog formation occurred when surface air temperature (SAT) was cooler than the underlying sea surface temperature (SST). By trajectory analyses for the observed well-mixed atmospheric boundary layer during the fog period, the boundary-layer air mass that has passed over warm (cool) SST tended to form stratus-like (stratocumulus-like) fog. In the non-fog period, by contrast, atmospheric and oceanic boundary layers were stably stratified due to weak surface winds and downward sensible heat fluxes. Regardless of the air mass trajectory, SAT is warmer than underlying SST during the no-fog period.