华南海雾边界层过程的观测研究

In the marine environment, sea fog typically occurs as a result of the warmer maritime air advection over the cooler waters. However, the formation of fog depends on the synoptic situation of the atmosphere, and different physical processes are responsible for their formation and evolution. The study by Taylor (1917) found that the air temperatures in fog ranged from several degrees warmer than that of the sea to 1-2 degrees colder than the sea. Warm fogs tended to occur in warm air advection conditions, while cold fogs tended to occur in light winds. Warm sea fog is the most popular type of fog in the coastal waters China, often with a thick fog layer, and long duration, more the disasters caused. Due to the complexity of the boundary layer conditions and physical processes involved in the warm sea fog, recently it is lack on the mechanism of the warm sea fog. .This proposal is planned to optimize and improve the schemes of field observations based on the completed projects sponsored by the NSFC to obtain more representative and accurate data of the boundary layer vertical structure, turbulent fluxes and marine meteorological elements. On the basis of the observed data, the conventional data analysis technology and a 1D boundary numerical model are used to investigate the key synoptic and boundary layer conditions which the property of cold or warm sea fog is determined by and the key physical processes those results in the vertical development of warm sea fog. The knowledge on the mechanism of warm sea fog development and maintenance will provide a theoretical basis for the sea fog forecasting method, and will also lay a foundation for development of the parameterization scheme of boundary layer in the sea fog numerical models. .The sea fog observation experiment will be carried out at Marine Meteorology Experiment Base at Maoming, Bohe with advanced equipment and reasonable observation planning. The research topic and scientific issues in this proposal project is based on existing research base, and the analytical methods have been identified to be effective. So the proposal project is expected to achieve the original scientific findings.

暖湿气团平流到冷海面上，既可能形成气温比海温高的暖海雾，也可能形成气温比海温低的冷海雾。暖海雾是中国近海最常见的一种雾，往往雾层深厚、持续时间的长、造成的危害大。由于暖海雾边界层条件和物理过程的复杂性，目前国际上对暖海雾的机制还缺乏认识。.本项目拟在已结题国基金项目的基础上，优化和改善外场观测方案，获取具有较好代表性和准确性的边界层垂直结构、湍流通量和海洋气象要素数据；在实测数据的基础上，采用常规数据分析和数值模拟诊断相结合的研究路线，通过对决定冷/暖海雾的天气和边界层条件、导致暖海雾垂直发展的物理过程进行深入的研究，充分认识暖海雾发展和维持的机制，为海雾的预报方法研究提供理论依据，也为发展海雾数值预报模式边界层参数化方案打下基础。观测试验以茂名博贺观测基地为依托，设备先进、观测方案合理。项目拟研究内容和科学问题基于已有研究基础，研究分析方法成熟，有望取得原创性的研究成果。