2012年南海夏季风活跃期与非活跃期广东电白地区海陆大气边界层特征分析  

ANALYSIS OF THE CHARACTERISTICS OF THE LAND-SEA BOUNDARY LAYER OVER THE DIANBAI AREA DURING THE ACTIVE AND INACTIVE PERIODS OF SOUTH CHINA SEA SUMMER MONSOON IN 2012

作　　者：刘潇[1] 王成刚[1] 黄辉军[2] 

机构地区：[1]南京信息工程大学大气物理系,江苏南京210044 [2]中国气象局广州热带海洋气象研究所/广东省区域数值天气预报重点实验室/海洋气象联合开放实验室,广东广州510640

出　　处：《热带气象学报》2017年第1期93-103,共11页Journal of Tropical Meteorology

基　　金：国家自然科学基金项目(41175013);教育部留学回国人员科研启动基金资助项目共同资助

摘　　要：利用2012年6—9月南海夏季风期间的近海海洋气象观测平台(海上平台站)和电白国家气候观象台(电白站)的地面气象站资料,气象塔资料以及GPS探空资料对海上平台站和电白站两站在季风活跃期和非活跃期的大气边界层结构特征进行研究分析。结果表明,活跃期与非活跃期两地的大气边界层结构特征有明显差异。(1)在活跃期两站近地层风向全天由东南风主导,风速较大,且两站均出现连续降水,受云系和降水的影响,与非活跃期相比,电白站近地层日平均气温降低约为2℃;非活跃期两站风向全天无规则变化,且风速值小。(2)在活跃期大气边界层内风向均为一致的东南风,风速较大,200 m以上的风速均大于8 m/s,而在非活跃期大气边界层内风速较小,风向变化较大,同一时刻不同高度的风向差可达180°。(3)在季风非活跃期混合层高度最高可达937 m,而在活跃期,受降水和云系的影响混合层高度明显降低,最大高度仅为700 m左右。(4)活跃期受连续降水影响,大部分时刻的大气边界层内相对湿度大于80%。由此可见在季风活跃期与非活跃期不仅海陆气能量交换发生变化,大气边界层结构特征也有显著变化。The characteristics of the land-sea atmospheric boundary layer during the active and inactive periods of the South China Sea Summer Monsoon （SCSSM） are analyzed by using the observation data obtained from the Dianbai meteorological station and the Marine Meteorological Science Experiment Base at Bohe from June to September in 2012. It is found that the structure of the atmospheric boundary layer in the active and inactive periods of SCSSM differs significantly not only above the land but also over the sea. （1） In the active period, A southeast wind dominates during the whole day, which is observed at both the sea and land sites, and the wind speed is relatively high. In contrast, the wind direction in the inactive period changes irregularly, and the wind speed is smaller than that in the active period. Moreover, in the active period, continuous precipitation is observed. As a result, the average daily temperature in the active period within the surface layer over land is reduced by approximately 2 ℃ than that in the inactive period; （2） Based on the sounding data, during the active period, a prevailing southeast wind exists in the boundary layer, and the wind speed of larger than 8 rn/s persists above the altitude of 200 m. However, during the inactive period, the wind speed is relatively small, and the wind direction changes frequently. The deviation of the wind direction between the upper and lower layers of the boundary layer reaches up to 180 degrees in the inactive period. The temporal behavior of the potential temperature vertical profile in the land-type boundary layer is also analyzed. It is shown that the boundary layer height reaches the maximum of 937 m in the inactive period. In contrast, due to the existence of the precipitation and the clouds during the active period the height of the mixing layer decreases heavily. The highest boundary layer found in the active period has the thickness of only about 700m. The sounding data also shows that the relative humidity in the boundary layer du

关 键 词：南海夏季风 活跃期 非活跃期 大气边界层 海陆差异 

分 类 号：P425.42[天文地球—大气科学及气象学]