黄东海大气边界层高度时空变化特征

Temporal and Spatial Variation of Atmospheric Boundary Layer Height(ABLH) over the Yellow-East China Sea

根据2006—2007年大连、青岛和台州逐日高分辨率L波段二次测风雷达探空资料、地面观测资料以及再分析资料,采用干绝热法和位温梯度法分别计算了各个台站的边界层高度,继而分析了黄东海边界层高度多时间尺度变化规律和空间演变特征。结果表明:(1)用清晨探空资料计算每日边界层高度,干绝热法比位温梯度法更为合理可靠;(2)沿海台站边界层高度有显著季节变化,夏季最低,秋季最高,这有别于陆地边界层普遍存在的夏季高、秋冬季节低的季节变化;(3)通过小波分析,发现边界层高度有显著的2～4d天气尺度振荡和10～20d准双周振荡;(4)黄东海上空海洋大气边界层在时间尺度上同样存在着明显的春夏季节低、秋冬季节高的季节变化特征,大部分海区空间上呈现西北低、东南高的分布形态。

Based on the daily high resolution L-band radar soundings, surface observations, and reanalysis data from 2006 to 2007, the atmospheric boundary layer （ABL） heights are calculated by means of the dry adiabatic method （DAM） and the potential temperature gradient method （TGM） over the Yellow-East China Sea. The multi-time-scale variations and spatial distribution characteristics the ABL heights are analyzed. The results are as follows. （1） DAM is more reasonable and reliable compared with TGM to calculate the ABL height with morning soundings. （2） The ABL heights at three coastal stations have pro- nounced seasonal variations, higher in fall and lower in summer. That is different from their inland coun- terparts which are higher in summer and lower in fall and winter. （3） The variations of the ABL heights are periodical with 2-4 d of synoptic scale and quasi-two-week oscillation from wavelet analyses, （4） The ABLover the Yellow-East China Sea is higher in the eastern and southern parts and lower in the western and northern areas.