摘要
本文利用南京北郊164米气象塔实测资料对一次非降水弱冷锋过程的边界层风场结构一三维风速、横锋向水平散度、湍流通量和能量的时空分布，以及多尺度时空分布进行了计算分析。结果表明，在冷暖空气的过渡区（锋区）风场各参量具有明显的梯度，锋区前线的强上升气流与强冷锋相近，但锋区宽度较强冷锋宽得多，其时间尺度为30分钟，水平距离为35公里。锋面过境对风温场的影响时段为24小时，在这期间，出现阵风浪涌和多种中、小尺度（时间尺度为3－4小时、1－20分钟）的湍涡活动。
In this paper, the data gathered from a 164m meteorological tower at the northern sub-urb of Nanjing are used to estimate and analyze the time-space distributions of 3-D wind ve-locity, horizontal cross-front divergence, turbulent flux and energy as well as multi-scale fora dry cold front in boundary layer atmosphere. Results show that significant horizontalgradient of all parameters was concentrated within a transient region (i. e. front zone ), withapproximate 30-minute period or a 35 km horizontal distance, which is wider than those ofstrong cold fronts, but the strong updraft at its leading edge is comparable to those of them.The frontal passage influences wind and temperature field over a period of 24 hours, in whichgust surges and various meso- and micro-scale eddies with time scales of 3-4 hours and 1-20 minutes occur.
出处
《气象科学》
CSCD
北大核心
1996年第4期368-377,共10页
Journal of the Meteorological Sciences
基金
国家自然科学基金!49375230
关键词
冷锋
风场
结构
尺度分析
边界层
cold front
wind-field structure
correlation
turbulent scale
