CAJ | 학술논문

分析2011年2月25—27日张家口市降雪天气过程的高空天气形势，结果表明，降雪期间500 hPa高空在新疆北部是一个深厚的低涡系统，冷低涡不断分裂出小股冷空气东移影响张家口市；850 hPa低涡、暖舌、切变线和低空急流为此次长时间降雪提供了必要条件；26日08：00850 hPa张家口市西部的切变线，是造成降雪的关键性动力系统；25—28日张家口市上空850～700 hPa相对湿度大值区的出现时间与降水时间相吻合，较好的中低层湿度状况为降雪提供了原材料。
분석2011년2월25—27일장가구시강설천기과정적고공천기형세，결과표명，강설기간500 hPa고공재신강북부시일개심후적저와계통，랭저와불단분렬출소고랭공기동이영향장가구시；850 hPa저와、난설、절변선화저공급류위차차장시간강설제공료필요조건；26일08：00850 hPa장가구시서부적절변선，시조성강설적관건성동력계통；25—28일장가구시상공850～700 hPa상대습도대치구적출현시간여강수시간상문합，교호적중저층습도상황위강설제공료원재료。
The high-altitude situation of a snowfall process happened in Zhangjiakou from February 25 to 27, 2011 was analyzed. The results indicated that 500 hPa height fields over the northern Xinjiang was a deep low vortex system, the cold air continuously broke away from low cold vortex and moved east affecting Zhangjiakou. Low vortex at 850 hPa, warm tongue, shear line and low-level jet provided necessary condi-tions for the snowfall. The shear line at 850 hPa over western Zhangjiakou on February 26 at 08:00 am was the key dynamic system that leading to snowfall. The occurrence time of high value area of relative humidity at 850-700 hPa over Zhangjiakou on February 25 -28 was consistent with the precipitation time, good humidity condition at the mid-low-er layer provided main materials for the snowfall.