Welcome to Chinese Agricultural Science Bulletin,

Chinese Agricultural Science Bulletin ›› 2015, Vol. 31 ›› Issue (20): 224-232.doi: 10.11924/j.issn.1000-6850.casb14120195

Special Issue: 农业气象

Previous Articles     Next Articles

Analysis of Two Cold Wave Processes with Gale and Snow in Inner Mongolia in the Spring 2014

Ma Suyan1, Han Jingwei1, Song Guiying1, Shi Jinli2   

  1. (1Inner Mongolian Meteorological Observatory, Hohhot 010051; 2Meteorological Sciences Institute of Inner Mongolia, Hohhot 010051)
  • Received:2014-12-29 Revised:2015-06-30 Accepted:2015-04-24 Online:2015-07-28 Published:2015-07-28

Abstract: The cold wave process with similar circulation characteristics have similar outburst pattern, climate and range of influence, but there are also unique characteristics for individual cold wave process and the difference can result in the wrong judgment in forecast. In this special case, based on routine observation, automatic meteorological observing station and NCEP 1°×1° 6 h interval reanalyzed data, two cold waves occurred in April 24 (process 1) and May 1 (process 2) in 2014 in Inner Mongolia were comparatively analyzed on circulation situation, system, thermodynamic and the dynamic mechanism of the cold wave outburst, utilizing synoptic and diagnostic analyses method. The results are as follows: in middle and high altitudes of northern hemisphere, the circulation patterns of the two cold waves showed ‘one trough and tow ridge’ at 500 hPa. Based on the temperature rising strongly in prior period of the two cold waves, the average temperatures were 1.0-7.3 and 0.1-10.7℃ higher than the same period. The cold trough and strong frontal zone at 500 hPa were accumulated in the north of Xinjiang, and the cold wave broke out and invaded to the south. There were discrepancies between the burst and cause of the two cold waves: process 1 belonged to the revising of the transverse trough, and the trough was strengthened to vortex meanwhile moved to southeast because of evacuation structures and the positive vorticity advection before the trough, when the cold advection center moved to the front of the trough, transverse trough was revised and the cold wave broke out. Process 2 belonged to the small trough moving eastward, and the cold trough deepened after moving across the Altai Mountains and Mongolia plateau, finally the cold air invaded to Inner Mongolia and the cold wave broke out. Although strong cooling borough-wide was caused by the two cold waves, the gale, sandstorm and precipitation showed different characteristics because of the different influence ways and causes. The gale and sandstorm were correlated with not only the cold advection but also when and where the momentum disseminated. In terms of the precipitation of the two cold waves, the characteristics of water vapor transport and temperature stratification in the low layer were favorable to precipitation and precipitation transformation. Focusing on the burst and dynamic process of the similar cold waves was good for the forecasting of cooling, gale, sandstorm and precipitation.