A Study on the Trajectories of Mesoscale Convective Systems and Their Environmental Physical Field Values Using GMS Image

Abstract

The forecasting of disaster weather, especially intensive convective weather, is becoming increasingly important. Recent evidence has indicated that the intensive precipitation in the Changjiang River Basin and the south-west region of China is closely related to the activity of Mesoscale Convective Systems (MCS), which move out of the Tibetan Plateau in China. To date, however, the mechanism of MCS and their structure are not yet clear, due to restrictions on time and space scales in traditional observation data, especially in the Tibetan Plateau. To reveal MCS features and trajectories, in this paper, MCS are automatically tracked over the Tibetan Plateau using Geostationary Meteorological Satellite (GMS) infrared black-body temperature (Tbb) data from June to August 1998. Based on these, spatial clustering analysis is applied to study the relationships between the trajectories of MCS over the Tibetan Plateau and their environmental physical field values. And, the spatial distribution features of environmental physical field of influencing MCS move out of the Plateau are obtained. Consequently, these prove new methods to discover the regulations of MCS trajectories and the causes of MCS origination and development. Meanwhile, the results show that it is of great value in improving the precision of heavy rainfall and intensive convective weather forecasting in the Changjiang River Basin and the south-west region of China.