Cyclonic and anticyclonic development

✍ Scribed by R. C. Sutcliffe

• Book ID: 104570125
• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 436 KB
• Volume: 65
• Category: Article
• ISSN: 0035-9009
• DOI: 10.1002/qj.49706528208

✦ Synopsis

Abstract

Development of pressure systems involves horizontal divergence (positive or negative) approximately balanced by divergence of opposite sign in the upper troposphere, the total divergence integrated vertically and represented by the rate of change of surface pressure being a relatively small residual. It follows that a criterion for development is that there should be a significant difference between the lower and upper fields of divergence. Divergence is determined by the field of geostrophic departure or acceleration and it is shown that the difference between lower and upper divergence consists of two parts due respectively to shearing and to the development of thermal gradients. Rules concerning the distribution of surface divergence and convergence in different pressure and temperature distributions are inferred and a method of approaching the problem of forecasting on a three‐dimensional basis is put forward.