Analysis of Quasi-Geostrophic Forcing during the AIMCS (Airborne Investigations of Mesoscale Convective System) Project. Volume 1. Discussion

摘要

Hoskins' Q-vector formulation of geostrophic forcing is applied to diagnose twice-daily soundings from National Weather Service stations during the Airborne Investigations of Mesoscale Convective Systems Project, which took place from 14 June to 16 July 1984. Vector Q represents the time rate of change of an acceleration per unit depth of air parcels. Layer-averaged divergence of Q is related to large-scale vertical motion in a manner analogous to kinematic divergence of wind. Additional diagnostic factors computed include stability tendency and geostrophic frontogenesis function. Large convective systems are accompanied by significant large-scale forcing; absence of significant forcing generally indicates either no convection or convection organized on smaller scales.