C‐POOL: A scheme for modelling convective cold pools in the Met Office Unified Model. (10th January 2022)

• Record Type: Journal Article
• Authors: Rooney, Gabriel G.; Stirling, Alison J.; Stratton, Rachel A.; Whitall, Michael
• Is Part Of: Quarterly journal of the Royal Meteorological Society. Volume 148:Number 743(2022)
• Page Start: 962
• Page End: 980
• Publication Date: 2022-01-10
• Subjects: cold pools -- diurnal cycle -- parametrized convection -- tropical rainfall; Meteorology -- Periodicals; 551.5
• DOI: 10.1002/qj.4241
• Languages: English
• ISSNs: 0035-9009

Abstract

Abstract: A new parametrization scheme representing the lifecycle and effects of convective cold pools (C‐POOL) is presented. The scheme comprises a column‐crossing prognostic model of the initiation by downdraughts, interaction and decay of cold pools, based upon approximations taken from similarity modelling of gravity currents. The prognostic variables are drawn upon to feed back into the convection parametrization scheme. These feedbacks affect the convective diagnosis, initiation from the boundary layer, parcel ascent and entrainment. Tests of the model show that it improves representation of the diurnal cycle of tropical rainfall, previously well‐known as a weakness of parametrized convection. Abstract : A new parametrization of the lifecycle and effects of convective cold pools (C‐POOL) in the Met Office Unified Model is presented. The scheme comprises a column‐crossing prognostic model of the initiation by downdraughts, interaction and decay of cold pools, based upon similarity modelling of gravity currents. The parametrization feeds cold‐pool effects back into the convection parametrization scheme, modifying the diurnal evolution of convection. Initial testing shows improvement in the diurnal cycle of tropical rainfall in the global climate model.