A Second-Order Closure Turbulence Model: New Heat Flux Equations and No Critical Richardson Number

• DOI: 10.1175/jas-d-19-0240.1
• Publication Date: 2020-07-21T18:45:41Z
• Authors: Y. Cheng; V. M. Canuto; A. M. Howard; A. S. Ackerman; M. Kelley; A. M. Fridlind; G. A. Schmidt; M. S. Yao; A. Del Genio; G. S. Elsaesser
• Keywords: Richardson number; Closure (psychology)

Abstract We formulate a new second-order closure turbulence model by employing recent for the pressure–temperature correlation at equation level. As result, we obtain heat flux equations that avoid long-standing issue of finite critical Richardson number. The new, structurally simpler improves on Mellor–Yamada and Galperin et al. models; key feature includes enhanced mixing under stable conditions facilitating agreement with observational, experimental, high-resolution numerical datasets. predicts planetary boundary layer height deeper than predicted models low numbers, as demonstrated in single-column runs GISS ModelE general circulation model.