Work

Are Parameterized Entrainment Rates as Scale‐Dependent as Those Estimated From Cloud Resolving Model Simulations?

Year: 2024

Type: article

Abstract: Entrainment rates at varying horizontal grid spacing were diagnosed and analyzed based on Large Eddy Model (LES) and Cloud Resolving Model (CRM) simulations of shallow and deep convection. Results show the estimated entrainment rates increase with increasing resolution, and the growth rate is roughly power‐law related to resolution. However, all commonly used parameterizations except for the buoyancy sorting scheme fail to reproduce the monotonic increase of entrainment with resolution, but rather a slight decrease instead. For these schemes, it is suggested the power‐law fitting formula derived from LES/CRM simulations can be used as a scaling function for high‐resolution entrainment correction. Preliminary tests show that the application of entrainment scaling largely reduces the parcel buoyancy and thus the convective available potential energy, favoring the reduction of parameterized convection at high resolution.

Source: Geophysical Research Letters

DOI: 10.1029/2024gl110735

Authors: Yaxin Zhao, Xiaocong Wang, Yimin Liu, Guoxiong Wu

Institutions: Chinese Academy of Sciences, Institute of Atmospheric Physics, University of Chinese Academy of Sciences, State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics

Language: English

Topic: Meteorological Phenomena and Simulations

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,900

Funders: National Natural Science Foundation of China, EarthLab, University of Washington