The Effect of Different Implementations of the Weak Temperature Gradient
Approximation in Cloud Resolving Models
Abstract
The Weak Temperature Gradient (WTG) approximation has been a popular method for coupling convection in limited-area domain simulations to the large-scale dynamics. However, several different schemes have been created to implement this approximation, and these different WTG schemes show a wide range of different results in an idealized framework. Further investigation shows that different model behavior is caused by the treatment of the different baroclinic modes by the different WTG schemes. More specifically, we hypothesize that the relative strengths of the baroclinic modes plays a large role in these differences, and show that modifying these schemes such that they treat the baroclinic modes in a similar manner accounts for many of the significant differences observed.Abstract content goes here