E3.4 E3SM-FIVE, Progress and Plan

The Framework for Improvement by Vertical Enhancement (FIVE) has been proposed as a promising approach to improve the representation of shallow clouds in the Energy Exascale Earth System Model (E3SM). FIVE consists of the computation of vertically enhanced physics (VEP) on high resolution vertical grids and the exchange of tendencies between the host model and VEP. To achieve a balance between improved model performance and computational cost, this project will not only implement FIVE into E3SM but also develop an adaptive vertical grid (AVG) method, in which vertical resolution and timestep for VEP adapt to the atmospheric state. Progress and plans for the project will be discussed in this presentation, especially for AVG development. AVG requires a method for resolution criteria, which requires an a priori estimate of the error in the simulation with standard E3SM configuration (i.e., no enhancement) compared to that with enhanced vertical resolution and timestep. As a first step, representation of shallow clouds simulated with the E3SM single column model is examined for a series of cases (BOMEX, DYCOMS-II RF01, RF02, and RICO) for standard E3SM configurations and then with enhanced vertical resolutions and timesteps. Sensitivities to vertical resolution and timestep are studied for the CLUBB parameters tuned for E3SM and their default values. Other material to be discussed includes the current stage of implementation of FIVE into the E3SM SCM, algorithmic consideration for implementing FIVE into E3SM with AVG, and development of a framework to test FIVE at E3SM’s target horizontal resolution of O(10 km).