Large-eddy simulations with ClimateMachine: a new open-source code for atmospheric simulations on GPUs and CPUs

TL;DR

ClimateMachine is an open-source, performance-portable atmospheric modeling framework in Julia, capable of global and high-resolution LES simulations on CPUs and GPUs, demonstrated through benchmark cases and flow configurations.

Contribution

It introduces a novel, performance-portable atmospheric modeling framework using Julia, supporting both global and high-resolution LES with energy-conserving discretization.

Findings

ClimateMachine performs well on CPUs and GPUs.

It accurately reproduces benchmark cases and atmospheric flows.

The code demonstrates good scaling and conservation properties.

Abstract

We introduce ClimateMachine, a new open-source atmosphere modeling framework using the Julia language to be performance portable on central processing units (CPUs) and graphics processing units (GPUs). ClimateMachine uses a common framework both for coarser-resolution global simulations and for high-resolution, limited-area large-eddy simulations (LES). Here, we demonstrate the LES configuration of the atmosphere model in canonical benchmark cases and atmospheric flows, using an energy-conserving nodal discontinuous-Galerkin (DG) discretization of the governing equations. Resolution dependence, conservation characteristics and scaling metrics are examined in comparison with existing LES codes. They demonstrate the utility of ClimateMachine as a modelling tool for limited-area LES flow configurations.