ICON-Sapphire: simulating the components of the Earth System and their interactions at kilometer and subkilometer scales

Abstract

Abstract. State-of-the-art Earth System models typically employ grid spacings of O(100 km), too coarse to explicitly resolve main drivers of the flow of energy and matter across the Earth System. In this paper, we present the new ICON-Sapphire model configuration, which targets a representation of the components of the Earth System and their interactions with a grid spacing of 10 km and finer. Through the use of selected simulation examples, we demonstrate that ICON-Sapphire can already now (i) be run coupled globally on seasonal time scales with a grid spacing of 5 km and on monthly time scales with a grid spacing of 2.5 km, (ii) resolve large eddies in the atmosphere using hectometer grid spacings on limited-area domains in atmosphere-only simulations, (iii) resolve submesoscale ocean eddies by using a global uniform grid of 1.25 km or a telescoping grid with a finest grid spacing of 530 m, the latter coupled to a uniform atmosphere and (iv) simulate biogeochemistry in an ocean-only simulation integrated for 4 years at 10 km. Comparison to observations of these various configurations reveals no obvious pitfall. The throughput of the coupled 5-km global simulation is 126 simulated days per day employing 21 % of the latest machine of the German Climate Computing Center. Extrapolating from these results, multi-decadal global simulations including interactive carbon are now possible and short global simulations resolving large eddies in the atmosphere and submesoscale eddies in the ocean are within reach.

Learning by Doing: Seasonal and Diurnal Features of Tropical Precipitation in a Global‐Coupled Storm‐Resolving Model

“…These issues motivate the present study, which analyzes the behavior of the coupled system when allowing for an explicit, albeit coarse, representation of meso‐beta scale processes for an entire annual cycle. The simulations are performed using the ICOsahedral Nonhydrostatic (ICON) model with a horizontal grid spacing of 5 km across all components (Hohenegger et al., 2022). These are, to our knowledge, the first simulations of their kind, also meaning that the model system is still in an early stage of its development, leading to a greater potential for errors and imbalances.…”

Improving scalability of Earth system models through coarse-grained component concurrency – a case study with the ICON v2.6.5 modelling system

“…A positive side effect of coarse-grained component concurrency is that it naturally bequeaths concurrency to the infrastructure attached to these components, like I/O and realtime post-processing. In particular, I/O can pose a significant performance bottleneck, and parallel asynchronous I/O approaches have already been developed; see, for example, Brown et al (2020), Yepes-Arbós et al (2022), and Hohenegger et al (2022. The naturally inherited concurrency to the components' infrastructure can further enhance the performance of such schemes.…”

“…ICON is an Earth system model framework developed in collaboration with the German Weather Service (DWD), the Max Planck Institute for Meteorology (MPIM), the Institute of Meteorology and Climate Research at the Karlsruhe Institute of Technology, and the German Climate Computing Centre (DKRZ). It consists of the numerical weather prediction model ICON-NWP (Zängl et al, 2015), the climate atmosphere model ICON-A (Giorgetta et al, 2018;Crueger et al, 2018), the land model JSBACH (Nabel et al, 2020), the ocean model ICON-O (Korn et al, 2022), the atmosphere aerosol and chemistry model ICON-ART (Rieger et al, 2015), and the marine biogeochemistry model HAMOCC (Ilyina et al, 2013). The ICON Earth system model ICON-ESM consists of ICON-A, JSBACH, ICON-O, and HAMOCC (Jungclaus et al, 2022).…”

“…It consists of the numerical weather prediction model ICON-NWP (Zängl et al, 2015), the climate atmosphere model ICON-A (Giorgetta et al, 2018;Crueger et al, 2018), the land model JSBACH (Nabel et al, 2020), the ocean model ICON-O (Korn et al, 2022), the atmosphere aerosol and chemistry model ICON-ART (Rieger et al, 2015), and the marine biogeochemistry model HAMOCC (Ilyina et al, 2013). The ICON Earth system model ICON-ESM consists of ICON-A, JSBACH, ICON-O, and HAMOCC (Jungclaus et al, 2022).…”

“…1 left. In non-uniform setups, it has been tested with "telescoping" setups (Korn et al, 2022), which can produce local grid spacings of 600 m (Hohenegger et al, 2022). Furthermore, a topographic and coastal adaptive local refinement (Logemann et al, 2021) has been used for global coastal ocean simulations (see Fig.…”