Ai2 has updated its climate-emulation system: ACE generates roughly 100-kilometer outputs, and HiROv2 downscales them to three-kilometer fields. The new version jointly covers rainfall, wind and pressure with improved extreme-event reproduction.
Ai2 provides downloadable models, a technical report, notebooks and a demo of pregenerated outputs. It reports a total cost around one three-hundredth of X-SHiELD, the reference simulation.
This measures reproduction of a simulation, not universal accuracy against weather observations. Trained on X-SHiELD, HiROv2 is tied to the matching ACE configuration. It cannot yet generate high-resolution outputs for historical ERA5 data or warmer future climates; those are planned extensions.
Cheaper simulation ensembles may help extreme-weather research if the source simulator’s assumptions remain visible.