# ACE2-ERA5

Ai2 Climate Emulator (ACE) is a family of models designed to simulate atmospheric variability from the time scale of days to centuries.

**Disclaimer: ACE models are research tools and should not be used for operational climate predictions.**

ACE-climSST is the original `ACE' model, as described in [ACE: A fast, skillful learned global atmospheric model for climate prediction](https://arxiv.org/abs/2310.02074).
It is trained on output from the FV3GFS atmospheric model forced with annually-repeating climatological sea surface temperature.

Code for doing inference with ACE models can be found here: [https://github.com/ai2cm/ace](https://github.com/ai2cm/ace)
with corresponding documentation here: [https://ai2-climate-emulator.readthedocs.io/en/stable/](https://ai2-climate-emulator.readthedocs.io/en/stable/)

Briefly, the strengths of ACE-climSST are:
- long-term stability
- highly accurate time-mean climate compared to its target dataset
- very fast inference compared to typical physics-based atmospheric models

Some known weaknesses are:
- responses to more El Niño-like sea surface temperature and long-term warming trends are not accurately captured
- small but non-zero drifts in total dry air mass of the atmosphere

Refer to [published manuscript](https://arxiv.org/abs/2310.02074) for more details.