https://en.wikipedia.org/wiki/Climate_model

Cloud-resolving climate models are nowadays run on high intensity super-computers which have a high power consumption and thus cause CO2 emissions.[44] They require exascale computing [..]. For example, the Frontier exascale supercomputer consumes 29 MW.[45] It can simulate a year’s worth of climate at cloud resolving scales in a day.[46]

Techniques that could lead to energy savings, include for example: "reducing floating point precision computation; developing machine learning algorithms to avoid unnecessary computations; and creating a new generation of scalable numerical algorithms that would enable higher throughput in terms of simulated years per wall clock day."[44]