“New weather models don’t have any physics built in. They work in a way similar to the text-generation technology at the heart of ChatGPT. In that case, the machine-learning algorithms are not told rules of grammar or syntax, but they become able to mimic them after digesting enough data to learn patterns of usage. Similarly, the new weather forecasting models learn the patterns from decades of physical atmospheric data collected in an ECMWF data set called ERA5.”

From Ars Technica.