The 2021 Nobel Prize in Physics was awarded to Syukuro Manabe and Klaus Hasselmann “for the physical modelling of Earth’s climate, quantifying variability and reliably predicting global warming”, and to Giorgio Parisi “for the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales.”
To read about the science behind the prize in more detail, check out the Nobel Prize press release here, or the more detailed scientific background here.