Source: Geophysical Research Letters
How precipitation changes in response to warming over land is difficult to capture in simple terms. Notably, the “rich-get-richer” paradigm, which predicts that regions get wetter or drier depending on being climatologically wet or dry, does not hold. This is because whether it rains or not depends not only on the atmosphere’s local humidity content, but also on whether the ascending motions that lead to condensation and precipitation are primed by global conditions. While the increase in atmospheric humidity in response to warming is well understood, how atmospheric motions respond is not.
Duan et al.  find that model projections of precipitation change agree when looked at in the space defined by classifying climatological aridity and daily soil moisture into percentile classes. By and large, the occurrence of transitional and wet regimes, where evaporation increases with soil moisture until it saturates, is expected to decrease.
This change is captured in the brown shading in the figure above, representing decreases in rain (lower left), moisture convergence (lower right) and evaporation (upper right). In contrast, the occurrence of a new regime, characterized by decoupling of soil moisture and evaporation, is predicted to increase, in the green regions. Overall, these changes express a redistribution of rain towards more intense events.
Citation: Duan, S. Q., Findell, K. L., & Fueglistaler, S. A. (2023). Coherent mechanistic patterns of tropical land hydroclimate changes. Geophysical Research Letters, 50, e2022GL102285. https://doi.org/10.1029/2022GL102285
—Alessandra Giannini, Editor, Geophysical Research Letters