In most climate model projections for the 21st century with moderate to high fossil fuel emissions, the Amazon becomes drier and Indonesia becomes wetter. Within the climate modeling community, this pattern of diverging tropical land precipitation had been attributed to the radiative effects of atmospheric carbon dioxide that influences ocean temperatures and atmospheric circulation. In a new analysis published in Nature Climate Change, Kooperman et al. show that the direct effect of rising carbon dioxide on tropical forests is responsible for much of this pattern. In response to rising CO2, plant stomates close, causing more absorbed radiation to dissipate in the form of sensible heat and less in the form of latent heat. In the Amazon, these changes in the surface energy budget suppress precipitation across lowland forests within the models, allowing more moisture contained in the tropical jet flowing from the Atlantic to reach the Andes. In Indonesia, greater sensible heating on land triggers a stronger land-sea breeze and moisture convergence over the islands of Sumatra and Borneo. This work suggests neotropical forests may be more vulnerable to climate warming, as they will have less available soil moisture to evaporatively cool. Higher levels of rainfall in Indonesia may make it easier to conserve tropical peatlands, but other important land management steps must be undertaken, including restoration work to remove canal networks.