Limiting planetary warming requires reducing emissions of carbon dioxide, and even removing carbon dioxide to lower the atmospheric concentration. Principal among the climate services of forests is their carbon storage. This is the basis upon which forest advocates call to protect, restore, and manage forests to mitigate the harmful effects of climate change. Large areas of new forests must be planted to offset anthropogenic carbon dioxide emissions. Yet the climate services of forests extend beyond just carbon. Forests influence climate through many biogeophysical and biogeochemical mechanisms, often in ways that augment the carbon benefits and sometimes to the contrary. To the carbon benefits of forests must be added their influence on temperature and precipitation through albedo, surface roughness, evapotranspiration, and biogenic aerosols. If the potential of forests to lessen planetary warming over the coming century is to be realized, their many influences on climate must be synthesized into an integrated understanding. In this, tropical forests are readily recognized as beneficial for climate.