The role of forests in global climate adaptation

Forests play a crucial role in regulating the global climate. Yet, forests also influence the local climate conditions through biophysical processes that directly impact human wellbeing. With growing policy emphasis on these climate adaptation effects, we review the scale dependent impacts of forests on climate conditions and their implications for human wellbeing. Generally, existing forests buffer local temperatures, with warming effects in cold regions and cooling effects in hot regions. At a global scale, trees are more conducive to cooling in regions where dense forests would naturally exist. Additionally, forests generally reduce water runoff, which can reduce flooding in wet areas, but it can also limit water availability downstream, especially in drier regions. Together, these findings suggest that climate positive tree effects tend to be most frequent in regions where forests naturally occur, and highlight the growing consensus around the importance of natural forests for climate adaptation.