New study shows highly different responses of surface vs air temperature following deforestation

Deforestation influences the exchange of moisture and heat between the land surface and the atmosphere (the so-called biogeophysical effect). This, in turn, can alter temperature. It is important whether deforestation influences the temperature at the surface, the air temperature, or the temperature higher up in the atmosphere because these different heights matter for living conditions of humans and other organisms in different ways. However, many studies that focus on the biogeophysical deforestation effects tend to use these different temperature measure interchangeably and report just one or the other. In this new study, the authors use simulations with a climate model to investigate the response of both surface and air temperature and compare its strength. They do so separately for temperature changes at the location of deforestation (‘local effects’), and elsewhere (‘nonlocal effects’).

The authors find that while nonlocal effects influence surface and air temperature similarly, the local effects generally influence surface temperature more strongly than atmospheric temperature, especially for daily maximum temperatures. The authors compare results across different climate models, and show that both for summer warming and winter cooling the surface temperature change exceeds the air temperature change locally by a factor of two. This study clearly highlights that temperature definition is important, when investigating the temperature effects of deforestation.