Forest ecosystems are a large carbon sink because of their ability to absorb carbon dioxide from the atmosphere. They play a huge role in the mitigation of climate change, but the impacts of deforestation has cause the Earth’s surface to heat up. Researchers at the European Commission Joint Research Centre published an article in February of 2018 in the journal Nature Connections detailing how recent changes to the vegetation that covers the earth is causing it to heat up. They examined the effects of cutting down vast expanses of evergreen forests for agricultural expansion on energy imbalances that contribute to the rise in local surface temperatures and global warming overall. These actions have alter radiative and non-radiative properties of the surface.
Using satellite data, the researchers analyzed changes in vegetation cover from 2000 to 2015 all over the world and linked them to changes in the surface energy balance. The statistical relationship between maps of vegetation cover and variables detailing surface properties acquired by satellite imaging was then analyzed.
The researchers also examined changes between different types of vegetation, including evergreen broadleaf forests, deciduous broadleaf forest, evergreen needle leaf forests, savannas, shrublands, grasslands, croplands, and wetlands. While deforestation results in overall higher levels of radiation leaving Earth’s surface, the balance between the shortwave light the sun emits and the longwave energy the reflects changes depending on forest type. From their observations, researchers concluded that removing tropical evergreen forest for agricultural expansion is the most responsible for an increase in surface temperature locally.
Altering the vegetation cover changes its surface properties drastically, affecting an increase in the level of heat dissipated by water evaporation and the levels of radiation reflected back into space. Overall, the researchers determined that land use change has made the planet warmer. Clearly, these forest ecosystems play an important role in combating the effects of air pollution, soil erosion, and overall climate change.
Gregory Duveiller, Josh Hooker, Alessandro Cescatti. The mark of vegetation change on Earth’s surface energy balance. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-017-02810-8