The Impact of Deforestation on Climate Change
Large swaths of the world’s forests are cleared every year to make way for commodity crops like beef and palm oil. This deforestation releases massive amounts of GHGs and also alters local and global precipitation patterns, making it a major contributor to climate change.
The modeled temperature response to deforestation in high, mid and low latitudes is consistent with previous studies. However, the simulated drying of land is less pronounced.
Across the globe, the majority of deforestation is caused by people clearing land for farming or to make space for housing. Most of this is a result of the growing population and increasing demand for food.
Subsistence farmers often use slash-and-burn techniques to clear forests and grasslands for planting and feeding their families. Using these small scale methods means that the forest can often recover from the initial loss.
However, when more than 25% of a forest is cleared it can have a significant impact on the local climate. This is because the bare ground will reflect more sunlight back into the atmosphere. This has a net warming effect in the short term. It also affects the carbon cycle, storing more carbon in the air over time.
Deforestation contributes to climate change in several ways. Firstly, the carbon released when forests are cut down enters the atmosphere and enhances the greenhouse effect. This is because carbon dioxide absorbs solar thermal energy and increases Earth’s temperature.
Additionally, the loss of trees decreases soil moisture, which can lead to drought. Dryer areas will heat up more rapidly, leading to a vicious cycle that can be very hard to break.
Another way that deforestation impacts climate is by altering land albedo. When trees are removed, the bare ground becomes much more reflective, meaning that sunlight is absorbed by the surface and doesn’t radiate back into space. This is one reason why tropical regions often experience droughts after deforestation. It can take decades for land ecosystems to recover from drought.
Many people think of environmental concerns as very modern issues, the result of population growth and increasing consumption. But the destruction of natural habitats is a problem that goes back millennia.
Deforestation is one of the primary causes of greenhouse gas emissions, releasing carbon dioxide into the atmosphere. It also contributes to climate change by reducing the albedo of the land, meaning that more sunlight is reflected away from Earth instead of absorbed, leading to an even warmer planet.
Forests are also home to a wide range of species that provide vital food and other resources for people around the globe. Unfortunately, these trees are often cleared to make way for farming. This is especially the case in tropical countries where people want to grow crops like soy, palm oil and beef to sell to their global neighbors.
Deforestation has long been linked to carbon dioxide emissions and global climate change, but researchers are now recognizing the non-carbon impacts as well. Clearing forests can dramatically affect local climate, including changes to rainfall and water supply.
Forests act as a natural filter for incoming water and reduce flooding risks. When they are removed, rivers and lakes have difficulty absorbing precipitation and droughts may happen more often.
In addition, trees influence how much sunlight reaches the ground by changing land albedo, or how much of it is reflected back into space. When they are cleared, bare surfaces absorb more sunlight and temperatures can rise. This is one of the reasons that regions which experienced significant deforestation in the 1980s have seen a faster increase in hottest day temperatures than others.
As forests are cleared they release stored carbon and also block weather patterns, leading to droughts and flooding. As a result, cutting emissions from fossil fuels is the most urgent task to avoid more global heating.
Clearing forests to make room for agriculture is a major cause of deforestation. In tropical areas, farmers use slash-and-burn agriculture to clear land for logging, cattle ranching and oil palm and rubber plantations.
In addition to releasing greenhouse gases, clearing forests leads to an increase in infectious diseases. A study of the occurrence of malaria in Borneo found that the warm, open spaces that occur after forest clearance provide better habitats for mosquitoes that transmit the disease. Additionally, the lands become fertile breeding grounds for snails that carry the parasite schistosomiasis that damages human organs.