2011 International Year of Forests: forests and climate

This post is also available in: Dutch.

Forest in the Ardennes (Belgium)

The lungs of the earth

Forests worldwide do more than just provide a habitat (a place to live) for plants and animals. The large numbers of trees and other plants in forests supply the oxygen that humans and other animals so desperately need to survive. The name “lungs of the earth” is often used. During this process of oxygen production the tree will take up large amounts of CO2 (carbon dioxide) in its leaves, which through a chemical process, called photosynthesis, is converted into carbohydrates (starches) that the tree uses for growth. In this process oxygen is released, basically waste. But ‘waste’ that forms the basis for animal life. A significant amount of the absorbed CO2 is stored in the leaves, roots and branches of trees.

Influencing global climate

However, forests have more impact on the earth than we initially suspected. Forests also affect the global climate, and are therefore “players” in the battle against global warming.

The capture and storage of CO2 in the tree is the punch line. The burning of fossil fuels (like oil and coal) caused an explosive increase of, among others, CO2 levels in the atmosphere. This gas ensures that the heat of the sun entering our atmosphere, which normally should be reflected back into space for the most part, will remain in the atmosphere. This so-called greenhouse effect results into warming of the atmosphere, and is directly responsible for melting of the polar ice caps and glaciers.
Forests can counter the greenhouse effect, because of the capacity to remove CO2 from the air and store it in other chemical compounds. Forest can balance the CO2 levels in the atmosphere, but only if enough forest area is kept in a healthy state, logically. A welcome relief to the climate related doomsday scenarios, though.

Air conditioners of the Earth

Forests are influencing global climate on more levels, however. Greenpeace calls rain forests the air conditioners of the earth. Because rain forests are always hot and humid a lot of the fallen rain will evaporate continuously. The water vapor cools the air above the forest and this process directly influences the climate in a good way.
Main conclusion: forests are indispensable in the fight against climate change!

Forest with waterfall on the island of Dominica, even in these relatively small rain forests significant amounts of CO2 are stored in the branches, leaves and roots of trees and plants, but also in the soil.

Destruction

This conclusion is unfortunately not mainstream, proven by the fact that primary forests are disappearing at an alarming rate. Every minute an area of Amazon forest the size of six football fields is cut down. The rate of disappearance elsewhere in the world, including in Indonesia and Congo, is not much less. Most of the captured CO2 in each section of forest that is cut down will be released back into the atmosphere (through burning of the trees), and the capacity for future storage is reduced.

The protection of forests seems to be an easy task. Just leave the forest alone, is what many people think. The big problem is that most tropical forests are located in relatively poor countries. Those countries have little budget for basic infrastructure, let alone conservation measures. Large multinational logging companies specifically target these countries because there are little or no regulations, wages are low, and therefore wood can be produced at low cost but with maximum profits.
Often large areas of forest will be burned down for agricultural and livestock raising purposes, mostly illegal practices which are fed by the expanding population and exponential demand for food for both humans and animals. The ‘big picture of global climate change’ obviously plays no role in the daily struggle for survival of the farmers concerned.

Reforestation: the solution?

Reforestation is often presented as a simple solution to global warming. If only we could plant enough trees global warming will be solved automatically. Many of us gladly participate in such schemes mainly to feel less guilty about the greenhouse gases emitted by another overseas vacation trip. Reforestation is okay, but will certainly not be the solution to the problem. The world is demanding more and more food and ever more energy. The increasing world population requires more food, and so more forests need to be turned into agricultural land. We all want our own car, to go on vacation in foreign paradises, and eat shrimps from the Philippines. All fossil energy-guzzling wishes. Poor countries would like to develop to the level of wealth of the rich countries, and thus to the energy behavior of these ‘slurpers’. It seems to be a vicious circle of which it is doubtful that the world can escape from.

About Michelle da Costa Gomez