Explainer: Forest carbon credits aim to offset pollution
WASHINGTON — For years, airlines have provided interested passengers with climate change one option: For an extra cost, remove carbon dioxide pollution from their portion of the flight, by paying to protect trees.
That’s the idea behind forest carbon credits. Trees absorb carbon from the atmosphere. Forest carbon credits are promises that companies, individuals and governments can buy to fight back emissions by paying to plant or protect trees. Here’s a look at this type of carbon credit.
What is forest carbon offset?
Imagine a forest that is in danger of being cut down for pasture or cropland. A broker arrives and promises to pay the forest owner — possibly the government — to prevent that from happening.
The land is officially designated as a carbon credit project. After that, the trees were not allowed to be cut down or destroyed by fire. The developer sells these promises and keeps some money. In the distance, a polluting company buys credits instead of reducing its own emissions by a certain amount.
Trees store carbon in their tissues, which means that the taller and healthier the tree, the more carbon it can store. Soil and vegetation also store carbon. When a tree is cut down, the carbon stored within it is usually released into the atmosphere. If the tree is sawn into large pieces of wood, some carbon is still stored.
How do they work?
a forest carbon offset, like any carbon offset, is equivalent to one ton of carbon dioxide being avoided, removed, or absorbed. A typical passenger car emits about 5 tons of carbon dioxide per year, according to the US I have to go to school every day.
Forest carbon offsets are a subset of ‘offset’ carbon billions of dollars market.
There are three main types of forest carbon offsetting: credits that sequester carbon by replanting trees, credits that protect trees from being cut down, and other credits that promise to improve forest management and increase carbon storage capacity.
How do trees sequester carbon?
Trees absorb carbon through their leaves, which makes them important for maintaining a livable climate. Through photosynthesis – the process inside plants that convert sunlight into chemical energy – they give off oxygen as a byproduct. Carbon is permanently stored in the fibers of the plant until it dies and decomposes.
Deforestation speeds up climate change in a number of ways: It stops plants’ photosynthesis, so trees can no longer absorb carbon. It is also often accompanied by combustion, which releases a lot of carbon dioxide.
What are some problems with forest offsets?
All types of carbon offsets face the same problem: Do they really work?
The forest carbon offset market has exploded over the past decade, with many policy makers see them as a way to combat climate change and even fund the transition to renewable energy. However, environmental groups, scientists and other experts argue that offset programs can cause to misunderstand.
“The problem here is that most voluntary carbon markets are self-regulating,” said Arnaud Brohe, chief executive officer of Agendi, a climate consulting firm and an expert on carbon markets.
Assessing the climate benefits of a credit is often difficult. For a forest carbon credit to be viable, it must do something for the environment that would otherwise not happen, an important concept known as ‘additionality’. Credits are only valid if those trees are in danger of being cut down. If trees are already protected, compensation is meaningless.
Another problem is leakage, which is when the protection of one forest leads to deforestation in another. There is also the problem of double counting sometimes, when the same credits are tallied in two different ledgers. For example, with limited regulation, credits granted to trees protected in a place may be charged by that country plus the country that purchased the credits or some other entity.
Experts say those selling forest carbon offsets often exaggerate the benefits to the environment.
“While projects may ultimately protect and preserve some land, the question is how much?” Danny Cullenward, a California-based energy economist and attorney who studies carbon emissions.