During the Middle Ages, the Catholic Church offered grants, allowing people to exchange donations for papers that promised reduced laundry time after their deaths. Less controversially, today someone who delivers too much tea supply to the office may feel compelled to pay for a replacement box. Do carbon offsets look more like the first or the second?
There are many reasons why you might want to compensate for some of the carbon footprint, whether it is to provide a general sense of guilt for your lifestyle, to accurately cover the estimated emissions of a flight, or simply to do something beneficial for the environment. Regardless of the motivation, all these efforts are based on the belief that the money you actually paid will lead to the abolition of the promised amount of CO2 from the atmosphere. Otherwise, you pay for a lie – or at least get a smaller tea box than the one you ordered.
Finding out if you are lying is really difficult. Here you need to know.
Reduction of the carbon cycle
Carbon dioxide in the atmosphere is part of a bio-geochemical dance called the carbon cycle. Coal regularly changes the shape and code of the area, cycling between the atmosphere, oceans, ecosystems, and even the foundation. Plants receive carbon atoms from CO2 in the air to grow. Vegetarians consume plants and exhale carbon as CO2 again. Weather rocks pull CO2 out of the air. Volcanoes release it into the atmosphere. These are just some of the goal setting shareware that you can use.
Before the Industrial Revolution, these flows were balanced, maintaining a constant concentration of CO2 in the atmosphere. But then we discovered fossil fuels and their ways of lighting for fun and profit. This took more and more carbon that had spent many millions of years locked deep underground and released it into the atmosphere. Part of this carbon (just over half, in fact) was absorbed by the oceans and terrestrial ecosystems. But the rest accumulated in the atmosphere, pushing the concentrations of greenhouse gases higher and higher.
To stop the growth of this greenhouse gas, the net total CO emissions2 must reach zero. It is so simple. We can achieve this in part by eliminating emissions caused by some of our activities. But we will probably also have to compensate for the continuing emissions to reach zero.
Some carbon offset projects help with this by preventing emissions that would otherwise have occurred. Others promise to keep what is known as a “sink” in terms of carbon cycle – a durable form of carbon like forests or even carbonate in the soil. These compensations are not always identical to the prevented emissions, as they can have carbon-specific climate effects. Forests, for example, may be darker than their surroundings, so their expansion leads to local warming as more sunlight is absorbed. However, reforestation is also accompanied by the possibility of providing other ecosystem services, such as animal habitats. So there are many factors besides carbon that you need to consider.
Do like a tree and a leaf
Planting trees is an incredibly simple answer to climate change. (For evidence, see: comments on the Internet.) But our ability to store carbon in this way is finite. We could undo the deforestation emissions in the past, but we can never install enough to cover the rampant use of fossil fuels. But even if you accept this restriction, a lot can go wrong once your plants get into the soil.
Assuming you find a program you can trust to actually plant the promised trees, many things will affect the effect of the carbon cycle over time. The first is the way the tree species grows. Some are growing rapidly, accumulating a lot of carbon per acre over the last decade or so, which provides immediate help to the carbon balance sheet. But fast-growing trees are usually less dense than slow-growing species, so the final amount of carbon stored per acre is lower.
Faster growing species also tend to have a shorter lifespan. If the trees in this plantation are managed for harvest, the end of life will happen sooner. Then where does the coal go? Some, could be converted into wood, at which point its value as a carbon sink depends on how long things built with this wood last, the remaining plant material decomposes or burns, releasing carbon back into the atmosphere, which ends the her time as a sink,
Even if planted trees are never harvested, their carbon could be released in other ways. Old trees die and rot, of course. Bug infestations can penetrate forests, killing trees en masse. Fires can do the same. Some risks like these are increasing due to climate change, which means that coal storage in forests is becoming less and less secure over time in many areas.