We put a lot of carbon into the atmosphere, 43 billion tons in 2019 alone. Atmospheric carbon levels are the same as they were 3million years ago. Back then the Earth was 2-3 degrees centigrade warmer and sea levels were 15-20 meters higher. Eek.
Clearly, something has to be done if we want our children and future generations to enjoy the same standards of living as we do. Scientists believe ‘safe’ levels of carbon is 350 parts per million. Currently, we’re at 409.8 parts per million. This means we’re going to have to become ‘carbon negative’, meaning that we have to remove more carbon from the atmosphere than we emit.
Here are the ways that carbon gets absorbed, or sequestered to use the posh term, from the atmosphere.
Our oceans do a lot for us. They’re vast systems that influence the climate, weather, ecosystems, and human livelihoods. There’s still a lot we don’t know about them, but what we do know is that they absorb large volumes of CO2 from the atmosphere. In fact, it's estimated that the oceans absorb 31% of global emissions.
However, this isn’t good as it’s resulted in increased ocean acidification and rising surface temperatures, threatening vital marine ecosystems such as coral reefs. We also can’t rely on the oceans to keep absorbing CO2 at current levels.
Large amounts of carbon are absorbed by natural ecosystems we need to protect
Trees absorb large amounts of carbon over their lifetimes. They also provide a nice place for animals to hang out, for us to sit under in the summer, and help with water purification and land regeneration. Many carbon offset programmes use tree planting to remove carbon emissions (ours is the Zambia Tree Project). Planting an area of trees the size of the US has the potential to erase 100 years of carbon emissions. Of course, it’s vital we protect existing forests and ecosystems too.
The Zambia tree planting project
Beyond trees, other plants such as bamboo are also extremely effective at absorbing carbon and can be sustainably harvested. Soils come into play by absorbing the carbon from dead plants and animals. It’s thought that the Earth’s soils actually contain 3 times more carbon than is in the atmosphere, so protecting and replenishing soils is vitally important also.
As well as natural solutions, there are a few artificial carbon capture solutions being developed. Direct air capture is such a technology. Essentially, air is blown over substances that bind to the carbon specifically. This technology is still young, and expensive, especially when compared to planting trees, however some benefits are that it can be set up almost anywhere and the captured carbon can be useful for other things, like fizzy drinks.
The overwhelming scientific consensus is that we need to first reduce our greenhouse gas emissions to zero to alleviate the need for carbon removal as much as possible, because once the carbon has been emitted it takes time and additional energy to remove it. We need to decarbonise our whole economy. Here are the most effective ways that we as individuals can do out bit.