Smoking industrial chimneys, exhaust fumes, fires in the Amazon — yearly carbon emissions recently swelled to 12,000,000,000 tons (12 gigatons).And as carbon increases, so do temperatures.
Around half of emissions released remain in the atmosphere. Nature The rest is absorbedHolding it in carbon sinks like soil, oceans, or vegetation. These natural storage solutions slow climate change far more effectively than any human technology — carbon storage factories store just 40 megatonsannual CO2 emissions or 0.003% of all anthropogenic emissions.
Natural carbon sinks could perform even better with a little tweaking and for a comparatively small price tag. But humans are destroying more and more natural CO2 sinks, damaging our most successful tool to halt a climate catastrophe.
Nature struggles to keep up
Humans have increased their carbon emissions rapidly by burning fossil fuels. This has led to an increase in the amount of CO2 that is absorbed by plants and soils. A high level of CO2 means that plants need to open their pores for the gas to be absorbed. This allows them to lose less water, and is more able to survive droughts.
The amount of greenhouse gases in the atmosphere is increasing rapidly because humans are now producing more carbon that nature can process.
Vegetation sinks – Trees for the Climate
The total amount of CO2 absorbed by the world’s forests each year is 15.6 gigatons. This is three times more than the amount that’s absorbed by forests around the world. Annual CO2 emissionsUnited States. Forest fires and deforestation account for around half of the greenhouse gases that leak back into our atmosphere. Deforestation is responsible for around a fifth all greenhouse gases produced by humans worldwide.
For example, the Amazon rainforest is one of the most important carbon sinks in the world. But since Jair Bolsonaro became Brazilian president in 2019, more and more of this vital ecosystem is being lost.
Conversion of forest to agricultural land means the Amazon basin now emits as much carbon as the remaining forest can sequester. It could soon be like the tropical forests in Southeast Asia that emit more CO2 than they absorb.
The establishment of additional forests can help increase the carbon sink for vegetation. The new woodland absorbs the carbon dioxide. More carbon than the old stockIt produces lots of new biomass. However, planting new trees is not the best choice, according to Jared Messinger, manager, Global Restoration Initiative, at the environmental research organisation, the World Resources Institute.
“You know, continuing stewardship and longevity of the program with tree planting — and [the involved] mortality rate — is very costly,” said Messinger, adding it would be cheaper to let forests grow naturally in open areas.
Young trees could reduce atmospheric CO2 by up to 23% by growing on land that has been cleared. According to the WRI. Particularly effective in humid, warm areas of West Africa and Central Africa would saplings be.
Forests require considerable land, however, to be effective carbon sinks — and with a growing demand for food, they will have to compete with agriculture for that land. Any stored CO2 that is not used would be released into the atmosphere, negating its positive effects.
Soil sinks: The secret climate heroes of the Peatlands
While soil absorbs CO2 slower than vegetation, it has a higher level of carbon storage. Carbon makes up about half the soil in Central Europe.
The soil is a major source of nutrients worldwide Nearly twice as much CO2as both living flora, and the atmosphere. However, soil type, vegetation, and climate all affect how it stores carbon. The better the soil is, the more it is wetter, and the colder. Particularly large quantities are found in soils under northern boreal forests or temperate grasslands.
Photosynthesis is when plants store carbon as sugar. This carbon often remains in the soil even after the plant dies.
The carbon sink champions are peatlands and marshes. Although they account for around a third the CO2 absorbed from soil worldwide, they are only 3% of the global land area.
Plant debris is able to sink into these wetlands and it becomes slightly acidic. The debris doesn’t decompose in this oxygen-poor environment and instead turns into carbon-storing peat.
The layers beneath the peatlands are exposed to oxygen by draining them. This triggers a process of decomposition that releases CO2. Oxidation Also, nitrous oxide is producedThe greenhouse gas ozone is approximately 300 times more dangerous than carbon.
Peatlands and wetlands around the globe are under threat despite their incredible abilities. Peat forests in Indonesia are being replaced by palm oil plantations. They also are being destroyed through forest fires that generate huge amounts of emissions. Germany has now drained nearly all of its peatlands. Only 0.2% of the original area of 5% remains.
How can dust be used to fight climate change?
Dust, or basalt dust, may improve soil’s ability to store carbon. According to research published in peer-reviewed journals, dust reacts with soil water and CO2 when it is scattered on the fields. Nature Geoscience. These particles then get washed into the oceans and lakes, before being deposited as soil.
It can also happen naturally. It happens more quickly in finely ground basalt due to its larger surface area. Basalt also produces minerals that increase plant growth in nutrient-poor areas, which would allow it to store more CO2.
Spreading basalt dust on arable land could increase soil’s carbon storage
If basalt were spread once on an area of arable land, it would be enough to store 2.5 gigatons per year. This is equivalent to India’s annual emission. Others estimate that the climate benefit could be twice as high. Basalt can be obtained easily even without the need for new mines. It is a byproduct of steel and cement production.
The productive seas sink to the ocean
Still, vegetation and soils cannot match the enormous potential of the oceans. The oceans can store as much as 80% of the carbon in the world. They could absorb, theoretically. 95% of greenhouse gases that are human-madeBut this would be too slow.
The annual carbon cycle of trees stores carbon. It takes decades for CO2 particles to sink to the surface and be stored in deep sea. At the same time, carbon concentration at the surface lowers absorption of new emissions.
Cold water absorbs more CO2 then warm water, and oceans’ capacity to absorb carbon dioxide is decreasing as a result.
Are algae farms natural CO2 sinks
However, it is not only the water that can store carbon dioxide: Algae and seagrass also have the ability to do so. Seaweed alone can eliminate CO2 0.173 gigatonsResearchers estimated that there are approximately 1.2 billion tons of carbon in the atmosphere every year, before it sinks to the sea floor. Nature Geoscience.
Companies like Pull to RefreshThey are testing giant kelp farms out at sea to sequester CO2.
How about the price tag?
Nature is helping us to reduce climate change, whether it’s through trees, moors, or oceans. Basalt fertilizer, new forests on land or seaweed could boost the carbon-sucking potential of natural sinks.
However, this comes with a cost. Forests, for example remove carbon from the atmosphere, but at a price of $7.50 to $27 (€6.60 to €23.60) per ton of CO2. Basalt fertilization costs between $80 to $180.
It’s It is cheaper to not burn carbonInsulation, green energy and conservation are the best ways to reduce carbon emissions.
“Cutting emissions are the most important thing we could do. Jared Messinger, World Resources Institute, stated that cutting emissions is the most important thing we can do.
Translated from German by Elliot Douglas