A carbon sink is described by Wikipedia as “a natural or artificial reservoir that accumulates and stores some carbon-containing chemical compound for an indefinite period.” Examples of natural carbon sinks include rain forests, oceans and soil. Rainforests have large role in Co2 levels.
Rainforests at a young age will remove CO2 from the atmosphere, however a full established rainforest is actually carbon neutral and simple can store CO2. This is still very important to the carbon cycle because CO2 can be stored in biomass in the rainforest instead of in the atmosphere causing global warming. According to EPA statistics forests accounted for about 10% of the United States CO2 sequestered. Due to the Kyoto protocol which allows trade of carbon emissions and using forestry as an offset, forestry has grown and the United States is planting more and more trees. With this being said 1 million trees can account for 0.9 tetra grams of carbon dioxide removal. The United States released approximately 5657 tetra grams of carbon dioxide in 2004. These facts lead us to the conclusion that the physical loss of forests has not contributed much to our current CO2 state. In all actuality the regrowth of forest removal is probably helping us more than if the forests were still there. With that being said I do realize that forest removal does cost some amount of carbon because of equipment used to remove forests and the small consumption of carbon that forests do have. I think the end conclusion is that you cannot contribute CO2 gains to forestry loss. Building new forests to help offset our present CO2 crisis is not a practical solution. According to benefit of trees in urban areas trees can store approximately 2.3 tons of carbon per acre per year and the average person consumes about that same amount. This means each person would need their own acre full of trees to offset their carbon footprint. That doesn’t include dropping our current state but only considering breaking even.
The ocean accounts for about ¼ of the earth’s CO2 natural sink, through the use of plankton and other biological processes. From Pre-Industrial to present day the oceans pH level has gone from 8.179 to 7.824. As the pH drops in the ocean multiple things happen. The first thing is that the animal life becomes less desirable and if it continues could cause massive issues for marine life. It also lowers the ability to capture CO2. Knowing that the ocean accounts for a very large amount of CO2 capture in the future we could see a even higher growth in CO2 if the pH continues to rise. With that being said the reduced the amount of CO2 that it takes in it is simply becoming saturated. That means that the CO2 crisis we are in now cannot be contributed to the oceans pH but rather the other way around. The good news is that studies are being done that use the ocean to reduce our current CO2 state. Adding Iron to the water stimulates growth of plankton. It has been found that each atom of iron added could contribute to removing 10 to 100 thousand atoms of carbon. Unfortunately the repercussions to marine life are unknown and at this point more research must be done before this can be done on a massive scale.
http://en.wikipedia.org/wiki/Ocean_acidification
Soil is the other big contributor to natural carbon sinks. CO2 is stored in soil through organic matter, roots and biomass. It has been shown most recently that farming and tilling of land is releasing oxygen and lowering the ability for the earth’s soil to capture CO2. Unfortunately not a lot of information on previous abilities of the soil to capture CO2 is available. However it can be predicted that if farmers used different tactics with their land soil could contribute to removing 10% of our projected CO2 use. From this I think it is safe to say that while soil could contribute to a solution it is not what put us in the CO2 crisis we are in.
This blog has reiterated that the current CO2 crisis causing global warming is not due to natural occurrences. It is even more unfortunate to know that earth’s natural resources will not contribute what we need to remove the CO2 we presently have.
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