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Feb 18, 2009 05:20 PM | 7
The undisturbed tropical forests of Africa—like the rainforest in Congo—remove 1.2 billion metric tons of carbon dioxide from the atmosphere every year. For the last few decades, that rate of removal has increased by 0.6 metric tons per hectare per year—simply because the trees are getting bigger and bigger in size, according to an analysis published in Nature today.
That's good news for those who are looking for ways to sequester carbon, which many say is necessary to curb global warming. "We are receiving a free subsidy from nature," said study co-author Simon Lewis of the University of Leeds, in a statement. He and his co-authors measured the girths of tropical trees in Africa—and hence CO2 absorption.
All told, the world's tropical forests absorb some 4.8 billion metric tons, or 18 percent of manmade CO2 from fossil fuel burning and only a little less than the entire emissions of the U.S. In effect, tropical trees are getting bigger globally, perhaps because the CO2 is acting to promote growth as has been shown in other studies.
Based on current prices for metric tons of CO2, all that avoided greenhouse gas is worth some $18 billion, according to Lee White, chief climate change scientist of Gabon and a co-author on the research.
Some policymakers and scientists have argued that countries with tropical forests should be paid to preserve them. That could somehow translate into healthier economies in those countries, and jobs to replace those previously created by cutting timber or clearing forest.
Ultimately, however, the trees can't do that much more than they already are to save us. "Even if we preserve all remaining tropical forest," Lewis said, "these trees will not continue getting bigger indefinitely."
Credit: ©iStockphoto.com
Tags:
sequestration,
biodiversity,
climate change,
africa,
amazon,
old-growth forest,
rainforest,
nature,
global warming
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7 Comments
Add CommentSo, let me get this straight...trees are getting bigger and obviously thriving in a higher CO2 environment....Mother Nature is compensating for what may or not may be a natural increase in CO2 levels and this is still denigrated and downplayed by the AGW crowd.
Reply | Report Abuse | Link to thisI guess even Mother Nature falls short when it comes to the expectations of the faithful.
Just because part of the CO2 generated by us is being sequestered in the fast diminishing forests of Africa does little to stop rapid climate change. We do not look at evidence, we just talk based on unquestioning belief.
Reply | Report Abuse | Link to thisWe document 5 extinctions each of which almost destroyed all life on our little planet, we are charging headlong into the sixth. The rate of loss of species indicates we are in an extinction period. During the past 200 years the rate of loss of biodiversity has been catastrophic.
The only species increasing in numbers are Homo sapien and his/her favoured food and play species, plus species that gain from his/her destruction of their predatory species.
In the microbial world those that inhabit the world of the favoured species thrive, the rest have to find new hosts or go extinct. The HIV aids virus has made such a transition, it is non-pathogenic in its earlier host but will remain pathogenic till it and we evolve to live in harmony together. Other microbial species are trying to change hosts as their current host numbers decline. When a microbe changes hosts there is an adaptation period during which both species suffer trauma. Do you want to experience such trauma?
Keep biodiversity in place if you don't and control your your breeding rate. Give all life an opportunity to thrive. Extend your ideas of a multicultural world society to include all species.
Scientific earthling:
Reply | Report Abuse | Link to thisYou make the effortless connection between an increase in atmospheric CO2 and senseless debauchery of humankind. Huh?
Firstly, CO2 trails atmospheric temperature, not leads it, therefore it is impossible for CO2 to "drive" global temperature swings.
Secondly, Mann's Hockey stick is a laughingstick and utterly discredited. How can you even consider a model which cannot detect known historical events such as the Medeival Warm Period and the Little Ice Age?
Thirdly, 80% of all of the heat trapping effect of CO2 occurs within the first 20 ppm, after which the incremental effect of each CO2 molecule plummets. By the time we step out to 350 or 380 ppm, the effect due to CO2 is neglibible. Double CO2 to 700 ppm. It will make no difference, but as we see from the above article, the plants will love us.
Fourthly, The planet has been cooling for the last ten years, a fact that is utterly incompatible with all AGW computer models.
Now, if you want to talk about pollution (real pollution, not imaginary CO2 garbage), or about habitat destruction, or over population, I'm with you, But these are real issues; CO2 in the atmosphere is a fraud and a dangerous one at that, as it will drain valuable resources and manpower on the ultimate fairy chase, leaving nothing left for dealing with real issues.
Shoshin,
Reply | Report Abuse | Link to this..effortless connection.... debauchery of humankind - I don't know what you mean.
CO2: CO2 trails temperature? Give me a link. Build a greenhouse, add CO2 you will feel its effects. Moisture, CO2, Nitrous oxides, halogens all warming agents. Currently experiencing my hottest summer ever. Read the records of the hottest years, the majority are in the last ten years. Look at the hottest temperatures, the coldest temperatures and the temperature range. I am asking you to make an X bar R chart of temperatures. You will see whats happening.
Population: Less people more resources for all, less pollution, warming, cars, transport, land clearing. Resources for other species.
We are currently in a religious war of out populating the other religion. France faces the awful reality of becoming a majority Moslem nation in 20 years. The new majority will then change all the progressive laws that made it possible for them to become the majority.
Our population grows at the expense of almost every other species. A bio diverse planet survives and thrives, each species contributes and extracts from the biomass and the system is in balance. Eradicate all but a select few causes a mass extinction. In fact the sixth extinction is currently underway.
CO2 effects: Read this: The discovery of global warming http://www.aip.org/history/climate/simple.htm#L_0141
Last 10 years: Do the graph as requested remember it must be an X bar R graph. The range is important.
Resources: Yes I am with you on habitat, population, etc we disagree on CO2. Let me point out another resource we could disagree on MONEY. There are two types Fiat money, which is issued by countries and has value because we have faith in it, and debt. Banks issue debt against assets. Banks are the only institutions permitted to issue money. When you borrow money to buy a house, you provide you bank a valuation and you sign a note promising to pay the debt, with these 2 documents the bank creates the money on its computer. If you understand a bit of accounting it increases its assets by the value of the asset it receives title to and honours the cheque to pay the vendor.
For more about this: http://video.google.com/videoplay?docid=-9050474362583451279
Its no resource at all, its numbers on computers, an illusion.
Hmm
Reply | Report Abuse | Link to thisShoshin,
Reply | Report Abuse | Link to thisFrom your first post, it is evident you did not read and adequately comprehend the meaning of this paragraph:
"All told, the world's tropical forests absorb some 4.8 billion metric tons, or 18 percent of manmade CO2 from fossil fuel burning and only a little less than the entire emissions of the U.S. In effect, tropical trees are getting bigger globally, perhaps because the CO2 is acting to promote growth as has been shown in other studies."
The debate is over (among non-politicized parties), the >increased< sequestering of CO2 still only absorbs 18% of global output. Explicitly, the article states that this sequestering cannot do much more. It is not likely that the total area of tropical forest will "grow" but is shrinking.
Mother Nature is NOT compensating for the human-contributed CO2 output. That you would conclude this: shows that you've adopted the disproved and untenable pseudo-facts and pseudo-reasoning of profit-motivated corporate political operatives. It's the oldest scam in movement building: tell people what they want and expect to hear and you will gain followers.
If the forests absorbed all the excess atmospheric CO2 they would have to grow five times as big...
Reply | Report Abuse | Link to thisOther studies show that 'CO2 - enhanced' growth is limited, as the trees also need extra (bacterially-fixed) nitrogen, potassium and phosphorous to grow bigger. There's no such thing as a free lunch!