World's vegetation is cleaning more carbon from skies

The Christian Science Monitor ^ | June 06, 2003 | Peter N. Spotts

[presidio9]

If your dogwoods and peony patches are looking a bit more robust than they did 20 years ago, you may have climate change to thank for much of their growth. Using two decades' worth of data on climate and vegetation, a team of scientists has taken what may be the first planet-wide look at plant activity during a time when Earth's environment underwent significant change.

The researchers found that globally, shifts in rainfall patterns, cloud cover, and warming temperatures triggered a 6 percent increase in the amount of carbon stored in trees, grass, shrubs, and flowers.

Many scientists hold that the growth in atmospheric concentrations of heat-trapping carbon-dioxide - from nearly two centuries of rapidly growing populations that burned increasing amounts of fossil fuels - is largely responsible for the earth's warming climate.

The new research adds to the body of evidence that plants can store increasing amounts of carbon from the atmosphere, but it remains unclear how long this trend will continue or whether it will significantly affect atmospheric CO2 levels.

Kyoto provisions

The 1997 Kyoto Protocols - a first step at trying to reduce emissions and so moderate the change - permits countries to use the carbon-absorbing capacity of their forests and farmlands as credits against their emissions targets. In addition, projects that increase vegetation also are seen as ways to reach national CO2 emissions targets. Thus, understanding the flow of carbon from the atmosphere to plants and back is vital to projecting future trends in atmospheric CO2 levels.

For 50 years, scientists have been measuring the growth of CO2 in the atmosphere, according to Ramakrishna Nemani, a professor in the forestry school at the University of Montana in Missoula, who led the research team. "But if you look at the record of the past two decades, the annual growth rate hasn't been going up like it had before," he says.

Other groups had forecast an increase in plant growth for a time with climate change, although rates would vary depending on region. And some smaller-scale studies had indicated that the earth was greening.

Dr. Nemani's team was interested in seeing how plant activity had changed - and where - worldwide during a 20-year period that saw two of the warmest decades ever recorded, several intense El Nino episodes, one major volcanic eruption, a 9 percent increase in atmospheric CO2 concentrations, and a 37 percent growth in human population.

The team measured how much carbon plants store after absorbing carbon dioxide through photosynthesis and returning some of it through respiration.

First, the team built maps reflecting changes in temperature, cloud cover (which affects the amount of sunlight reaching plants), and available water. Then they overlaid satellite data on net primary productivity on land and looked for relationships among these components.

Big change in the Amazon

They were stunned at the growth rates in South America's Amazon region.

"That was a big surprise," says Ranga Myneni, a botanist at Boston University and a member of the research team. Amazon rain forests accounted for nearly half the increase seen globally over the 20-year period.

The surprise was twofold. The growth rate far exceeded what most scientists expected. Many models indicated that additional growth in the tropics would be minimal, given the fairly constant temperatures from one season to the next. In addition, many researchers had held that any increased productivity in the tropics would largely be driven by a rise in atmospheric CO2 rather than changes in climate itself.

Yet the drop in tropical cloud cover during the period allowed more sunlight into places like Amazonia, Dr. Myneni says, far outpacing CO2 as a prod to growth. Likewise in other climate regions, changing Climate conditions appeared to be the dominant factor driving plant growth.

The other half of the equation

The good news for plants, which appears in Friday's edition of the journal Science, comes with caveats, Myneni cautions. Since humans collectively use about half of plants' net primary production, he says, the team's estimate of 6 percent growth over 20 years translates into a trivial 3 percent growth in material available to a growing human population.

Moreover, the 20-year period the team studied could be unusual, and hence not representative of long-term prospects for vegetation growth. And if the climate continues to warm, as many expect, plants will bump up against limits to their ability to make use of the additional water, warmth, and sunlight, just as they bump into limits on the amount of CO2 they can use. The study also doesn't answer questions about how changing climate conditions in these areas are affecting the amount of CO2 given off from plant decomposition and soil - amounts that can offset the CO2 that plants imprison in their roots, stems, and leaves.

"That's the other half of the equation" the study doesn't address, he cautions.

[skeeter]

I only enter the fray briefly for the conservative cause, so that in the annals of global warming history, they can't paint us all as idiots.

Then educate us 'idiots'.

You claim 'global warming from manmade causes' is a widely established fact.

It shouldn't be too difficult for an expert such as yourself to name the scholarly sources establishing this fact?

[Carry_Okie]

I have read elsewhere that anthropomorphic causes for increased carbon emissions comprises about 3% of the entire amount of the total increase that "causes" global warming.

That would be "anthropogenic."

[brewcrew]

I only enter the fray briefly for the conservative cause, so that in the annals of global warming history, they can't paint us all as idiots.

You are buying more than you're selling, sir or madam. And when you buy more than you sell, you lose.

It is, indeed, scientifically provable that the mean temperature of the earth has risen slightly over the last century. To claim absolute knowledge of the cause of this phenomenon is arrogant and self-centered. 100 years in geologic time is less than the blink of an eye.

[sauropod]

Anthromorphic. The CO2 cloud took on the shape of Kofi Annan ;-).

[Orbiting_Rosie's_Head]

Um, hello. The entire scientific community has reached consensus on this point. I don't think I'd even bother debating with a patzer that doesn't get that point.

Whoop! Whoop! Whoop! Warning! Disruptor alert...Here's how your "consensus" is manufactured. BTW I generally discount anyone who starts a sentence with "I don't even bother to debate........" as someone who is in possession of no facts.

[Orbiting_Rosie's_Head]

should have included the following link in my last post:

Rand Institute Exposes Global Warming Fraud

[js1138]

All I know is I have to mow more often.

[FreeTheHostages]

Nonsense, my whole point is that the facts don't support the position of the poster. And that the question of whether there's significant manmade contribution to global warming is a scientific, not a political, question. The whole reason it's not worth feeding the trolls and getting in a debate here is because we don't have consensus on even that yet here at FR! So why bother with facts since people scream politics back?

I'm very upfront about registering that point of view but *not* getting in debate about it. Declare whatever adverse presumption you care to. Fact is, I refuse to engage in a battle of wits with unarmed people.

[FreeTheHostages]

lol

now you're scaring me, 'Pod

[Iconoclast2]

Science is not a consensus process. People who accept global warming because of a claimed "consensus" are just ignorant, and have a mindset more akin to liberals. When global government comes, and freedom dies, it will happen by "consensus".

[FreeTheHostages]

It is, indeed, scientifically provable that the mean temperature of the earth has risen slightly over the last century. To claim absolute knowledge of the cause of this phenomenon is arrogant and self-centered. 100 years in geologic time is less than the blink of an eye.

I stand on 450,000 on Vostok -- and probably back 1.5 million based on post-Vostok ice cores.

This is a scientific question, not a political one.

There should be more threads about conservative solutions to global warming -- or honest scientific debate about the extent to which vibrant sinks can continue to absorb the CO2 or other changes (increased vegegation, e.g.) can give us a relative steady state. But to just sit here and say it's not the case -- that seems rather wrong. Generally, I like to think that conservatives stick closer to the truth. So I call y'all on departing on it. It's a mistake and you risk making us all look silly if you buy some BS on a website saying there's no manmade global warming. C'mon, good people, we're supposed to be the educated ones.

[FreeTheHostages]

Ah, fascinating. Scientific consensus is just that. And saying science is not a consensus process -- well, I suppose one can quote iconoclastic sources that depart from mainstream science. But to say there's not a stream, and a mainstream -- well, that would be wrong too.

[presidio9]

Nonsense, my whole point is that the facts don't support the position of the poster. And that the question of whether there's significant manmade contribution to global warming is a scientific, not a political, question.

See that's where you are wrong. There is no scientific basis to the global warming theory. Liberals have filled your head so full of mush that you think there is. But until we are give even the slightest bit of concrete evidence of Global Warming, it would be a serious mistake to ally ourselves with Al Gore and his storytellers.

[Coleus]

bttt

[FreeTheHostages]

a scientific, not a political issue: Is there a significant manmade contribution to global warming?

a political, not a scientific issue: Whether there will come a time when "global government comes, and freedom dies."

You say that the latter will come, if it does, on "consensus." Hmm, I think the latter will come, if it does, because people twist the truth and the facts to their own political ends. If there's one think the Gulag Archipelogo taught me long ago, in 8th grade, it was the importance to Stalin -- and to all totalitarian regimes by extension -- to twist facts and kill the truth and history for political expediency.

I'm a conservative because, frankly, most of the time conservatives are right. And as a general rule, they're much less likely to twist the truth. But it's the truth that will set you free, and if you ever depart from the facts, in my opinion that's the beginning of going in the wrong direction politically.

Saying something doesn't make it so. It's not that I like the greenies any more than you guys do. I eat lots of meat. But it's time to start talking about what the conservative position *on* global warming is, not *whether* there's global warming.

It's fascinating, for as often as I've said it, that so few will reach consensus here in this thread on at least this fact: that the question of whether there is or isn't significant global warming caused by human industry is a scientific, not a political, question.

Let me really annoy you all and say this: I really really hope solar or something becomes financially viable some day. And gets us out of the dependence on Arab oil. And somehow -- in some sci fi future -- is manufactured and consumed in a way that doesn't create even more CO2 and methane. That's not today. But if that day comes, it will come as a result of people who followed *facts* and were *scientists,* God Bless 'em all, and these scientists could well be the free market solution to a real problem.

I'm not for Gore's treaty -- I'm not for China and India continuing their emissions while we just stop industrializing here in the West. I'm not for any of the liberal solutions to the problem. So this "you're just a disruptor" stuff, along with all the other name calling -- it's all just highly, well, counterfactuals.

It's the truth that will keep us free. Always be on the right side of reality, y'know?

[gatex]

"...And that the question of whether there's significant manmade contribution to global warming is a scientific, not a political, question...."[bold added]

Define significant ---what percent ?

[Hanging Chad]

"...global warming from manmade causes is a *fact* -- a matter of general scientific agreement -- and we shouldn't be debating whether it exists ..."
- - -
I am a member of the "scientific community" and I do not buy-in to this theory.

The actual "facts" as you call them are few and far between. Is there any warming? How much? Based on what "norm"? Over what period of time? And then once such that 'fact' is established lets make a causal link to some 'human activity'. Which activity in particular? and over what time period?

Hey Chicken Little !
THE SKY IS NOT FALLING !

[Carry_Okie]

C'mon, good people, we're supposed to be the educated ones.

So why not try getting educated? There's no argument contrary to the claim that the atmospheric concentration of CO₂ has increased; there is however, no proof, or even strong indication that the anthropogenic contribution to that change has even a marginal effect on global tropospheric temperatures. Worse, there is every indication that any Kyoto-style effort to reverse that change will have NO MEASURABLE EFFECT on global temperatures 100 years from now. Even the IPCC's bogus models indicate that, particularly when the published error factors in the models are taken into account.

[gatex]

What can you tell us about (1) limestome deposits and (2) the equilibrium CO2 content in sea water ?

[balrog666]

global warming from manmade causes is a *fact* -- a matter of general scientific agreement

BWAAAAAAAAAAAAAHAHAHAHAHA! Are you just a random troll or a deluded greenie?

If you're referring to the IPCC reports, the scientists who compliled the data refused to sign on to the political conclusions that were tacked on in the executive summary.

If not, what kind of drugs are you on?