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A Hidden Loop In the Carbon Cycle Discovered
Posted by
samzenpus
on Wed Aug 06, 2008 08:11 PM
from the hot-and-heavy dept.
from the hot-and-heavy dept.
Googlesaysmysiteisdangerousanditisn't! writes "A recent article in Science says that researchers in China and the US have found massive carbon uptake in the world's deserts. The effects of this are huge. 35% of the Earth's land surface is desert, and the uptake equates to 5.2 billion tons of carbon sequestered each year. This is more than half of the carbon released by humans. In these 'dry oceans,' the grains of sand allow the carbon dioxide to enter and react with alkaline soil to become carbonates. Another scientist suspects that biotic desert crusts, alkaline soils, and increased precipitation may be driving the uptake."
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Obviously (Score:5, Funny)
Not just a joke (Score:5, Interesting)
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South Park Did It (Score:5, Funny)
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Not the whole story (Score:3, Insightful)
Methane doesn't stay in the atmosphere as long as CO2.
Re: (Score:3, Informative)
Re:Not the whole story (Score:4, Interesting)
Just a thought but perhaps this new discovery is connected to the "missing methane"?
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Re:Not the whole story (Score:4, Interesting)
The most pessimistic estimates of the (winter) 2007 IPCC report had the summer Artic being "ice free" by around 2050, GHG "alarmists" at the same time were saying ~2030, now 2015 is looking not unreasonable. Last years melt was so dramatic that large shipping companies have been seriously contemplating the feasiblity of opening new shipping routes across the pole. Meanwhile a considerable number of scientists are still looking behind the couch for the missing methane.
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Re:Not the whole story (Score:4, Interesting)
Well yes, it's the middle of winter down here.
Aside from that the Antartic is pretty much behaving as expected ( more snow up high, more melt around the edges ). The one place that is changing rapidly is the Antartic pennisula where temp rises have been three times the global average because of a phenomena known as polar amplification. Polar amplification has been forecast by the models since the 90's.
Even if you think we are not facing serious changes to our climate that could descimate global food production, surely a drastic reduction in the use of fossil fuels would go a long way to solving some of the other problems you mention. Personally I would like to see all pollution cleaned up but that's not going to happen in my lifetime.
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Re:Not just a joke (Score:5, Insightful)
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Re:Not just a joke (Score:4, Funny)
That really depends on what the homeowner does with the grass after it is cut. If it goes in a land fill most of the carbon probably stays underground. If if goes into a compost heap then more of the carbon goes back into the atmosphere.
Although I personally think laws waste a lot of resources (especially in LA where I live).
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Re:Not just a joke (Score:4, Funny)
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Re:Not just a joke (Score:4, Informative)
http://www.abc.net.au/science/articles/2008/08/05/2324476.htm [abc.net.au]
Wild untouched forests store three times more carbon dioxide than previously estimated and 60% more than plantation forests, a world-first study of "green carbon" and its role in climate change shows.
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Re:Not just a joke (Score:5, Insightful)
True, but CH4 + 3O2 -> CO2 + 2H2O, which won't take long in an oxygen-rich atmosphere, and just gives us carbon dioxide back; the same carbon dioxide that was absorbed when the leaves grew in the springtime. Meanwhile the tree on the ground has grown over the course of the year, and locked up a bit more carbon in the form of wood.
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Re:Not just a joke (Score:4, Interesting)
In other words, pump as much steam as you like into the atmosphere and all it will do is fall out as rain/dew somewhere else.
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Re:Obviously (Score:4, Informative)
Sure, as long as you don't skimp on the sandworms.
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So, deserts are good? (Score:4, Interesting)
Does this mean that scientists now think that we don't have enough deserts?
I'm all for global warming (it is cold up here in canada), but I'm pretty sure we've got enough desolate landspace...
Re:So, deserts are good? (Score:5, Funny)
If it gets too hot in the USA, guess where we're going to move to. That's right, and we're bringing our army too. Don't be wishing for global warming until you've thought the whole thing through.
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Re: (Score:3, Funny)
Usually this would be where someone makes a sarcastic comment about you liberating the polar bears...but if you could just kill Celine first then I swear we really would welcome you as liberators.
Re: (Score:3, Funny)
...because we've already taken her off your hands and stuffed her into one of our desert hell-holes.
Holy shit. Deserts sequester Carbon and awful musicians?! Excuse me, the local bands in my city suck. I'm off to chop down a few trees...
At what point does ythis break down? (Score:5, Insightful)
Ok. So they've found a massive carbon sink that was unaccounted for. Great!
They also say that due to changing conditions, including increased precipitation, there is more uptake occurring.
Does this process ever reach a point where it stops? Is there only so much carbon that can be converted/sequestered? If conditions change enough, will this huge carbon sink disappear rapidly, adding a HUGE amount of carbon to the atmosphere?
This is fascinating, but it still feels to me like this situation could be as fragile as any others we've discovered around the globe.
Re: (Score:3, Insightful)
I think that this is just an indication that we TRULY do not understand how the global climate actually works. There have been billions of years of fluctuations and change to get the Earth to where it is now. We have no idea how most of that worked and only a vague idea of what is happening now. In the search to figure out why temperatures are rising globally, several things have been named as contributory causative factors. There is NO definitive proof that x, y, or z has caused global warming, only that i
Re:At what point does ythis break down? (Score:4, Insightful)
I think a large part of greenhouse emissions being the blame is people want something they can point their finger at and put it on with the belief there is something they can do to change it.
The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.
Unfortunately, awareness isn't a terribly useful thing especially for the masses. When people learn part of the information, the wrong parts of the whole idea gets heavily associated and then it becomes misinformation.
Ironically, we need less Al Gores and interest groups and treehuggers trying to get 'the word out', we need more university graduates being interested in the study.
Since people can't simply be told there's nothing to worry about yet, they're going for second worst and being fed and recycled the idea that it is everyone's responsibility to ... and that by doing ... it will make things better.
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People want something to save you from (Score:5, Insightful)
Actually, I'm getting the idea that for some people the goal isn't even to point fingers at something, but to point fingers at someone. Subtle but important difference.
Actually, even that is the superficial version. The longer one is that a bunch of people need not just to feel superior to you all, but to be a part of some grand cause that's never done or achievable. The last part is the more important one. It's what makes such grandiose tactually an _easy_ way out.
The quote which comes to mind, and kinda sums it all up, is, "It is easier to be a "humanitarian" than to render your own country its proper due; it is easier to be a "patriot" than to make your community a better place to live in; it is easier to be a "civic leader" than to treat your own family with loving understanding; for the smaller the focus of attention, the harder the task."
So people seek some grandiose cause to fight for, so they don't have to acknowledge that they don't achieve the small ones.
And again, it better be something so grand that nobody actually expects any given individual to achieve anything tangible. In a "small" task, like, say, "I want to finally get out of debt", or "I'll take some lessons and try to find a better job", or "I'll finally have a talk to my son about starting fights at school", there are very clear criteria as to whether you achieved anything or not. And at some point you have to admit that you didn't. It's not a very motivating thought. Worse yet, it might involve some personal effort and change. Good grief.
On the other hand, "saving the world" (from whatever global threat, from MS to global warming to God's wrath) is _easy_. It's a task nobody really expects you to achieve. So you can just moan and bitch a little about how the _other_ people should change, then be smug that you did your part. If it didn't achieve anything, it's because everyone _else_ didn't immediately drop everything and do as you said. Or even if they did, and it didn't actually work, hey, it's still their fault not yours: they didn't do enough, or didn't really understand you.
Big surprise that people choose the latter, eh? They're easy.
And it's not even something new. Since the dawn of time people have got into such grandiose fights to save others from whatever. For a long time, mostly from worshiping the wrong gods, or from worshiping them all wrong, or from some moral/philosophical detail that will doom us all. Mostly because they didn't have some scientific doomsday scenario, so God's Wrath was the best threat they had. Now they can do better.
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Re:At what point does ythis break down? (Score:4, Insightful)
The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.
But you see, we are constantly changing something! We are adding carbon to the carbon cycle of the biosphere, and adding a lot of it, and increasing the carbon release rate. That's a change, and we're doing it, and there's no way we'll stop doing it, so option of "not changing anything" is out. But there is the uncomfortable option of trying to change our planet and biosphere as little as possible...
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it's you who is advocating massive change (Score:5, Insightful)
The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.
But we are changing something: we are emitting CO2 into the atmosphere, and our emissions are growing exponentially. That can't go on: either we stop voluntarily, or we run out of fossil fuel, or we get a climate catastrophe; there simply is no third possibility.
When you are saying that we shouldn't "change anything", you are actually advocating continuing a massive global change, a massive experiment with global climate. People like you are playing word games: you simply redefine what amounts to deliberate and massive change as "no change" by reframing the issue.
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Re: (Score:3, Insightful)
Sod the environmental issues, we need our very-limited fossil fuels for making the various plastics and other common compounds based on simple organic molecules!
Re:At what point does ythis break down? (Score:4, Insightful)
I've often argued that oil is too valuable to use as a fuel (generally), but really, why is it any harder to use coal or algae, or whtever as a plastic feedstock?
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Re:At what point does ythis break down? (Score:5, Insightful)
Depending on how you define "knee jerk", I disagree.
Reducing overall usage of oil is a good thing for many reasons outside of the potential environmental benefits, including:
So, if it's "knee jerk" for the US to ratchet up CAFE requirements (and the equivalents for trucks and trains) so we become best-in-breed at fuel efficient transportation, or for the US to increase investing in alternative energy sources, then I'm all for "knee jerk" reactions.
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Re:At what point does ythis break down? (Score:5, Interesting)
CAFE is just another bureaucratic boondoggle, though it does have the merit that those who can afford larger cars subsidize the purchase of econoboxes.
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The European tax effect (Score:5, Informative)
The problem with CAFE was that it was indeed a boondoggle - the mandated efficiency improvements were actually less than were achieved automatically by European taxation levels, and as you note it was easily evaded with the "light truck" class.
Taxation of fuel is sensible because it is a tax on actual consumption. Most people are able to reduce their consumption by varied means - aggregated journeys, car shares, vacations closer to home, reducing acceleration, using mail order more - without changing their vehicles.
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Re:At what point does ythis break down? (Score:5, Insightful)
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Re:At what point does ythis break down? (Score:5, Insightful)
Well, that's really the problem, isn't it? Knowing what steps to take. Solutions implemented based upon incomplete and politically motivated science may actually make a "problem" worse.
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Re: (Score:3, Funny)
Yeah, lets replace a one dangerous but naturally occurring substance (oil) and replace it with man-made and potentially even more hazardous material (lead acid batteries).
Makes sense to me.
Re:At what point does ythis break down? (Score:5, Insightful)
Do you part for global warming, become a pirate. http://en.wikipedia.org/wiki/Image:FSM_Pirates.png [wikipedia.org]
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Re:At what point does ythis break down? (Score:5, Insightful)
Hansen's data set is skewed to support his theories.
Prove it.
Notice how it doesn't seem to agree with the other temperature records out there.
All of the temperature records disagree with each other to a small extent. The GISTEMP record is not wildly out of line with any of the others, and some of them show slightly more warming than GISTEMP. See here [atmoz.org] for a comparison of the surface records.
Thats because Hansen has built into his system factors for changing the raw data based on his conclusions.
Again, prove it. Hansen has factors to correct for systematic biases in the instrumental observations. ALL the temperature records do (both surface and satellite), although they use different methods to make the corrections. That is quite different from corrections which change the data "based on Hansen's conclusions", which is an accusation of intention and fraud and requires proof.
Try using one of the satellite records where the data hasn't been fiddled with and you get a trend that is very different from what Hansen is predicting,
Actually, you don't. The trends are slightly different, but all within each other's error bars. Here [atmoz.org] is a visual comparison.
Furthermore, the satellite data is "fiddled with" as well. Indeed, the UAH data famously showed recent cooling before they discovered there was a mistake in their error-correction algorithms. Satellite records are by no means objectively superior to the surface station data.
I have no idea where that quote above came from about "Hansen's latest graph", but GISTEMP looks very similar to the other data sets even in the last 10 years; see the above graph.
If the difference between Hansen's numbers and three other temperature records isn't enough to convince you something is screwy with his data then check out all the issues with his temperature stations
If you throw out the temperature stations Watts classifies as "bad", you still get results that are quite close to the GISTEMP record. Or if you throw out the urban stations and only include the rural ones. And finally GISTEMP is quite similar to the satellite records.
There may be station siting issues, but they're clearly not dominating the trend visible in the global temperature time series.
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Re: (Score:3, Interesting)
I've heard one theory (no citation, sorry) that as the solar system moves in alignment with the acretian? disk of the Milky Way this affects solar sunspot activity. That would affect global climate. The thought was changes in space radiation hitting the sun affects it's activity, much as radiation is believed to cause lighting in storms. It's a theory, and sounds plausible. There just is no evidence as yet as to whether this is true and how much it would affect global climate.. The Sun has been quiet lately
Re:At what point does ythis break down? (Score:5, Insightful)
(a) that there have been times in the past with wayyy higher CO2 concentrations and
Yes, and it would have been pretty unpleasant for human beings had we been around at the time.
(b) that historically CO2 raises happen *after* temperature raises and
Yep, which just goes to show that if CO2 also causes temperature rises (pretty fairly conclusive that it does), that we'll end up in a rather painful positive feedback loop (CO2 goes up, causing temperature to go up, which causes CO2 to go up more)
(c) some of the measured temperature rise (of course, you are suitably sceptical about those measurements as well, aren't you?) can be explained by the fact we're coming out of an ice age and
I think that's pretty well accepted also, but historically there's nothing similar to what's happening now - we're rising MUCH faster than we should be.
(d) the fact that the Earth is neither a boiling Hellhole nor a ball of ice suggests that fairly effective negative feedback is at work in the climate?
No, that suggests that the Earth is (surprise surprise) a pretty good place for people to live in general. The concern is that it may not stay that way.
The concern is not that temperature is rising - that happens. It rises, it falls - there are perfectly normal cycles to all of this, and as long as we can learn to understand it, we can learn to live with it. What the concern IS is that we appear to be having an effect on our climate and we don't understand enough about what we're doing to it. It currently appears as if our effect is speeding up the "natural" warming quite significantly, and we're having a very hard time trying to figure out what the consequences of this will be. Maybe our effects will be nullified by natural processes and we can just carry on, but maybe they won't be and we'll end up killing ourselves (or just making life extremely unpleasant).
Because we're sitting here at "don't know", we have the choice of either ignoring the situation or trying to do something about it. I UNDERSTAND the arguments for both, but I don't agree with the argument for doing nothing.
The argument for doing nothing basically says, "well, we don't understand it, and doing something could cause economic problems. Because we don't understand it, we can't necessarily do anything about it.".
The argument for doing something goes, "We don't understand it, but we are certain that we are having an impact of some kind, and that has the potential to be very bad (it also has the potential to not be bad, but we're pretty sure it will be bad, and we don't want to take the gamble). So, what we'll do is try to reduce the factors that cause our effect."
We may not completely understand our climate, but:
1) We CAN see we're having an influence on it
2) We aren't 100% certain, but are pretty sure that our influence on it will cause long term bad effects
3) We are quite confident we know the cause of our effect on the climate (CO2 amongst many other things)
Because of this, the sensible choice seems to be "let's try to reduce or negate the effect we're having on the environment, because we can't be sure if that effect is going to cause us serious problems or not".
Car analogy time: I know very little about cars, and have to rely on what others tell me. I'm driving my car, and the oil light comes on. I recently changed the oil, and I haven't noticed any leaks, although honestly I wasn't paying much attention before now. My passenger suggests that maybe it's just that a circuit going to the oil light indicator is shorted somewhere, which is why it's showing that, and I really needn't worry - my car will be fine. Now, I can not be certain if he's right or wrong without investigation. So, I take my car to a mechanic, who checks only the circuitry going to the light. He says it's okay. At this point, I can choose to continue driving my car, thinking the mechanic missed something and it really is just a problem with the light, or I can ask the mechanic to check the oil system, even though I know there's going to be a larger financial cost involved in doing so. What should I do?
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Something is not quite right here... (Score:5, Insightful)
If this is indeed the case it would seem a bit strange that it has not been detected before. I mean with all the climate change debate going on there has been quite close scrutiny of the estimates of CO2 going into and out of the atmosphere, so if this is as big a carbon sink as described it would have to mean that the other sinks ( i.e the ocean and the biosphere ) are less potent than previously assumed.
Re:Something is not quite right here... (Score:5, Funny)
You'd think that exactly what you're looking for wouldn't be right in front of you until you find it is.
Now, where the Hell are my keys...
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Re: (Score:3)
Probably not detected because it's been assumed all along that desert chemistry is fairly static, due to the general lack of "input" from the usual reactives, ie. water and biomass. So... I'd guess no one ever actually LOOKED.
Ooops... now, what other assumptions about climate, and climate change, might be completely broken??
Misleading Summary (Score:5, Informative)
The effect could be huge: About 35% of Earth's land surface, or 5.2 billion hectares, is desert and semiarid ecosystems. If the Mojave readings represent an average CO2 uptake, then deserts and semiarid regions may be absorbing up to 5.2 billion tons of carbon a year.
Also...
For now, some experts doubt that the world's most barren ecosystems are the longsought missing carbon sink. "I'd be hugely surprised if this were the missing sink. If deserts are taking up a lot of carbon, it ought to be obvious," says William Schlesinger, a biogeochemist at the Cary Institute of Ecosystem Studies in Millbrook, New York, who in the 1980s was among the first to examine carbon flux in deserts. Nevertheless, he says, both sets of findings are intriguing and "must be followed up." Scientists have long struggled to balance Earth's carbon books. While atmospheric CO2 levels are rising rapidly, our planet absorbs more CO2 than can be accounted for.
and...
Provided the surprising CO2 sink in the deserts is not a mirage, it may yet prove ephemeral. "We don't want to say that these ecosystems will continue to gain carbon at this rate forever," Wohlfahrt says. The unexpected CO2 absorption may be due to a recent uptick in precipitation in many deserts that has fueled a visible surge in vegetation. If average annual rainfall levels in those deserts were to abate, that could release the stored carbon and lead to a more rapid buildup of atmospheric CO2--and possibly accelerate global warming.
This is not, as some posters are implying, published science that concludes the IPCC predictions are in any way likely to be inaccurate, or that carbon is accumulating in the atmosphere at a rate lower than previously thought.
This is a news article in science detailing some interesting research showing that deserts may be absorbing more carbon than was previously thought, and that this may account for the fact that atmospheric measurements show the earth is absorbing carbon at a higher rate than can be accounted for by currently known sinks. The amount of CO2 in the atmosphere is known from atmospheric measurements, and is higher than at any time in the last 650,000 years.
Re:PDF (Score:5, Insightful)
It is called the status bar. It shows you what a link is pointing to.
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Re:Create more deserts? (Score:4, Insightful)
How about we say the deserts allow the earth's thermal system to reach a balance? We have more deserts, which sequester more carbon, which makes us cooler, which sequesters less carbon, which makes us hotter, which makes more deserts.
We shouldn't worry about global warming, we should worry if we can survive global warming...
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Re: (Score:3, Insightful)
You need to think that through a little deeper, nothing in this discovery changes existing observations of the upward trend in GHG concentrations, nor does it change the observed temprature trends, nor suddenly refreeze the Artic, reverse the melting of glaciers, fill the dams of SW Australia, restore the oceans ph balance, etc, etc.
There is nothing wrong with being skeptical but be aware that skepticisim is a s [wikipedia.org]
Re: (Score:3, Insightful)
Unless you are skeptical of global warming. Then you will be compared to Holocaust deniers and threatened with losing your academic funding and credentials.
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Re:Sooo... (Score:5, Informative)
No, the prolific amount of oil in the Middle East is mainly related to organic carbon [wikipedia.org] in source rock [wikipedia.org] deposits that formed in the marine environment. The source rocks in the Middle East are particularly widespread and productive.
The article is talking about carbonate [wikipedia.org] (i.e. minerals with CO3 in their structure), which is completely different and is often referred to as "inorganic carbon". It's as different as algae (organic carbon) and sea shells (carbonate). They both involve carbon and both can have biological origins, but you can't generate oil from carbonate. You need molecules with plenty of H and C for that (i.e. hydrocarbon molecules).
You can, however, find holes in carbonate rocks. In the right setting these can contain oil that has migrated into the porous rock from organic-rich source rocks nearby. Such rocks are known as petroleum reservoirs. Again, the Middle East has some spectacular reservoirs with very high porosity and permeability, allowing for plenty of space to hold the oil and to allow it to flow out. For example, the Ghawar field [wikipedia.org], which is the biggest oil field in Saudi Arabia and the world, has limestone reservoirs with up to 35% porosity by volume -- i.e. 35% of the volume isn't rock, but open spaces filled with fluid (either oil, gas, or water). That's extraordinarily high porosity. It's full of holes like a sponge.
So, if you want the short answer to why there is so much oil in the Middle East: 1) spectacularly prolific and widespread organic-carbon-rich source rocks, 2) highly porous and permeable reservoir rocks (some of which are carbonates, some of which are other rock types), and 3) large "trap" structures, which I haven't discussed, but basically refers to the geometry of the porous reservoir and an impermeable seal that keeps the oil/gas from leaking out.
It has very little to do with the modern deserts that are widespread in that part of the world today. Many of the conditions necessary for the large oil deposits were set up far enough back in geological history that today's climate is mostly irrelevant.
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Re: (Score:3, Funny)
I was trying to be funny, but obviously failing
Re: (Score:3, Funny)
If the climate change is actually a natural process then the attempt to control it has become our first great terraforming project. How convenient that we're trying this on the only planet we have and not some spare planet that wouldn't matter if it went awry.
And if the rapid climate change is not a natural process then we have already not just attempted but are in the middle of an effective terraforming project where the only definition of 'success' must be some form of 'not at all like what we had before'. That sounds much worse to me than your what-if.
The environmental people are either saying:
1) our climate is changing, lets make it like it's always been before
-or-
2) we've changed our climate to something different and unknown, lets change it back again.
Eit
Re:Fragile Earth or Robust Earth? (Score:5, Informative)
Indeed? Then I'd like to see your figures. Because we outdo the volcanoes by a factor of a hundred [wikipedia.org]. Looking into other sources, well: rotting vegetation was mentioned, and I agree it's a far larger quantity than human activity, but is that a source of carbon dioxide? Rotting vegetation can never release more carbon dioxide than the amount it absorbed when it first grew, making it net carbon neutral. Unless there is a net decrease in the planet's biomass, there's no overall extra carbon dioxide in the atmosphere due to plant life. Same goes for respiration by living things: the CO2 I exhale is carbon that was absorbed when my food grew, and will be absorbed again as a future meal grows.
We on the other hand are digging up and releasing vast quantities of carbon dioxide, all year, every year, and unlike the plants we're not taking it back out of the atmosphere. That's producing an ongoing year-on-year net increase in carbon dioxide. Nothing else on earth compares to human industry for increasing atmospheric CO2 concentrations.
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