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A Hidden Loop In the Carbon Cycle Discovered
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."
The solution is obviously to cut down more trees and make more deserts, right?
Does this mean that all the salinization that has been going due to irrigation because america grows FRUIT in the desert is actually a good thing?
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...
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.
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It is called the status bar. It shows you what a link is pointing to.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
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.
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...
Forests soak up a lot of carbon, but then drop a lot of leaves. When the leaves rot they give off CO2 and methane. Methane is far worse as a green house gas than CO2 - by a factor of over 20.
Engineering is the art of compromise.
"Each year, the Rainforest is responsible for over three thousand deaths from accidents, attacks or illnesses." - Rainforest Schmainforest and now forests are rotting and giving off greenhouse gases. We must act to stop these forests from further encroaching upon our Earth-friendly deserts, it is time we cleaned them up.
No, the prolific amount of oil in the Middle East is mainly related to organic carbon in source rock 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 (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, 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.
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.
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.
A polar bear is a cartesian bear after a coordinate transform.
Unless you are skeptical of global warming. Then you will be compared to Holocaust deniers and threatened with losing your academic funding and credentials.
3 things about computers: they're alive, they're self-aware, and they hate your guts.
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.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Good points. Interestingly there is a lot of Methane bubbling out of the melting permafrost, particularly in E. Siberia. However the last two IPCC forecasts for increased Methane concentrations have failed to materialize, ie: levels have remained relatively stable for a decade after a steadily rising trend a few decades long. I consider the "missing methane" and "collapse of the Artic sea ice" to be the two biggest errors in the IPCC forecasts.
Just a thought but perhaps this new discovery is connected to the "missing methane"?
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
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.
...temperatures from 1961 to 1990...We in the Northwestern hemisphere have experienced 7 of the top 8 warmest years on record since 2001, and all 10 top warmest years since 1995.
So...you know that the Earth as a whole has been cooling since 1998, right?
One last thing: Sometimes I wonder; "Is that someone's signature? Or do they type that at the end of each post?"
You've obviously never been in the same room as me! :)
Glad you noticed that the errors I chose support different conclusions by different un-scientific groups. An error is an error regardless of which conclusion it supports. Errors do make a model less reliable but they certainly don't make them useless ( as can be witnessed by everyday interaction with the internet ).
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.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
I've afraid you're the one whose bought into a common lie. Human activity releases far, far less carbon dioxide than the planet produces. We are minuscule in the big picture, nothing but ants.
Indeed? Then I'd like to see your figures. Because we outdo the volcanoes by a factor of a hundred. 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.
Real Daleks don't climb stairs - they level the building.
"Meanwhile, the Antarctic ice is growing."
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.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.