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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?
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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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.
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.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
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.