Posted on 06/11/2014 3:15:09 PM PDT by Up Yours Marxists
There have been times in our geological history when CO2 levels were 10X what they are today, yet warming was only slightly higher.
Unlike what you often read in simplistic media accounts, there are a lot of variables in climate and weather and temperature. It takes a lot of things going wrong to turn Earth into Venus and we have never come close.
At the Goldschmidt geochemistry conference in Sacramento, geochemists discussed one such period, but they say we just got lucky - a vast mountain range formed in the middle of the ancient supercontinent, Pangea.
Around 300 million years ago, plate tectonics caused the continents to aggregate into a giant supercontinent. The sheer size of the continent meant that much of the land surface was far from the sea, and so the continent became increasingly arid due to lack of humidity. This aridity meant that rock weathering was reduced; normally, a reduction in rock weathering means that CO2 levels rise, yet in spite of this CO2 levels which had been falling prior to the mountain formation- continued to drop, eventually undergoing the most significant drop in atmospheric CO2 of the last 500 million years. This phenomenon has remained unexplained - and still is, but a group of French scientists from the CNRS in Toulouse have come up with a conjecture based on a model which seeks to explain this contradiction.
(Excerpt) Read more at science20.com ...
The article fits very well with the likelihood that the rise of the Himalayas together with the Monsoon rain patterns resulted a big carbon sink. The all time low CO2 levels may have been one of a number of factors leading to the ice ages.
Great screenname! LOL!
The article appears to be deeply flawed by disregarding the role of the positioning of the supercontinent astride the tropical belt at the the same time the shallow Tethys Sea promoted increased plant growth, the Devonian and Carboniferous forests developed and dramatically increased the atmospheric concentrations of Oxygen by equally dramatic depletion Carbon dioxide, the increased Oxygen concentrations lowered atmospheric temperatures, and the lowered atmospheric temperatures removed Carbon dioxide from the atmosphere and kept it dissolved in the hydrosphere. Similar cycles can be seen every time the Earth’s temperatures have become cold the atmospheric concentrations of Carbon dioxide have dramatically declined.
A little mix of God deriving the function that we discovered as mathematics. The rest is physics.
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