“You are trying to understand what’s happening all over the world in one value,” says Torres. Torres admits that the methodology isn’t perfect. Extrapolating data from a single place to an entire planet and an incredible timespan is something of a necessity, because the earth’s chemistry is not something you can easily measure in laboratory-sized chunks. That was enough to convince them that the forces that churn the earth’s crust into jagged peaks also help our climate stay relatively stable in between catastrophes-such as meteor impacts, solar storms, and industrial revolutions. The researchers extrapolated the numbers from the literature to a global sulphur estimate, taken from 65-million-year-old chemical signatures found in marine rocks. Although the area they measured accounts for barely 2% of the globe’s land, their estimates showed that it was the source of 40% of the world’s mineral-derived sulphur. Back in California, Torres found river runoff data for four other young mountain zones that had abundant pyrite. Torres and his co-authors first suspected that they could on a field trip in South America, when mineral data from the Andes contrasted sharply with that from the Amazonian lowlands. However, nobody before thought that mountains could be shedding enough pyrite to stave off a massive carbon deficit.
IRON MARINES BEAM ME UP SCOTTY CRACK
This is known to crack the bonds carbon forms with other non-organic minerals (like calcium), so that the carbon escapes into the atmosphere as CO2. When it’s weathered away from the mountain and exposed to oxygen, it releases sulphur dioxide. Pyrite, or iron sulfide, also known as fool’s gold, is a deep-earth metallic mineral that gets thrust to the surface when mountains rise. The answer, says Mark Torres, the paper’s lead author, is in the stone. Even volcanoes, which belch carbon into the air, would not be enough to offset its relentless sequestration into the deep oceans.
Scientists know of some feedback mechanisms that could have slowed the cooling, but these on their own don’t explain our climate’s long-held stability. “If it weren’t for feedback mechanisms, it would only take 5-10 million years to screw things up,” Derry says. Too much CO2 contributes to global warming, but too little would have made the earth a much colder place, preventing life from developing. Louis Derry, a geochemist from New York’s Cornell University (who was unaffiliated with the study) says this process should have sucked the carbon dioxide out of the atmosphere eons ago.
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