I asked in a previous post what was keeping America's chief climate scientist up at night. One answer was a set of readings that show suddenly accelerating carbon dioxide concentrations in the atmosphere. Such readings could mean we may be nearing a point at which global warming would become self-reinforcing and therefore not amenable to anything we do to stop it.
Now there's another development that is increasing concern about runaway global warming. It's called "methane burps." Huge stores of methane lie frozen beneath the arctic tundra. That tundra is warming quickly and could begin releasing its methane, a greenhouse gas that is 20 times more effective than carbon dioxide at retaining heat inside the earth's atmosphere.
As the methane leaks and causes temperatures worldwide to increase, it would also lead to further releases of methane in a spiral that would be far more catastrophic than anything yet predicted.
Pure fantasy? The geologic record shows that it's happened before with devastating effects for nearly all life.
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