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Here's a bit of good news about climate change:
One climate doomsday scenario can be downgraded, new research suggests.
Decades of atmospheric measurements from a site in northern Alaska show that rapidly rising temperatures there have not significantly increased methane emissions from the neighboring permafrost-covered landscape, researchers reported December 15 at the American Geophysical Union's fall meeting.
Some scientists feared that Arctic warming would unleash large amounts of methane, a potent greenhouse gas, into the atmosphere, worsening global warming. "The ticking time bomb of methane has clearly not manifested itself yet," said study coauthor Colm Sweeney, an atmospheric scientist at the University of Colorado Boulder. Emissions of carbon dioxide — a less potent greenhouse gas — did increase over that period, the researchers found.
Some have been concerned about a sudden, runaway spike in greenhouse gases owing to thawing methane clathrates in the ocean (the "Clathrate gun hypothesis") and in the permafrost.
(Score: 5, Informative) by Immerman on Wednesday December 21 2016, @03:51AM
Umm, not quite. Heat capacity (specific heat) is an independent concept from greenhouse gases - in fact, (all else being equal) increasing the specific heat of the atmosphere would actually cool down the atmosphere, since the same amount of heat would be stored at a lower temperature.
What makes something a greenhouse gas is not how much heat it stores itself, but how much infrared radiation it reflects - basically it slows down how fast the planet can shed heat into space. Heat is arriving at a constant rate from the sun, so if we slow down the rate at which it leaves, excess heat will build up. Sort of like wrapping the whole planet in a mylar "space blanket".
Oxygen, nitrogen, and most other gasses in the atmosphere are basically transparent to infrared light, if they were the only gasses in the atmosphere then the heat radiated as infrared light from the ground would head straight out into space unimpeded, and the planet would be a frozen wasteland.
However, water vapor, CO2, methane, and other greenhouse gasses all have absorption/emission lines in the thermal infrared spectrum (a property of their quantum electron excitability energies, rather than the mechanical properties of their bonds), which means they will absorb infrared photons being radiated from the ground and then re-emit them in a random direction, roughly half of which are back towards the ground. The more greenhouse gasses in the atmosphere, the longer the photons will bounce around, and the better the chance that they'll end up coming back down to re-heat the ground rather than escaping into space.