Lemonick thinks most of us are worried about the atmosphere containing CO2 (0.04%) and [gasp] natural gas (0.0002%). Not the sort of “bomb” that would keep many awake at night I suspect.
Most of the worry over greenhouse gases centers on carbon dioxide, and rightly so: thanks mostly to the burning of fossil fuels, levels of this heat-trapping pollutant have soared to nearly 400 parts per million in the atmosphere, far above the 270 ppm that prevailed before 1800 or so, and they’re still rising — triggering a rise in sea level, temperature, and other telltale signs of climate change.
But CO2 isn’t the only greenhouse gas: methane traps heat too, and it’s a lot more powerful, molecule for molecule, than carbon dioxide. The good news is that there’s much less methane up there than CO2. The bad news: global warming could release vast natural deposits of methane trapped in the Arctic, making the temperature increase we’re already seeing go into overdrive.
No one knows if and when that might happen, but even the mere possibility has galvanized scientists into pondering what they could possibly do about it should the worst come to pass — and a paper in Environmental Science & Technology is the latest and most comprehensive assault on the problem yet.


