Some years ago, climatologist Michael Mann published a study that led to the hockey stick graph that showed that the Earth’s overall temperature spiked in the last century.
Now, a new study shows that this spike in temperatures is unprecedented going back more than a hundred centuries. The rate of global warming now is much faster than it ever has been up to 11,300 years ago. In fact, during the last 5000 years, the Earth cooled by about 1.3°F. In the last 100 years, our temperature spiked upwards by about the same amount.
And that’s not the worst news. At Think Progress, Joe Romm took these predictions from climatological literature and projected them into the near future resulting in an ~8° F rise. We’re pumping 30 billion tons of CO2 into the atmosphere every year—more than 100 times as much as all volcanoes combined—and that massive amount of carbon dioxide is upsetting the heat balance in our atmosphere.
However, the Climate Change Deniers respond that there have been much greater fluxuations over the history of the Earth. That’s true. The relatively new field of Paleoclimatology projects much wider variations, as can be seen from this pretty standard chart.
However, far from the implications that the Climate Change Deniers draw, the fact of these much larger fluxuations actually makes our situation much more dangerous.
During the 10,000 years of human civilization, temperatures on Earth have been quite cool and stable. Throughout most of Earth’s history negative and positive feedback loops have led to rapid extreme variations in temperature.
According to Robert M. Hazen in The Story of Earth, “with each episode of (snowball-hothouse) climate reversal, almost every living thing died…If greenhouse gas concentrations rise too rapidly, no known mechanisms can absorb the excess. Will warming trigger a massive methane release, with all the positive feedbacks that that scenario might entail? Will sea level quickly rise hundreds of feet, as it has so many times in the past? Have we reached the tipping point? Probably not (yet)…but that’s the thing about tipping points – you can never be sure you’re at one until it’s happened.”
Sea level rise of hundreds of feet really isn’t in anyone’s interest. Doesn’t it seem wiser to take whatever steps are necessary to stay within the narrow temperature limits that are necessary for our civilization to survive?