The time scale should stagger you. Just imagine for a moment that what we humans do on this planet will last at least 10,000 more years, and no, I’m not talking about those statues on Easter Island or the pyramids or the Great Wall of China or the Empire State Building. I’m not talking about any of our monumental architectural-cum-artistic achievements. Ten thousand years from now all the monuments to our history may be forgotten ruins or simply obliterated, while what we’re doing at this very moment that’s truly ruinous may outlast us all. I’m thinking, of course, about the burning of fossil fuels and the sending of carbon dioxide (and other greenhouse gases) into the atmosphere. It’s becoming clearer by the month that, if not brought under control relatively quickly, this process will alter the global environment in ways that will affect humanity and everything else living on this planet for what, from a human point of view, is eternity.
In essence, there’s no backsies when it comes to climate change. Once you’ve begun the full-scale destabilization and melting of the Greenland ice sheet and of the vast ice sheets in the Antarctic, for instance, the future inundation of coastal areas, including many of humanity’s major cities, is a foregone conclusion somewhere down the line. In fact, a recent study, published in the journal Nature Climate Change by 22 climate scientists, suggests that when it comes to the melting of ice sheets and the rise of seas and oceans, we’re not just talking about how life will be changed on Planet Earth in 2100 or even 2200. We’re potentially talking about what it will be like in 12,200, an expanse of time twice as long as human history to date. So many thousands of years are hard even to fathom, but as the study points out, “A considerable fraction of the carbon emitted to date and in the next 100 years will remain in the atmosphere for tens to hundreds of thousands of years.” The essence of the report, as Chris Mooney wrote in the Washington Post, is this: “In 10,000 years, if we totally let it rip, the planet could ultimately be an astonishing 7 degrees Celsius warmer on average and feature seas 52 meters (170 feet) higher than they are now.”
Even far more modest temperature changes like the two degree Celsius rise discussed at the recent Paris meeting, where 196 nations signed onto a climate change agreement, would transform the face of the planet for thousands of years and result in the drowning of a range of iconic global cities “including New York, London, Rio de Janeiro, Cairo, Calcutta, Jakarta, and Shanghai.”