Wikipedia says we are still in an ice age as long as Antarctica and Greenland are covered with ice. So when will the ice come grinding back?
Within 2,000 years, says this professor.
Now, carbon levels are approaching 400 ppmv as the burning of fossil fuels pumps more and more carbon dioxide into the atmosphere. Even if the rate of growth could be moderated enough to stabilize levels at about 550 ppmv, average temperatures might well rise by about 5 oC–with devastating effects for us earthlings, such as rising sea levels and dramatic changes in weather patterns.
But even that warming will not stave off the eventual return of huge glaciers, because ice ages last for millennia and fossil fuels will not.In about 300 years, all available fossil fuels may well have been consumed.Over the following centuries, excess carbon dioxide will naturally dissolve into the oceans or get trapped by the formation of carbonate minerals. Such processes won’t be offset by the industrial emissions we see today, and atmospheric carbon dioxide will slowly decline toward preindustrial levels. In about 2,000 years, when the types of planetary motions that can induce polar cooling start to coincide again, the current warming trend will be a distant memory.
Professor Franklin Hadley Cocks ‘63, SM ‘64, ScD ‘65, teaches energy technology and climate-related courses at Duke University and is the author of Energy Demand and Climate Change (Wiley-VCH), which summarizes energy and climate issues of the past, present, and future.
As I gaze out my windonw at this winter’s worst snow storm, I long for the annual warming trend called spring.