If the excesses of the holidays get you down, you're not going to like the modeling results that Canadian climate researchers are reporting this week in Nature Geoscience. It looks like the carbon dioxide cocktail we are brewing in the atmosphere will leave us with a hangover that won't quit.
Scientists have been warning for some time now that, because CO2 lives so long in the air, its impact on global temperatures will be felt long after we curb the emissions of fossil fuels, which most researchers see as the cause of global warming.
It is a prospect that is almost too gloomy to contemplate. Once in the atmosphere, CO2 stays up there for many centuries, scientists say. Some of it begins mixing with the ocean or the land vegetation after a few hundred years, and some of it stays up there practically forever. Climate specialists use phrases like "irreversible on human timescales" to describe our predicament.
An international team of researchers reported two years ago in the Proceedings of the National Academy of Sciences that "the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop." On a global scale, "atmospheric temperatures do not drop significantly" for a millennium.