ScienceNow: Climate scientists have painted an unpleasant picture of the end of this century if humankind keeps spewing climate-changing gases into the atmosphere. Now they are pointing out that the ill effects won't be going away for a long, long time. The carbon dioxide we're emitting this century is so slow to disappear and climate so slow to respond, they say, that the effects felt in a century or two will be almost as strong 1000 years from now.