Scientific American: Dear EarthTalk: Don’t all these huge snow and ice storms across the country mean that the globe isn’t really warming? I’ve never seen such a winter! — Mark Franklin, Helena, MT On the surface it certainly can appear that way. But just because some of us are suffering through a particularly cold and snowy winter doesn’t refute the fact that the globe is warming as we continue to pump carbon dioxide and other greenhouse gases into the atmosphere. According to the National …