Anyone who reads the news knows that global warming is going to kill us all. But did you know that, before you die, you are going to be really, really itchy?

Another reason to worry about global warming: more and itchier poison ivy. The noxious vine grows faster and bigger as carbon dioxide levels in the atmosphere rise, researchers report Monday. And a CO2-driven vine also produces more of its rash-causing chemical, urushiol, conclude experiments conducted in a forest at Duke University where scientists increased carbon-dioxide levels to those expected in 2050. Carbon dioxide is a greenhouse gas – a chemical that traps heat similar to the way a greenhouse does – that’s considered a major contributor to global warming. Greenhouse gases have been steadily increasing in the atmosphere since the Industrial Revolution.

Amy Ridenour writes, “I’ve often read that plants grow better when exposed to higher concentrations of carbon dioxide.” Should we be at all surprised by this study, given that plants, by definition, convert CO2 into food?

On a more serious note (or perhaps less serious, as it involves Paul Krugman), Jason Steorts has written a great rebuttal to critics of his cover story on the global warming debate.