Cooling off in a warmer world?

Well I'm not a denier, and I'm too lazy (actually busy) to find a good reference for you, but here's one scenario. Nobody really knows for sure what's going to happen with El Nino/La Nina frequency under global warming. It may turn out that global warming increases the frequency of El Ninos, or of La Ninas, or even of both (that is, less neutral states). If the frequency of La Ninas increases, then yes, some areas may experience cooling which is "due to" global warming. We just don't know yet, El Ninos and La Ninas are not that accurately predictable right now.