
http://www.mnn.com/
As you can see in the picture above, the tropics are expanding – just as climate scientists forecast.
But suppose that actually did happen? What would the effect be? A primary response would be that CO2 would contribute less to the greenhouse effect. In the tropics, almost all of the LW radiation is absorbed by water vapour and clouds. The high humidity makes CO2 almost irrelevant.

http://www.globalwarmingart.com/wiki/File:Atmospheric_Transmission_png
Similarly, polar warming would lead to higher humidity and reduced importance of CO2 as a greenhouse gas. Good thing for alarmists that Antarctica is cooling.