NASA on Global Warming

Despite supposedly clever quips by "climatologists" like Glenn Beck and Rush Limbaugh, the cold snaps of late don't negate the rising AVERAGE temperature of Planet Earth. Since the sun's output has been low the last 20 years, and since variations in the Earth's orbit and axis that can naturally warm the planet are not in play, it seems clear to me the cause is the HUGE increase in atmospheric CO2 and methane added by humankind since 1750. John

http://www.nasa.gov/vision/earth/lookingatearth/earth_warm.html