Cool the Climate Alarmism

The latest U.N. forecast should remind us that the climate is an immensely complex system.

The report released before last year’s climate conference points to global warming of between two and three degrees centigrade over pre-industrial levels, considerably less than the increase of four or even five degrees that was once widely forecast.

We cannot pretend to be certain what it will look like at the end of the century, or how much of any change will be due to human activity, or what the effects of climate change will be. We do know...