Historical warnings of future food insecurity with unprecedented seasonal heat.

Using data from global climate models, Battisti and Naylor demonstrate that if global warming is unchecked, the hottest summers we've experienced in the recent past will be the norm in the future, to the detriment of agricultural productivity world-wide. This is an exceptional article because the authors provide concrete and palpable illustrations of what the world will look and feel like if we do not reverse global warming.

How hot will it be at the end of the century if human activities continue to warm the Earth? What will it feel like in the future and how will elevated temperatures affect our ability to feed ourselves? In their article, Battisti and Naylor answer these questions in a very direct and tangible manner. The bottom line - if we fail to control the accumulation of greenhouse gases in the atmosphere, the average temperatures that our children will experience toward the end of the century will be equivalent to the hottest temperatures we experience today. The authors use historical examples to illustrate the consequences of unchecked heating for society. The examples are unnerving. Remember the heat wave in France in 2003, the one during the Tour de France? Mean summer temperature was just 3.6C above the long term average. Over 30,000 people perished from heat, livestock became severely stressed, and agricultural production of fruits and grains decreased by over 20%. It is incumbent on our new administration to work with world leaders to dramatically reduce the accumulation of greenhouse gases in the atmosphere. "Cooler" heads must prevail.