"Greater historical perspective is needed to enlighten current debate about future human responses to higher temperatures and increased precipitation variation. We analyze the impact of climatic conditions and variability on agricultural production in five semi-arid western states. We assemble...

"Reducing emissions of the greenhouse gases that cause climate change will require dramatic changes in the way that energy is produced and consumed. The cost of technological changes such as alternative energy sources and improved energy efficiency will play a large role in determining the...