The Economic Effect of Climate

insects, allowing Philadelphia to recover. If weather could be the key to a city's fortunes, Masters thought, then why not to historical fortunes of nations? And could frost lie at the heart of one of the most enduring economic mysteries of all - why are almost all the wealthy, industrialized nations to be found where the climate is cooler? B After two years of research, he thinks that he has found a piece of the puzzle. Masters, an agricultural economist from Purdue University in Indiana, and Margaret McMillan at Tufts University, Boston, show that annual frosts are among the factors that distinguish rich nations from poor ones. Their study is published this month in the Journal of Economic Growth. The pair speculate that cold snaps have two main benefits - they freeze pests that would otherwise destroy crops, and also freeze organisms, such as those carried by mosquitoes, that carry disease. The result is agricultural abundance and a big workforce.