I first became aware of weather as a political factor while a college student. As a history major,  I studied the French Revolution, largely caused  by a drought that ruined grain harvests in France the years just before it began in 1789. Prior to that, I learned of the very cold 18th century winters that froze the Thames in London and forced George Washington to battle ice floes as he crossed the Delaware RIver on Christmas Eve 1776 on his way to defeat the Hessians at Trenton. I soon learned that these atmospheric conditions were caused by what has come to be known as the Little Ice Age. Climate scientists have now counted 18 such Little Ice Ages and are now describing the onset of the 19th. Click the link below to read the details -Keep Warm.

http://business.financialpost.com/fp-comment/lawrence-solomon-global-warming-doomsayers-take-note-earths-19th-little-ice-age-has-begun