As the planet warms, winter is shrinking. In the last fifty years, the Northern Hemisphere lost a million square miles of spring snowpack, and high-elevation snowpacks in the western United States have decreased by nearly half since 1982. On average, winter has shrunk by a month in most northern latitudes.In this deeply researched, beautifully written, and adventure-filled book, journalist Porter Fox travels along the edge of the Northern Hemisphere''s snow line to track the scope of this drastic change and how it will literally change everything-from rapid sea level rise, to fresh water scarcity for two billion people, to massive greenhouse gas emissions from thawing permafrost, and several climate tipping points that could very well spell the end of our world.This original research is animated by four harrowing and illuminating journeys-each grounded by interviews with idiosyncratic, charismatic experts in their respective fields and Fox''s own narrative of growing up on a remote isl