Over the past 16 years, the ski season has been steadily shrinking -- despite the fact resorts dramatically have improved their snowmaking, expanding it over a wider area and investing in technology that allows them to make snow at warmer temperatures. But according to the National Ski Areas Association, Western ski resorts have been losing nearly a day of skiing a year since 1990. Whether you call it global warming or climate change, warming temperatures -- last week's cold snap notwithstanding -- are having a serious long-range effect on skiing.