FRESNO -- Farmers and water officials throughout California wait each year for forecasts about snowmelt roaring down the Sierra's granite canyons -- precious water for the long summer. But the forecasts are only estimates based on averages of past seasons, snow-sensor readings and monthly measurements from mountain meadows above big rivers. The forecast can be wrong, leaving farmers with too much or too little water in the growing season. One big reason: Nobody measures snow around jagged ridges, plunging ravines and deep forests in the 400-mile-long Sierra. That's a huge swath of the high country where the size of the snowpack is unknown Read more here: http://www.modbee.com/2010/04/19/1134283/scientists-seek-better-way-to.html#storylink=cpy