Nightly News | January 04, 2013
>>> we've done a lot of reporting lately about the drought that's left much of this nation way too dry. tonight there's some potentially good news to report in a part of the west where an early flurry of winter snow may be a welcome sign for the water supply . nbc's miguel almaguer reports from california , sierra nevada mountains .
>> reporter: in the mountains of california 's gold country , this season, a different kind of boom.
>> the amount of snow pack determines how much water we're going to have next summer.
>> reporter: the sierra nevada snow pack sits at 134% of normal. early snowstorms have dumped half a typical winter's snowfall in just two weeks.
>> that's a huge turnaround from last year.
>> reporter: the change in just 12 months is dramatic. last year on this day in squau valley. this year. but chris field and his team who won a nobel prize for their work on climate change warn snow is melting faster than ever before.
>> we have been seeing earlier snow melt , and we have been seeing this in a consistent way, and it's something we expect to continue as the climate warms.
>> reporter: for now, reservoirs are filling fast, a lifeline for the nation's largest agriculture-producing state, which uses 75% of its water for irrigation. the snow pack here in the california sierras should help ease a drought that's crippled this area. but while there's plenty of powder here, there is troubling signs elsewhere. in colorado and wyoming, the snow pack is 15% below normal. 60% of the country remains in drought.
>> it's almost certain that 2012 will be the warmest year in the instrumental record, and the combination of the high temperatures with the variability that you get from random, chaotic parts of the climate system really set us up for the kinds of extremes that we're seeing.
>> reporter: right now, they like what they see in snow country . but to make a real difference, more steady powder must fall here for the next three months. miguel almaguer, nbc news, along the california sierra nevada .