SEATTLE - Turn on your water, and evidence of climate change will flow out of the faucet. At least that's the case according to Seattle Mayor Greg Nickels.

The mayor's claim is based on the city's measurement of the just how much water the winter snow pack yields each year.

To find out, researchers travel miles from Seattle and touch down in a winter landscape that serves as an oracle of the summer to come. Snow covers 90,000 acres of the land up in the mountains of western Washington, quenching the thirst of the city's residents.

But the mayor says someday the snow pack may not be enough.

Just a few years ago, the city was hit with a water crisis. When scientists measured snow pack, the mountains held only a quarter of the water Seattle needed for the summer. Mayor Nickels blames the climate change.

"2004 to 2005 was the tough one for me, that was the 'ah-hah moment' for climate change," Nickels said.

But the upcoming summer isn't expected to be as dry. Tom Fox with Seattle Water Management says things are looking up this year.

"Right now we have 110 percent of average snow for this time of year," he said.

But this year's improved results have not changed Mayor Nickels' beliefs.

"Each year we measure, maybe it's up a little bit, maybe it's down. But it's that long term tend that really counts," he said.

The mayor says that trend will eventually leave only half the snow pack up on the mountains, and consequently only half of the water the city of Seattle needs, by the year 2070.

The mayor says conservation may be the answer.

He says the city uses less water than it did in the mid 1960s today, but has 300,000 more customers.