Wednesday, June 9, 2004

Major water shortages predicted

Legislators ‘warm’ to idea of climate change

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By GREG STAHL
Express Staff Writer

Idahoans must brace for warmer temperatures, less snow and longer summer seasons. In fact, it’s something they’ve already been gradually doing as the earth has been warming and the climate has been changing throughout the last century.

The West, without question, is moving into a transitional period when precipitation will dwindle and snow will melt earlier, said Phillip Mote, a researcher with Climate Impacts Group from the University of Washington. What that means is management of water in Idaho and throughout the West has to change.

What’s more, Mote said the trend toward warmer, drier weather is not a slap from Mother Nature. The majority of scientists working on the issue agree that the warming trend is human-caused, he said.

During the next 50 years, global temperatures could rise 7 degrees, Mote said.

"An increasing body of observations gives a collective picture of a warming world and other changes in the climate system," Mote said. "There is new and stronger evidence that most of the warming observed in the last 50 years is attributable to human activities."

Mote spoke Thursday, June 3, to the Idaho Legislature’s Expanded Natural Resources Interim Committee at a daylong meeting held at Boise City Hall. The House and Senate committee is charged with looking for solutions to Idaho’s complex water conundrums.

Above all, Mote stressed three take-home messages.

First, humans are changing the global climate, and the changes will become increasingly evident.

Second, warming will decrease snowpacks and exacerbate summer water shortages. "Some of these changes are already becoming apparent in Idaho," Mote said.

Third, further global warming will create a climate-driven depletion of the Snake River Plain Aquifer.

"This may well be what we’re in, some combination of a 100-year drought and global warming," Mote said. "We know it means warmer, but we don’t know what else."

Mote said carbon dioxide in the earth’s atmosphere is up 32 percent in the last 150 years and is now higher than at any time in the last 23 million years. Methane, too, has increased dramatically, particularly since the turn of the 20th century. Since 1750, methane has increased more than 150 percent.

A graph of the global average temperature coincides almost perfectly with graphs of methane and carbon dioxide production. Around the Industrial Revolution in the 1880s, all three graphs spike skyward.

"This is a huge issue that is going to have to be dealt with eventually," Mote said. "Some of these changes are already occurring. These projections of future climate that show that there is less snow and less water in the summer is what’s already been happening."

To help illustrate the point, Mote showed a slide depicting the South Cascade Glacier in 1928 and again in 2000. In the more recent photo, the glacier is clearly half the size it was 72 years earlier. And that’s only the beginning of the melt, he said.

"Throughout the west, spring snow runoff has been coming earlier in recent years, typically 10 to 40 days with the biggest changes in areas at lower elevations. Most of the West has seen increases in March flows, just as predicted in the models. June flows have been dropping, and in Idaho, that’s in the 10 to 30 percent range.

"It isn’t 10 to 40 years in the future that we’ll notice it. We’re already noticing it. It is pretty well agreed that there is warming, and there will be continued warming."

Sen. Clint Stennett, D-Ketchum, said he believes the presentation was a quantum leap for members of the Idaho Legislature.

"For many of these people to take the time to sit through a serious presentation on climate change—some of them don’t believe in it. They think it’s bad science," Stennett said.

Stennett said the committee’s effort was "a good beginning."

"I’ve never really bought on big to the whole global warming theory," said Sen. Dean Cameron, R- Rupert. "But I was impressed by the way he laid out the evidence."

Rep. Tim Ridinger, R-Shoshone, said the presentation was informative, but daunting.

"After we digest it, we’re probably going to have to have some of these people come back," he said. But the gist of the problem is clear, he said.

"Somehow, we’re going to have to come up with some additional storage to have the water in years when we need it," he said. "We don’t have to reinvent the wheel. We just have to re-shape it to fit Idaho."

But Mote noted that other predictions include a reduction in the amount of snow in lower elevations, which could make it harder to store water in reservoirs and reduce the natural recharge of the expansive Snake River Plain Aquifer that provides water for much of southern Idaho.

Ron Abramovich, a water supply specialist with the federal Natural Resources Conservation Service, said that even if the same amount of precipitation fell as rain instead of snow, it would move through the watersheds early in the year and before the reservoirs are ready to begin capturing water.

"You’d have to more closely watch the management of reservoirs," said Abramovich, who made the comment in a separate interview with The Associated Press.

Mote said allowing more flexibility in spring river management could aid Idaho and other Northwest states in addressing the changing snowfall and rain patterns.

"We’d have less concern for flood control and more concern on keeping reservoirs full in the summer," he said.

Mote also said the average temperature increase would affect salmon, which rely on snowpack to provide water for their journey to the Ocean.

In some streams, flooding will increase, scouring eggs from their streambeds at a critical time, Mote said. In other places, warmer water temperatures and lower stream levels will hurt fish in the summer.

"There will be some stocks of salmon that will have a difficult time with global warming," Mote said.

(The Associated Press contributed to this story.)

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