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Global Warming Could Bring Us Wetter Winters by Tom Paulson Seattle Post-Intelligencer - November 9, 1999

For those who think global warming means the Pacific Northwest will someday inherit California's balmy beach weather, scientists at the University of Washington suggest you think again.

"The models say precipitation should increase," said Philip Mote, a UW professor of atmospheric science and head of a consortium of researchers looking at the regional effect of global climate change.

Today, Mote and other members of a federally sponsored research collaboration known as the Climate Impacts Group will describe what Northwesterners should expect within the next 50 years because of the worldwide disruption of climate patterns that most scientists today agree is already taking place.

Expect to see changes in salmon runs, forests, water resource and coastline, they say. Details about the climate group's findings and recommendations for mitigating the effects of these changes will be released at a news conference today.

In previous presentations, including testimony last spring to a state Senate committee, Mote and his UW colleagues predicted that:

• The snowpack will shrink because of warmer, wetter winters that will reduce water supplies in the region. Flooding, which caused $3 billion in damage to the Northwest in 1996-97, could increase in frequency.
• Forests are expected to shrink in size by virtue of the increase in average global temperature and diminished resistance to pests and fires.
• Agriculture could benefit from longer growing seasons, if not from the expected water shortages.
• National estimates of a rise in worldwide sea level would flood wetlands and significantly alter the Northwest coastline.
• Salmon runs appear to be governed, in part, by a newly identified weather phenomenon known as the Pacific Decadal Oscillation. The "PDO" is a localized weather pattern that comes and goes like El Nino and La Nina, but on a much smaller scale, and oscillates over decades rather than years.

Nathan Mantua, a UW researcher and part of the Climate Impacts Group, has helped identify the characteristics of the PDO, including major fluctuations in the salmon run. The Northwest has for the past few decades been in a warm and dry phase PDO, Mantua said, which may explain some of the decline in salmon.

Historical fisheries data that Mantua and others used to compare with decades of documented weather cycles have shown that salmon runs tend to migrate north to Alaska during a warm/dry PDO and return to the Northwest after the region enters a new wet/cool PDO.

Whether last year's record rainfall means the region is now re-entering a wet and cool phase PDO is still debatable, according to Mantua, but the evidence is building.

The Northwest Climate Impacts Group is part of a national project to assess regional effects of global climate change. In this region, the group at the UW includes researchers from the state Departments of Ecology and Health, the U.S. Department of Energy's Pacific Northwest National Laboratory in Richland and other regional institutions.

The effort is sponsored in part by the U.S. National Oceanic and Atmospheric Administration. The Northwest climate group led by the UW's Mote is the first of the regional groups to issue an impacts report.

Mote said few scientists question anymore whether global climate change is taking place and most accept the evidence that at least some of that change is "unnatural" and is a result of human industrial activities. The debate now should focus on how to identify the coming changes, he said, and how to prepare for them.

(This study also covered by The Oregonian, The Tacoma News Tribune, The Seattle Times, The Tri-City Herald, The Olympian, and The Spokesman-Review)