There will be winners and losers in the Pacific Northwest as global temperatures rise over the next 50 years, as most of the world’s global-warming experts predict.
If average temperatures rise 2 degrees Fahrenheit by 2020 and 4.5 degrees by 2050 as forecast for this region, salmon, forests and hydropower-dependent industries may suffer.
But some farmers in Eastern Washington, Oregon and Idaho could benefit by having a longer growing season.
Rising seas would mean moving parts of U.S. Highway 101 along the Oregon coast, and warmer springs could result in less summer hydropower and more orchard pests in fruit-growing regions of Eastern Washington. The warmer temperatures also could bring more smog with a predicted increase in wintertime deaths from air pollution in urban centers, including Spokane and Seattle.
These are some of the intriguing, and still tentative, scenarios an estimated 120 scientists, industry representatives and public observers discussed Monday at a conference on climate change at the Bell Harbor International Conference Center.
The invitation-only workshop was sponsored by the National Oceanic and Atmospheric Administration and the National Aeronautics and Space Administration. It is one of nine regional sessions leading up to a national conference in Washington, D.C., this fall. It will provide information for an international summit in December in Kyoto, Japan, where industrial nations will propose specific targets to reduce the world’s buildup of greenhouse gases.
Emissions of carbon dioxide, methane and nitrous oxides - gases that trap heat in the atmosphere - are the major cause of global warming.
There is a growing scientific consensus that world climate is being altered by human activities, according to the 1995 Intergovernmental Panel on Climate Change, a United Nations-sponsored body comprising 2,500 of the world’s top climate scientists.
“The impacts we predict are more than plausible; they are probable,” said conference organizer Ed Miles, a marine studies professor at the University of Washington and a member of the 1995 climate panel.
The world has been warming up since the Industrial Revolution, with a 1 degree Fahrenheit rise in 100 years and a 4- to 10-inch rise in sea levels.
Total precipitation has increased 6 percent, and the frequency of heavy downpours of more than 2 inches per hour is on the rise.
That rate of change is accelerating, Miles said. The last 15 years have included 10 of the warmest years on record, and scientists are predicting more extreme weather in the next century, including droughts in some regions and torrential rains in others.
A much smaller group of scientists - many working for, or associated with, industry-funded coalitions and conservative think tanks - disagrees that changes will be that extreme.
Even among those who acknowledge the trend, there is a significant degree of uncertainty about the impacts of global warming over the next century, the scientists said.
“While the various computer models that are used to predict future climate tend to agree on the global aspects of how climate will change, they are not yet sophisticated enough to produce dependable, consistent projections of climate change for small regions such as the Pacific Northwest,” says a June 1997 paper from UW’s Climate Impact Group.
But regional information is essential for government policy-makers, said John Gibbons, director of the White House’s Office of Science and Technology Policy.
Gibbons, a physicist, will help the Clinton administration propose goals to reduce greenhouse gas emissions; those goals are to be presented at Kyoto. He’d like to see U.S. emissions cut back to 1990 levels, an admittedly difficult goal that faces opposition in Congress.
If the White House and Congress fail to act, the world will face accelerating climate change that could triple the greenhouse gases in the atmosphere in the next century, Gibbons said. “That is a recipe for disaster,” he said.
Scientists studying climate trends in Washington, Oregon and Idaho shared their thoughts on what is likely to happen in the 21st century. Among their predictions:
By 2050, the region will have wetter winters and hotter summers. Because less winter precipitation will fall as snow, there will be less snowpack accumulating at higher elevations and, therefore, less water storage.
Snowmelt will occur earlier in the year due to warmer temperatures. Rivers will swell with runoff in the winter with summertime flows decreasing.
The Columbia River, fed by many sources including mountain snowpacks, will have lower flows from August through January. That could hurt energy production and fish survival, yet also would decrease the water supplies available to irrigate 7 million acres of farmland in the Columbia River basin.
Freshwater fisheries, especially small rivers and lakes, are expected to be most vulnerable to climate change.
Hotter summers could increase forest fires and leave more forests subject to pests, according to Jerry Franklin, UW professor of forest resources management.
In Eastern Washington, there will be “significant replacement of forests with shrubs and steppes” as forests retreat north and to higher elevations, he said. However, it is not known how fast this will happen or how adaptive the forests will be, Franklin said.
On the coast, climate change will show up in rising seas: about 3 inches by 2020, 10 inches by 2050 and 20 inches by 2100. Because much of Puget Sound is being thrust upward by geological movement, many areas will stay intact. But one-third of the Puget Sound shoreline already is considered unstable, said Marc Hershman, director of UW’s School of Marine Affairs.
Vulnerable areas include the south Puget Sound region, including Olympia and Tacoma, and the outer coast of Washington and Oregon.
While scientists debated the uncertainty of these predictions, other observers asked whether the public is ready to worry about problems a half-century away.
“This workshop is moving in the right direction,” said Jim Good, an oceanography professor at Oregon State University. “We need to regionalize and localize this information so people will pay more attention to it.”
, DataTimes ILLUSTRATION: Graphic: The Earth will be a hotter place to live