By Randy Trick, Peninsula Daily News
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Dungeness Spit could become a sliver of marshland, or disappear completely.
Ediz Hook would still exist, but be battered by storms until it was unusable.
The spits protecting the opening to Sequim Bay would disappear, making the bay vulnerable to waves and storms.
Around Port Townsend, most freshwater marshes would fill with salt water and between 80 and 85 percent of what few beaches exist on both sides of Admiralty Inlet would be lost, the report said.
The study, which focused on 11 coastal habitats in Washington and Oregon, included the populated areas of the North Olympic Peninsula.
The report examined the impact of rising sea levels on the diverse geography of the Pacific Northwest.
If ocean levels increase 0.69 meters, or 27.3 inches, by 2100, water will erode Puget Sound beaches, inundate tidal flatlands and harm salmon habitat throughout the Pacific Northwest, the report said.
The report did not examine whether climate change is occurring or likely, but focused on probable consequences if warnings are correct.
"Projections of future climate will always be accompanied by some degree of uncertainty, but this should not be used as an excuse for inaction," the report said.
Global warming contributes to rising ocean levels through thermal expansion of the water, as well as the melting of glaciers and polar ice fields, the report said.
Global warming is said to be caused by emissions.
If sea levels rise faster than expected, Dungeness Spit is expected to disappear altogether, the report said.
The report also emphasizes the importance of preserving what coastline there is in the Pacific Northwest that is untouched by development.
Overall, if the world's oceans rise as much as the U.S.-sponsored Intergovernmental Panel on Climate Change has predicted, about 65 percent of beaches around the Pacific Northwest would be lost to erosion, the Wildlife Federation estimated.
Along the North Olympic Peninsula, tidal flats are expected to be inundated and ocean bluffs are expected to be beaten and eroded.
Because most of the land along the North Olympic Peninsula is elevated and rivers lose elevation quickly toward the ocean, the area is not expected to see a lot of usable land lost.
But if tidelands disappear, and freshwater marshes fill with salt water, the consequences for fish and wildlife would be serious.
"Some species may be able to respond to changes by finding alternative habitats or food sources, but others will not," the report said, adding that the impact depends on how fast the water rises.
Changes in tidal wetlands could diminish salmon habitat, while migratory birds looking for food on tidal flats or coastal marshes might not find enough.
The impacts would also affect other species that depend on coastal animals for their food.
Other impacts of global warming, such as increased rainfall, higher water temperatures and lower average snowpack, would also affect wildlife habitat.
Algae blooms could increase, oxygen levels could drop and inland water salinity could rise, the report said.
The National Wildlife Federation's report can be found at http://www.nwf.org/sealevelrise.
Reporter Randy Trick can be reached at 360-417-3537 or at firstname.lastname@example.org.
The Associated Press contributed to this story.