An image of the Oso debris field four weeks after the fatal mudslide in 2014.
An image of the Oso debris field four weeks after the fatal mudslide in 2014. Brendan Kiley

Climate science has come a long way from where it was even a decade ago. While scientists have long described how man-made greenhouse gas emissions are linked to global warming, it's only in recent years that they've been able to hone in on something the average person can more easily get his or her head around: local climate change impacts.

Today, scientists at the University of Washington released the most comprehensive look at Puget Sound climate projections yet. The report describes local warming that could double over the next century, sea levels that could rise between four and 56 inches, ocean acidification, and increased risk of flooding. The report also delves into human health impacts, which include risks related to poor air quality, allergens, wildfire, changing disease patterns, extreme heat events, and threatened water supplies.

Since the last time local scientists put out a similar report in 2005, the latest report has also added a major new section: landslides.

The landslide section mostly lays out the groundwork for future research questions. But because of warmer temperatures that thaw and destabilize soil, as well as more heavy rain events, scientists anticipate increased risk of landslides in winter and early spring.

On top of landslide risk, scientists have been able to map out detailed flooding projections. The report shows that heavy rain events, sea level rise, and receding snowpack will all likely contribute to increased risk of local floods.

But the other interesting takeaway from the report is just how devastating certain changes can be to human health. New research has shown that increased frequency of heatwaves could result in a disproportionate mortality rates and hospitalizations for vulnerable people in King County.

"We've learned that looking across the state there's more sensitivity here because we're not adapted to it," report coauthor and University of Washington Climate Impacts Group scientist Guillaume Mauger said. "People just haven't developed the habits and culture around dealing with those hot days."

The primary aim of putting out this kind of report, of course, is to help communities use the information to adapt. Because the science has shown that rising sea levels could flood more than 1,100 acres on the Swinomish Reservation, the Swinomish Indian Tribal Community is now putting adaptation measures into practice by devising a coastal protection plan. Flooding projections also changed the design of the new Anacortes water treatment plant, which now avoids putting any electrical equipment below a 100-year flood elevation. And because of the landslide risks mentioned above, King County is now considering climate projections in its road maintenance programs.

The accomplishment of the new report, in Mauger's mind, is how much the science has revealed about local impacts. "What's significant to me is we're doing climate impacts research, and we've been doing enough of it so we can have a really place-based, comprehensive picture, the fruits of 20 years of research," he said.