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Forest Journalism for a Sustainable Future

Researcher: When Alaskan brown bears change food sources, forests change too

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A brown bear snags a sockeye salmon in Alaska. In warm years, red elderberries ripen early and Kodiak bears leave streams full of salmon to eat them. Photo: Jonathan Armstrong, CC BY-ND

After several years of studying brown bear ecology on Alaska’s Kodiak Island, I grew used to walking up streams into scenes of carnage. Where bears had killed and eaten spawning sockeye salmon, streambeds were littered with fish heads, jaws and whole carcasses, and plants on the stream banks were flattened. But at the peak of the stream spawning run in 2014, I was puzzled to find no bears or salmon parts. Salmon were dying naturally after spawning and piling up in streams, intact.

I’ve spent the last three years trying to solve this ecological puzzle. After extensive field and lab work along with researchers from Kodiak National Wildlife Refuge, Flathead Lake Biological Station and Oregon State University, we arrived at a fascinating conclusion.

In warm years, another favorite bear food – red elderberries – ripened early enough to overlap with the salmon season. This forced bears to choose between the foods. Surprisingly, almost all bears opted for berries over salmon. This choice has likely altered food webs, and will become increasingly common with expected climate warming. [Read more…]

Urban forests a key to survivability during climate-induced heat waves

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Graphic courtesy of NOAA Climate.gov

In May of this year, a hot spell broiled Boston. In June, extreme temperatures grounded Phoenix’s planes. Last week, Seattle suffered under record temperatures.

When a heat wave is forecast, the standard advice is to drink plenty of water, take frequent breaks and wear sunscreen. But for extreme heat events, those steps may not be enough.

Over 30 percent of all weather-related deaths in the United States are attributable to high outdoor temperatures, heat stroke or sunstroke. And heat waves are expected to increase in intensity with climate change.

How should U.S. cities prepare for extreme heat events? My research shows that the answer isn’t clear-cut, and that they should pursue multiple solutions rather than looking for one “best” option. [Read more…]

Bark beetles explode across warming continents; some forests may not recover

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Bark beetles have decimated 85,000 square miles of forest in the western U.S. since 2000, including this stand in California photographed in 2016. Photo: U.S. Forest Service

Editor’s note: The Earth’s warming temperatures are feeding an explosion of pine and spruce beetles across forests in North America, Europe and Siberia.

A host of scientific studies has documented the outbreaks.

And now scientists are warning that some of the affected forest ecosystems may never recover.

Writing for Yale E360, science reporter Cheryl Katz provided a comprehensive review of the science – and the devastation being wrought by the beetles, whose populations thrive in the new, warmer climes. [Read more…]

Climate change in the West: Preparing for a future that is here

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The Rice Ridge fire near Seeley Lake, Montana, produced in-town particulate-pollution readings higher than any ever recorded in Missoula County. Photo: U.S. Forest Service.

The vacation cabins that ring Seeley Lake emptied long before Labor Day this year. The tourists who come to swim, fish, and boat on the lake where Norman Maclean spent his summers had taken their fun and their recreation dollars elsewhere. Even many of the town’s full-time residents cleared out — as the Missoula City-County Health Department urgently recommended.

It happened because Seeley Lake, where the growing tourist trade has superseded Pyramid Mountain Lumber Co. as the primary driver of the economy, had turned into a hellscape. Smoke from the nearby Rice Ridge fire rolled down the surrounding hillsides with each night’s cooling air and filled the valley with so many pollutants that the county’s air-quality monitor was often pushed beyond its limits. Visibility shrank to less than a quarter mile, and streetlights along the main drag came on during cloudless days. [Read more…]

Wildfires, the smoking gun of Western climate change?

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The Rice Ridge fire near Seeley Lake, Montana, burned more than 160,000 acres this summer, forcing weeks of evacuation alerts and the worst air quality ever recorded in the mountain town. Photo: inciweb

As cooler temperatures and precipitation finally bring a hint of relief to smoke-weary Montanans, the unusual nature of summer 2017 is coming into focus and the influence of climate change is impossible to ignore.

Extreme weather has no doubt been the dominant story throughout the country this summer as hurricanes and tropical storms have ravaged the southeastern United States and wildfires have wreaked havoc in the West. A simple Google search will yield hundreds of stories about the impacts of these events, but very few mention climate change as a contributing factor. And that’s unfortunate.

Collectively, we have over 65 years of experience studying western climate and forest systems, and we are among the authors of the forthcoming Montana Climate Assessment (MCA), a report that focuses on climate trends and their consequences for three of Montana’s vital sectors: water, forests, and agriculture. The Assessment sheds some light on common questions about climate change and its effects on things like drought and wildfires. [Read more…]