Broadcast by KQED’s California Report, photo courtesy of UC Davis Environmental Research Center
HOST INTRO:
Skiers cruising down Tahoe’s white slopes this winter had a unique chance to learn about the surrounding ecosystem. UC Davis scientists clicked on their skis and led public tours down the mountain. KQED reporter Anna Guth joined one of these excursions and brings us this.
GUTH: In the cozy Alpine lodge at Palisades Tahoe, Alison Toy huddles over a microscope with an intrigued youngster.
TOY: Try closing one eye and only looking in the microscope with one eye... Tell me if you can see something.
GUTH: That “something” is native zooplankton, an algae-eating critter keeping Lake Tahoe clear and blue.
Toy…an educator for the UC Davis Tahoe Environmental Research Center… organized half a dozen winter tours for the public to “ski with a scientist.”
At her info table in the bustling lodge, Toy recruits participants for the afternoon’s adventure.
TOY: But you do have to be at an intermediate skiing level…You look like you're a solid skier, so, haha…
GUTH: The elementary schooler barely reaches the tabletop … but her dad confirms she’s an expert. And so they set off for the chairlift.
One of the tour leaders is volunteer docent Jo Anne Cobb. She bravely agrees to hold my poles, so I could use the microphone.
COBB: I don't want to drop your poles... Let me see, I can hold both…
Steady snow flurries batter our faces on this gloomy March afternoon.
COBB: We're on the chair lift. Today is actually a day when we're having some wind, some snow. So visibility is limited.
Not exactly Tahoe’s finest spring skiing conditions … We hop off the lift and carve halfway down a run through thick falling snow. The crew circles around UC Davis PhD student Kenny Larrieu for the first of the day’s two science talks.
He starts with the Caldor Fire, which devastated the area in 2021.
LARRIEU: It was extremely smoky here. There were times where you couldn't see more than 20 feet in front of you…
The wildfire spewed smoke and ash not only into the air but also the lake, creating what looked like falling snow underwater. To show this, he pulled out a laminated image…
LARRIEU: I have a picture of what it looks like at the bottom of Lake Tahoe, where you can see a bunch of these particles that just look like tiny specks in the water. And that's what we call lake snow.
To Larrieu’s surprise, the tiny particles disappeared quickly. Using a robot THAT DIVES UNDERWATER he discovered phytoplankton helped drag the particles to the lake’s bottom – and clear up the water.
LARRIEU: Understanding this interesting physical and ecosystem process will also help us to better understand and predict changes in Tahoe’s clarity going forward
After the talk, everyone’s focus turns back to the mountain storm – which is now howling. The group decides to finish inside over hot chocolate. Once in the lodge, we gather around Larrieu’s engineering professor, Alex Forrest, for the final presentation.
FORREST: The other portion of my talk, if we had been out skiing right now, would have been about snow and climate change.
Part of his research takes place in Tahoe, where he monitors increasingly unpredictable winters and snowpack for its effect on the lake.
He also takes his underwater robots to the polar regions, where he’s tracking how fast ice sheets are melting.
FORREST: Climate change is real… And we need to be able to model and understand what's coming toward us to protect our water, to protect our food, to protect our communities.
Cheryl Bri from Marin County listened intently until Forrest wraps up.
BRI: It… made it more worthwhile to be out here, rather than just enjoying ourselves… to see the important work that these guys are doing.
As some of us prepare to go home, the go-getter scientists suit up for the day’s last run, despite the slush and the ice.
The research center said every tour this year was at max capacity. They hope to offer the program again next winter.
For the California Report, I’m Anna Guth, at Palisades Tahoe.