Everybody's National Parks | ENP 19.8 Yosemite: Scratching The Surface: Geology & Rock Climbing In Yosemite National Park
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  • ENP 19.8 Yosemite: Scratching The Surface: Geology & Rock Climbing In Yosemite National Park
    Park Geologist Greg Stock. Photo Credit: National Park Service Park Geologist Greg Stock. Photo Credit: National Park Service

    Yosemite Park Geologist Greg Stock and Yosemite Mountaineering School Director Dave Bankston

    This episode, number eight in our Yosemite National Park series, is for the geology geeks and climbing enthusiasts. If neither of those monikers interests you right now, just wait: you’ll want to pick up a rock hammer or clip yourself to a rope by the end of the show — possibly both! To start, Bryan chats with Park Geologist and Ranger Greg Stock on the forces that shaped Yosemite’s stunning scenery and the toll our warming climate is having on the park. Then, Danielle dives into mountaineering with Dave Bengston, director of Yosemite Mountaineering School, to learn about the highs and lows of this perennially popular park activity.
    Park Geologist Greg Stock at the Lyell and Maclure Glaciers by Jean Redle Park Geologist Greg Stock at the Lyell and Maclure Glaciers - photo by Jean Redle

    Yosemite’s First Park Geologist Charged with Keeping Visitors and Infrastructure Safe from Rockfalls

    “You know, when I talk about geology, I start with a very simple phrase that I think captures the essence of geology and Yosemite, and that is glaciers on granite. That’s really the essence right there.” Greg’s reverence for Yosemite’s eons-old granite is palpable. As the park’s first-ever geologist, it’s his job to monitor the cliffs, rocks, and peaks that make up the famous landscape. His surveys and studies provide rangers with the scientific data they need to anticipate dangerous rockfalls, thus protecting park guests and structures from potentially fatal incidents before they happen. So, what causes rockfalls in the first place? Greg points to a variety of processes, all working in tandem to weaken the granite or peel it away like one would the layers of an onion. “Rockfalls can happen for a bunch of different reasons and we have rockfalls all year round,” he says. And, while there are areas of the park that experience minimal episodes, it’s important to note that Yosemite is a living, breathing place. “I think you can sleep safely [in the park] but we do remind people that rockfalls can happen at any time,” he says. “There is always the remote possibility of an infrequent large volume rockfall, right? You’re still in the wild despite all the infrastructure. It’s still the park. It’s still the wild.” A 2008 rockfall in the Curry village proves Greg’s point. His work, however, minimized the impact that event had on the Yosemite and its guests.
    Park Geologist Greg Stock at Glacier Point by Steven BumgardnerPark Geologist Greg Stock at Glacier Point - photo by Steven Bumgardner

    Impacts of Climate Change: Studying the Maclure Glacier as John Muir Once Did

    Urgency isn’t a word often applied to the study of 100 million-year-old granite formations but the growing climate crisis is changing the conversation. Beyond the growing instability of the rock, Greg has seen other clues that point to warming’s impact. In 2012, he followed in the footsteps of his hero John Muir, taking a survey of the Maclure Glacier in roughly the same manner as the famed naturalist: sinking stakes into the ice to take their measure. While he was thrilled to see the glacier still moving - at a rate of about an inch per day - he noted that it’s only 20% the size that Muir would’ve walked on. Add to this the eerie realization that many of the glaciers Muir himself took note of no longer exist and it’s easy to become fatalistic about the park’s future. Greg remains optimistic. “You know this is, after all, a human-caused problem and so it ought to be one that humans can solve.”
    Yosemite Mountaineering SchoolYosemite Mountaineering School
    Yosemite Mountaineering SchoolYosemite Mountaineering School

    Rock Climbing In Yosemite

    Solving problems is at the heart of rock climbing and Dave Bankston has spent decades teaching visitors the how and where of Yosemite mountaineering.”I’ve been a climber here in Yosemite since 1974...this is one of the best places on the planet.” And one of the most popular, attracting climbers from all over the world. There’s a universality to the activity that transcends language and makes it easy for mountaineers from every country to enjoy the seasons and the scenery. There’s also a curriculum for every skillset. From basic rope handling to advanced climbs, the Yosemite Mountaineering School covers all aspects of climbing preparedness. If climbing isn’t your thing, the school holds Nordic ski lessons in the winter so visitors can hit the slopes or stride cross-country through the breathtaking powdery landscape.

    Sans snow, Yosemite offers a myriad of climbing options with plenty of seasonal interest to go around. Spring can bring wet weather but optimal waterfall views while a warm summer offers mountaineers the chance to get up into the high country. Autumn attracts climbers with its promise of consistent temperatures and blazing color. And, yes, there are accessible climbs in the Yosemite Valley during the winter months. As for climbing with kids, Dave says the sport is accessible to all ages. “We’ve had very, very young kids do extremely well. You know, three, four years old. We’ve also had older kids that are just terrified.” Ultimately, the choice is theirs. The school is positioned to help everyone, regardless of skill, engage with the park in the most holistic way possible. “Ideally, we don’t leave a trace. I mean, our goal is to come here, enjoy the national park and the natural rocks and whatnot, and then go away and have not changed it in any way so the next person can have that same sense of adventure, that new feeling for the climbing site.”

    Ready to scale a cliff or unearth the secrets of Yosemite’s granite formations? Listen in for more insights from Dave and Greg and their favorite park memories.
    Yosemite Mountaineering School Director Dave Bengston climbing Turtleback Dome_Kenny KarstYosemite Mountaineering School Director Dave Bengston climbing Turtleback Dome. Photo by Kenny Karst

    Discussion Includes The Following:

    • 0:01 - Introduction to the episode’s guests: Geological Park Ranger Greg Stock and Dave Bengston, director of Yosemite Mountaineering School, plus Danielle reads a sweet note from a listener
    • 2:54 - Bryan exposes a geologist’s best-kept secret and gets to know Greg Stock
    • 4:08 - Fatal rockfalls and shifting attitudes toward climate challenges drive the National Park Service to hire a geologist for Yosemite National Park
    • 5:44 - A geological timeline: The formation of Yosemite’s iconic granite peaks El Capitán, Half Dome, Cathedral Peak, Lembert Dome, and Pothole Dome
    • 7:26 - The Merced River
    • 8:10 - A closer look at the processes of exfoliation, glacial erosion, and rockfalls
    • 9:41 - The dynamic, year-round forces that trigger rockfalls
    • 12:29 - Quantitative rockfall hazard risk and assessment and front-country campsite safety; an incident at Curry Village (2008)
    • 15:20 - Yosemite’s fading ice: The Lyell and Maclure glaciers
    • 16:38 - Replicating John Muir’s 1872 Maclure glacier survey
    • 18:22 - The alarming truth about the future of Yosemite’s glaciers
    • 19:51 - Greg tips his rock hammer to John Muir
    • 22:23 - Hiking, rappelling, and taking modern measurements in the backcountry
    • 24:39 - Dome upon cliff upon dome: Greg shares his favorite Yosemite memory
    • 26:24 - Danielle dives into mountaineering at Yosemite and gets to know Dave Bankston
    • 28:48 - From climbing to skiing: Four seasons of activity
    • 31:18 - Universal language: Yosemite’s international mountaineering appeal
    • 32:22 - Coming to terms with climbing lingo
    • 33:20 - Newbies and indoor climbers welcome!
    • 37:25 - Outdoor climbing vs sport climbing
    • 38:56 - The perfect climbing spots for every level: From Toulumne Meadows, Swan Slab, and Puppy Dome for beginners to pitch climbing on East Buttress for intermediate climbers and El Capitán for advanced climbers
    • 41:51 - All about pitch climbing
    • 44:26 - Mountaineering School: Screening process
    • 45:12 - Mountaineering School: Classes, climbs, and conditions
    • 47:41 - Mountaineering tips for families
    • 48:30 - Female climbers on the ascent
    • 49:05 - Plan ahead for peak season climbing
    • 49:51 - Free Solo Climbing
    • 51:57 - A trip up Mount Conness: Dave shares his favorite climbing memory

    CATEGORIES: PodcastsYosemite