“This is the most precious piece of paper in my possession that cannot be replaced.” Jerry Brock flips to a page in the back of Colorado’s High Thirteeners: A Climbing and Hiking Guide by Mike Garratt and Bob Martin. He traces an index finger down a list of the tallest mountains in Colorado. To the right of the first 116 names, dates are penciled in tiny numbers: month-day-year.
“I wrote the day I climbed each peak in the book,” he explains. “The recording was most often made on summit day.”
Brock started exploring Colorado’s Rocky Mountains when he began work at Los Alamos National Laboratory in March of 1995. During the week, he worked on computational fluid dynamics in the Lab’s Theoretical division, and on many weekends he’d head north with a group of local mountaineers. “Early on, I took advantage of climbing opportunities with people who had more experience,” Brock remembers. “In August 1995, I climbed my first fourteener [mountain at least 14,000 feet above sea level] because my roommate was going.”
Before long though, Brock was often summiting peaks solo, sometimes embarking on multiday backpacking trips to reach the top of a mountain—or several mountains. “I bought a 1998 4x4 Toyota Tacoma with a 6‑foot bed,” he says. “I’d often leave work on Fridays around noon, drive to Colorado, sleep in the bed of the truck, and get up very early to climb.”
Brock still has that Tacoma, in which he slept in October 2020, the night before he summited Mount Elbert, Colorado’s highest peak—14,433 feet above sea level. That climb was also the last in his quest to summit every peak above 13,800 feet in Colorado. “My wife carried a bottle of champagne to the top for us to celebrate,” says Brock, noting that his wife and daughter accompanied him on a handful of hikes. “I could not have accomplished this goal without their support.”
Brock says he had summited around 75 peaks when he realized that all 116 above 13,800 feet might be attainable. But he never put himself on any sort of schedule. He says the few times he had to bail on a summit attempt due to poor conditions and then try again were “just part of the process.” Mount Elbert, however, was the exception. “I knew I was moving to Washington, D.C. for an assignment on the Defense Programs Science Council,” Brock remembers. “I knew I had to do Elbert—and a few others—before I left New Mexico.”
Brock ended up spending three years in the nation’s capital; one as a senior technical advisor on the Defense Programs Science Council (part of the National Nuclear Security Administration) and two as a senior technical advisor supporting the Joint Staff Strategic Stability Directorate in the Department of Defense.
In July 2023, Brock returned to Los Alamos, where he now leads the Office of Stockpile Assessment and Strategy. In this role, Brock is responsible for orchestrating the annual assessment reporting process—one of the Lab’s most important deliverables—that is mandated by Title 50 U.S. Code Section 2525. Every year, the process culminates in a letter from the Laboratory director to the secretary of energy, the secretary of defense, and the chair of the Nuclear Weapons Council that describes the Lab’s confidence in the safety, reliability, and performance of four nuclear weapons systems: the B61 family of bombs, the W76 family of warheads, and the W78 and W88 warheads. Los Alamos is responsible for maintaining these weapons systems without nuclear testing. Instead, the Laboratory relies on nonnuclear and subcritical experiments coupled with advanced computer modeling and simulations to assess the status of these weapons. This science-based approach is called stockpile stewardship.
“I work with staff and leaders from across the Laboratory to help communicate their assessments,” Brock says. “This important work underpins Los Alamos’ and the nation’s confidence in the nuclear stockpile.”
Looking back over his 29-year career at Los Alamos, Brock says that “I've tried to fully commit to whatever job I’m doing.” He explains that for 25 of those years, climbing mountains was a “release” that took him away from his desk and into the wilderness. These days, Brock’s hiking is much more casual, and he recalls his quarter-century of Colorado summits with a mix of enthusiasm and nostalgia. “It was so mentally and physically tough—it required me to completely pivot away from work,” he says. “And I just really enjoyed the challenge and reward of climbing each peak.” ★