Bretwood Higman ’99 and Noah Finnegan ’99 featured in New York Times piece on landslide-generated tsunamis
Higman studied geology and Finnegan studied geology and environmental and technology studies at Carleton.
Bretwood Higman ’99, geologist, and Noah Finnegan ’99, geomorphologist, were both featured in a New York Times piece titled, “A Landslide in Alaska Set Off a Tsunami. There May Be More to Come.”
Another voice in the story, seismologist Jackie Caplan-Auerbach, has also participated in workshops with Carleton’s Science Education Resource Center (SERC), speaking about teaching computation.
Nearly 500 feet up a near-vertical rock face, scraped clean of soil and alder trees, Bretwood Higman, a geologist, looked down across the Tracy Arm fjord in southeast Alaska at a scene of devastation.
At 5:26 a.m. on Aug. 10 last year, a mass of rock with a volume 24 times larger than that of the great pyramid of Giza crashed down the mountainside, sending a wave of water 1,578 feet up the opposite wall and setting off a tsunami that roared down the fjord. It swept over the ridge that Dr. Higman was now standing on. The whole thing took about a minute.
Dr. Higman was part of an international team investigating the aftermath of the geologic event, the second largest landslide-generated tsunami on record. Using computer models, the researchers were able to recreate the landslide and tsunami, as well as a standing wave called a seiche that sloshed back and forth for 36 hours after the landslide.
Among other things, the new study, published on Wednesday in the journal Science, revealed how tricky it is to predict such catastrophic landslides before they take place.
Jackie Caplan-Auerbach, a seismologist at Western Washington University and an author on the new study, was among the first to hear about the tsunami: Her neighbors, whose boat was anchored at sea some 50 miles from the landslide, texted her about a strange surge of water that had hit their vessel. Other firsthand accounts trickled in from Harbor Island, where camping kayakers said their gear had been carried away by the wave, and from a 150-passenger cruise ship, the National Geographic Venture, that was sitting just outside the fjord.
The stakes are high for detecting these events ahead of time. Although no vessels were in Tracy Arm fjord proper when the landslide hit, that mostly came down to luck: It was early morning and not many boats were about.
“The bar is, can we do better than missing most of these,” said Noah Finnegan, a geomorphologist at the University of California, Santa Cruz, who was not involved in the study. “So getting a handle on why these precursors happen and what their relationship is to catastrophic collapse is an area many people are interested in.”