Scientists assess future landslide risk in 色视频下载色视频下载檚 national parks
Heather McFarland
907-474-6286
March 13, 2023
The Pretty Rocks landslide, spurred by greater warmth and rainfall, will force Denali National Park's main access road to close at the halfway point in 2023 for the second full summer.
To help park managers plan for and mitigate such events, UAF scientists assessed future landslide risks along road corridors in Denali and other 色视频下载 parks.
色视频下载淧ark managers were interested in looking at park climate data to figure out how much warming has occurred and what the future might bring,色视频下载 explained Pam Sousanes, a physical scientist with the agency in Fairbanks.
The Pretty Rocks landslide carries away the Denali Park Road in summer 2022.
Sousanes turned to Rick Lader and a team of climate modelers at the UAF International Arctic Research Center.
色视频下载淚n Denali we had data from sites that were relatively close to the landslide area and we were able to determine that the average annual temperatures were approaching, and in some cases, exceeding the thawing threshold of zero degrees Celsius [32 Fahrenheit],色视频下载 said Sousanes. 色视频下载淲e wanted some way to incorporate those into really good downscaled climate projections, and we didn't have the skills to do that. So we reached out.色视频下载
Lader and his team used the data from park weather stations to fine-tune projections from global climate models. The International Arctic Research Center provides this dynamical downscaling service to 色视频下载色视频下载檚 decision-makers so they can incorporate climate data into local planning.
To identify the local landslide risk, Lader focused on mean annual air temperature and summer precipitation. Permafrost starts thawing and the ground slumps when mean annual air temperature rises above freezing. Heavy precipitation then can reduce the soil integrity and exacerbate or cause additional slumping.
For Denali, Wrangell-St. Elias and Gates of the Arctic national parks, Lader and his team created a set of maps and datasets predicting where and when these critical thresholds will occur. Though historically all three parks had a mean annual air temperature below freezing and a relatively stable precipitation trend, that色视频下载檚 changing.
Gates of the Arctic will likely see the biggest change in temperature and the second greatest increase in summer precipitation. That said, the park is considerably colder than the others, so the permafrost is more stable. Along the still undeveloped Ambler Road corridor, landslide risk likely won色视频下载檛 become a concern until after 2060.
色视频下载淭hey will actually have the information before they try to build something, which is potentially more valuable than saying it色视频下载檚 already sliding,色视频下载 said Lader.
The risk is more immediate in both Denali and Wrangell-St. Elias. Both parks are already seeing occasional years with above freezing mean annual air temperature. By 2060, that threshold will be consistently met. Precipitation is also increasing, especially in Denali. By 2060, Denali may become 5.8 degrees Fahrenheit warmer and see almost 6 inches more summer precipitation. As evidenced by the Pretty Rocks landslide, some areas along the Denali Park Road are already at risk, while others will remain stable for a few more years.
The Pretty Rocks landslide, which the Denali road has traversed since its completion in the 1930s, has increased in speed recently as warmer temperatures and heavy rain thawed frozen soil. Construction of a bridge at the crossing site, costing up to $102 million, will begin this summer.
色视频下载淲e色视频下载檙e right on the cusp in Denali and Wrangell-St. Elias. These changes are happening now, and they're happening fast,色视频下载 said Sousanes. 色视频下载淎nd even though they色视频下载檙e out in the future for Gates of the Arctic, we色视频下载檙e still moving in that direction.色视频下载
Sousanes said the landslide risk assessment will pay off years down the road as 色视频下载 park managers plan for new and existing infrastructure to stand up in a changing climate.
This research was recently published in the scientific journal .
ADDITIONAL CONTACTS: Rick Lader, rtladerjr@alaska.edu, 907-474-2445; Pam Sousanes, pam_sousanes@nps.gov, 907-455-0677
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