Despite the fact that Denali National Park covers more than 3354 square miles (8657 sq. km), there is only one road to be found there. The lone route carries visitors-mostly on shuttle buses-into the spectacular interior of the park, offering them glimpses of the vast wilderness and abundant wildlife that is found there. If the skies are clear, they may even get to see the park's namesake mountain, which happens to be the highest in North America.
Throughout the busy summer travel season, the Denali Park Road-as the route is officially known-sees a steady stream of traffic. But last week, the National Park Service was forced to close this lonesome highway due to unprecedented landslides that has seemingly been brought on by the effects of climate change.
Rapidly Melting Permafrost
It's no secret that 2021 has been an extremely warm year across the entire planet. In fact, record setting heat in North America and Europe led the National Oceanic and Atmospheric Administration to declare July the hottest month ever recorded. Unsurprisingly, this has had a dramatic impact on the Arctic in particular, with unprecedented heatwaves in Siberia, Greenland, Canada, and Alaska.
The warm temperatures throughout the summer of 2021 have left their mark on Denali National Park too. One of the park's defining characteristics has always been its permafrost landscape, which is defined as soil or rock that remains below 32ºF (0ºC) for at least two consecutive years. And while the surface located just above the permafrost may thaw and freeze with the seasons, the ground beneath has remained mostly frozen for centuries at a time.
In recent years, thanks to consistently warmer conditions s in general, that permafrost hasn't always been quite so "perma" however. In recent years, its temperature has hovered within a degree or two of freezing. This summer, the heat waves have pushed the permafrost above that mark, causing it to melt rapidly-something that could have a lasting impact on the local flora and fauna, while impacting the park's hydrology in profound ways.
Landslides Close Road
So what does all of this have to do with the one and only road through the national park? Part of that road crosses over a section of unstable ground known as Pretty Rock Landslide, which is found on the way to a place called Polychrome Overlook. For years, this section of the road has been somewhat unstable, forcing the Park Service to make repairs on a regular basis. This year however, the instability has become much more problematic than ever before.
In a press release announcing the closure of the park road, Denali's superintendent Don Striker says, "Changing climate is driving frozen ground to thaw, resulting in unpredictable and increasing landslide movement rates at Pretty Rocks that are unprecedented in the history of the park road." He goes on to add, "We cannot safely keep up with the accelerating rate of landslide movement caused by permafrost thaw currently occurring in association with the Pretty Rocks Landslide."
Apparently, as the permafrost has thawed, the ongoing permanent landslide found along the road has caused the ground to shift. It has gotten so bad that at one point, the road actually sunk 10 inches (25.4 cm) in a single day. That is a scary prospect for a route that is frequently used to shuttle tourists through the park.
Permanent Closure?
Currently, the road is closed past Pretty Rock for all but essential personnel. Most of the Denali staff is in shutdown mode, closing up facilities for the season. Considering the extensive amount of work that needs to be done to both repair and bolster the road, it seems unlikely that it will be fixed prior to the arrival of the Alaskan winter. Which begs the question as to when it will be full opened again.
A few years back, a study was conducted to investigate what would need to be done in order to fix the route. At the time, Alaskan Senator Lisa Murkowski estimated that it would cost "tens of millions of dollars" to repair and reengineer for the shifting conditions. That's a lot of money for the Park Service to spend, even with a budget bolstered by the new Presidential administration.
With climate change causing the permafrost to continue to thaw, Denali National Park is likely to continue to face challenges moving forward. The question is whether or not the road will ever reopen for its full length? The shifting landscape due to warming conditions is likely to make other sections unstable as well, which could mean less access to this amazing wilderness.
This feels like yet another example of the warnings of the impact of climate change that we've had for so long. Only now, the impact is happening for real and it's going to change a lot of environments and ecosystems as we know them.
