Local authorities in Juneau, Alaska have begun issuing evacuation orders. Now they’re worried about a future deluge from the retreating Mendenhall Glacier. The crown jewel of this precious system, Mendenhall Glacier, is conveniently located only about 12 miles outside of the capital city. Its rapid melting is igniting Haven-melting discussions about climate change and threatening communities across its border.
Today, Mendenhall Glacier has become a major tourist attraction, luring half a million visitors each year eager to see the glacier’s magnificent ice-towers. Yet the glacier’s picturesque façade hides a dark truth. Because of the warming climate, it is now retreating at an alarming rate of 100 to 150 feet each year. Unfortunately, this retreat has carved a depression into the ground that collects rain and snowmelt each spring and summer. Thus, the flood risk is made even worse.
As a remnant of the Little Ice Age, which ended in the mid-18th century, Mendenhall Glacier has been in decline since the late 1980s. Recent research shows that glaciers in southeastern Alaska—including Mendenhall—are some of the fastest-melting glaciers in the world. All this accelerated melting has led the glacier to create an ice dam. This dam produces a lake of meltwater that fills almost all of Suicide Basin. When the dam eventually fails, it does so spectacularly with potentially catastrophic glacial lake outburst floods (GLOFs).
Flooding caused by Mendenhall Glacier’s run-off has been a major worry for almost a decade and a half. In August 2023, an outburst released a record-breaking amount of water into Mendenhall Lake. This wave quickly raced down the Mendenhall River into Juneau. Not only has this flooding occurred, damaging, washing away and even demolishing homes while covering hundreds more with water.
The flooding event is driven by climate change amid glacial retreat,” stated Rick Thoman, emphasizing the link between climate issues and local flooding events. He stressed that climate change, specifically, is what’s driving this. Without it, he thinks we wouldn’t have any reason to be observing these changes occurring on the Mendenhall Glacier and in the lake and downriver.
Nicole Ferrin, a local weather guru, painted a dire picture of the threat. She says the next flood will definitely break all previous records. “This will be a new record based on all of the information we have,” she stated.
As Juneau prepares for potential evacuation, city officials are encouraging residents to get ready for emergencies. In response, the city has created emergency evacuation plans tailored to those most vulnerable residents who might have to evacuate with little notice. Information has been disseminated through community meetings and social media platforms to ensure that residents are aware of evacuation routes and safety protocols.
The story is still developing as meteorologists watch severe weather patterns that are developing and threatening the glacier’s stability. Rainfall, combined with more snowmelt, has the potential to raise water levels in Mendenhall Lake even higher, increasing flood risk.