Residents in Juneau, Alaska, are facing evacuation as the rapidly melting Mendenhall Glacier releases water from its dam, creating a significant risk of flooding in the area. The National Weather Service (NWS) has announced a flood warning as the outburst of glacial water begins to flow into the Mendenhall River, alarming local officials and residents alike.
After several days of anticipating potential evacuations, city officials confirmed that the melting glacier's dam is compromised, which could result in unprecedented flooding conditions. Located about 12 miles (19 km) from Juneau, the glacier is a notable site for tourists and outdoor enthusiasts.
As of Tuesday, water levels recorded were at 9.85 feet (3 meters), below the critical flooding threshold of 14 feet. However, measurements by Wednesday morning had escalated above 16 feet, an alarming mark that is viewed as a potential record-breaking flood crest, according to meteorologist Nicole Ferrin from the weather service.
The city of Juneau has detailed on its website that glacial lake outburst floods occur when accumulated meltwater is suddenly released, much like removing a plug from a flooded bathtub. This phenomenon happens when the water rises sufficiently to overflow the glacier that holds it back.
In light of the imminent flooding threat, Alaska Governor Mike Dunleavy declared a state of disaster on Sunday. This measure is in response to what officials describe as an "imminent threat of catastrophic flooding," particularly from the glacial lake outburst. Since 2011, flooding has been an ongoing concern in the region, leading to damage and loss of homes.
Experts have noted that rising global temperatures are contributing to the melting of mountain glaciers worldwide, resulting in the formation of glacial lakes. As these lakes increase in number and volume, the risk of sudden dam failures becomes higher, posing flood threats. Scientists predict that climate change may lead to a rise in the frequency of such outburst floods, complicating the understanding of both past and future events.
