Mendenhall Glacier
Southeast Alaska contains Alaska's two largest icefields: Juneau Icefield and Stikine Icefield, both straddling mountain ranges extending into British Columbia. Mendenhall Glacier is on the southwest side of the Juneau Icefield. It was formed about 3,000 years ago in the Neoglacial of the Late Cenozoic Ice Age and reached its maximum during the relatively recent Little Ice Age. In the last 233 years, this glacier receded 2.5 miles. Our guides told us that the glacier is now 12 miles long and terminates in Mendenhall Lake. It begins on the western snowfields of the Taku Range"at an elevation of 5,500 feet and flows down to 100 feet above sea level just outside the city. The glacier is over 200 feet thick at its terminus, with more than 100 feet poking above the water and another 100 feet below the water's surface. The glacier flows at a rate of about 2 feet per day.
To get to Mendenhall Glacier by air, we climbed aboard a helicopter at the airport -- next to the Gastineau Channel, which was carved out by ice along a fault line. Over Mendenhall Lake, near the terminus of the glacier, we saw a waterfall pouring forth from between Heintzleman Ridge and Bullard Mountain.
Our pilot then flew us over Suicide Icefall. This is formed from another glacier flowing off the Juneau Icefield between Mendenhall Towers and Wrather Mountain . We flew around the lower end of the glacier before landing near Suicide Icefall. Crevasses abound and reveal deep cuts into the surface (our guides said some have been found which are 120 feet deep). We also saw moulins -- these are entrances where water flows into the glacier (which is apparently honeycombed with water channels). Some of these angle into the glacier -- others go straight down!
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looking northeast towards the glacier field |
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(route for water inside the glacier) |
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