The rain did not relent for our last day in Anchorage, though it also did not stifle a scenic drive to Chugach National Forest along the Cook Inlet. After arriving at the forest’s visitor center, Ellen, Dima, Elliot, Kelsey, and I trekked to the foot of the Portage Glacier. Dima, our resident glacier expert, explained how the moving ice forms were responsible for carving out U-shaped valleys. He also described the process that is responsible for the blue shades of glacial ice: as snow and ice accumulate, the ice beneath becomes compacted, and air is effectively “squeezed out.” This dense ice absorbs light more readily in the red and yellow spectrum, reflecting the blue light we are able to see. Ice on the surface of glaciers – as well as snow in general – tend to reflect light of across the visible spectrum. Dima spent time coring glaciers in Russia, and explained that years can be distinguished within compacted ice by the sediment that accumulates during warmer months.
This iceberg arrived in front of the Visitor's Center after breaking off of the Portage Glacier on July 25. It is estimated to weigh over 275,000 lbs, and only 10% of the iceberg is visible.
I learned today that permafrost does not necessarily occur under all glaciers. The Portage Glacier, for example, is responsible for a good deal of runoff during spring and summer months. This means that water travels underneath the entirety of the glacier, keeping the soil below above freezing. Some “cold glaciers” are frozen all the way to the soil beneath, providing conditions suitable for permafrost to form. Who would have thought all glaciers weren’t “cold?”
The Schwarz Flag displayed on the Portage Glacier.
Before heading back to Anchorage proper, we took a jot to the other side of town to visit the Alaska Native Heritage Center. The non-profit organization provides a wealth of knowledge regarding the unique histories, traditions, and current practices of Native Alaskan cultures. Among the most memorable components of the center are dwellings made in the style of different Native Alaskan peoples.
This dwelling, typical of indigenous peoples in Southeast Alaska, is made largely of red and yellow cedar. The side panels will swell in the wet winter months to create tightly closed, well insulated walls. In the drier summers, the wood panels will separate slightly, allowing for ventilation.
Artists representing the Eyak, Tlingit, Haida, & Tsimshian peoples of Southeast Alaska, were busy creating beautiful house poles from large cedar trunks.
An artist from Southeast Alaska puts finishing touches on a house pole that will become part of an ongoing exhibit. The artists carve the curved back out of each cedar trunk to help prevent splitting in the wood.
The Heritage Center indicated that the Inupiaq are the Native Alaskans who traditionally call the North Slope home. While seemingly barren to the outsider, literature in the Center described the effective use of animal resources to overcome harsh weather. Whalebones, for instance, are apparently used in the frames of traditional houses. While modern Inupiaq people are certainly privy to present-day technologies, I will be interested to see the geography in which they have thrived for so long.
‘Til tomorrow,
Josh