technology

No, you’re not tripping – this really is a glacier


The Malaspina glacier in Alaska (Picture: Wanmei Liang/Nasa)

Here’s a glacier as you’ve never seen it before, its usual white and blue hues replaced by a psychedelic rainbow.

This trippy view of the Malaspina glacier on the southeastern coast of Alaska was taken by Nasa’s OLI-2 (Operational Land Imager-2) on Landsat 9 on October 27.

By capturing the image in infrared, all is not as it seems. Water and icy features are a glorious array of reds, oranges and yellows. Vegetation is green, and grey old rock is transformed into blue.

The Malaspina glacier, known as Sít’ Tlein, or ‘big glacier’ in Tlingit, is around 1,680 square miles in size, sprawling across Alaska’s Wrangell-St Elias National Park.

It is also the world’s largest piedmont glacier, a rare phenomenon when the ice from a mountain or valley glacier spreads out as a huge lobe over flat terrain.

The Malaspina glacier is fed by the Seward glacier, and covers an area bigger than Luxembourg.

The Malaspina glacier in 2014, and in October as seen in infrared (Picture: Wanmei Liang/Nasa)

The dark blue-purple lines seen on the ice are moraines, areas where rock, soil and other debris have been scraped up by the glacier on its long, slow march towards the sea and dropped along its edges.

The zigzag pattern is caused by its uneven movement. Glaciers in this region of Alaska typically surge forward for one to several years at a time, before slowing down again.

Because of this irregular flow, the moraines can fold, compress, and shear to form the characteristic textures seen on Malaspina.

The Malaspina glacier viewed from over land, looking out to sea (Picture: Getty/iStockphoto)

At the end of the glacier, the terminus, a thin strip of land is holding back the ice from the Gulf of Alaska.

A comparison of satellite imagery over time has revealed a lagoon system forming along that barrier over the past few decades, particularly in the bottom right of the image. 

The Malaspina glacier, in southeastern Alaska (Picture: Metro.co.uk)

Small patches of open water are visible in a rusty red colour. Some of this water is nearly as salty as the ocean, according to recent research, meaning that comparatively warm ocean water is making contact with the ice. 

This could lead to large-scale calving and hasten the glacier’s retreat.


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