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First Landsat 8 images of Antarctica

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Acquisition of optical satellite imagery is strongly dependent on seasons. When Landsat 8 started operations in May it was spring on the northern Hemisphere and autumn in the south. As a result only very few late autumn images were taken before the start of the polar night in Antarctica. But now the 2013/2014 summer season has started and the first new images are becoming available. The following samples are from a scene at the southern edge of the regular Landsat coverage in the Transantarctic Mountains.

Nimrod Glacier

The large glacier that can be seen in the middle is the Nimrod Glacier which is one of the large glaciers cutting through the Transantarctic mountains and draining the East Antarctic ice sheet. The whole area can be seen on this map. The satellite image is in polar stereographic projection with south up at this point just like in my Antarctica map. The top left edge marks the edge of the regular Landsat coverage although there could be images taken from further south in the future as it has been done in the north previously. Where the glacier descends more than 1000m from the edge of the plateau on the upper right to the Ross Ice Shelf on the lower left there is a small rock area directly in the middle of the glacier called the Kon-Tiki Nunatak which can be seen in larger in the following crop.

Kon-Tiki Nunatak

At this time of the year temperatures are still way below zero so no snow has melted but precipitation is low in the Antarctic interior so there are significant areas free of snow and ice throughout the year like this rock slope at the northern side of the glacier. This is also approximately the edge of the Ice Shelf, that is where the glacier has reached sea level and is starting to float on the ocean water – several hundred kilometers from the open ocean.

Cambrian Bluff

One of the major forces influencing the Antarctic landscape is the wind and how it distributes the snow. This can be seen especially on the heights of the east Antarctic plateau where snow accumulates on the leeward sides of the mountains and strongly exposed ice surfaces are free of snow and appear blue as in the lower right of the following crop.

East Antarctic Plateau

As can be seen in the images the sun in still very low in early spring leading to long shadows. The good dynamic range of the Landsat 8 data offers great shadow detail though. This means structures in the shadows only illuminated by indirect lighting are well visible.

Nash Range

The original scene can be obtained for free at the USGS as well as a growing selection of further new images from other parts of Antarctica.

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