Icelandic Tigers and Von Karman Vortices: Landsat Imagery
Sci-Fi-O-Rama presents Landsat false-colour composite photographs from the United States Geological Survey (USGS) archives. All images are selections from the USGS Landsat series ‘Earth as Art‘.
What is Landsat? Well, the clue is in the name. The Landsat program is a series of Earth-imaging satellites, jointly operated by USGS and NASA. Now on its 8th generation of satellites, the program dates back to 1972 with the launch of Landsat 1. Imagery produced by Landsat is used to study a multitude of topics; disaster relief, forestry conservation, glacial retreat and agricultural forecasting to name only a few.
Landsat’s false-colour images are generated by high-resolution cameras capturing a sequence of black and white photographs at differing wavelengths of light including infra-red. The more light reflected, the brighter the spot in the picture. Three black and white photographs are then selected and coloured either red, green or blue for dramatic effect.
Here then are a selection of alien vistas close to home.
Ghostly Grease Ice
Aland Islands, Northern Baltic Sea.
Grease ice is the early stage of sea ice formation and is seen here in swirling spectral turquoise forming off the coast of the Aland Islands (shown in red). The phenomenon consists of a viscous mix of tiny ice crystals tumbling in a maelstrom of swirling currents and freezing winds.
Canadian High Arctic.
Curtains of heavy snow blow wild across Meighen Island (left of frame) which lays at the northernmost tip of Canada’s icy archipelagos. The fractal maze of blue and yellow are the fjords and glaciers of the much larger Axel Heiberg Island.
These are some of the most remote and inhospitable lands on earth. Indeed, no sign of past human settlement has ever been found on Meighen Island. As wild a place as one could wish to find.
Chukotka Autonomous Okrug, Siberia
This abstract drizzle of snaking lines is, in fact, the Mayn river and its countless tributaries photographed from 438 miles above the earth. The Mayn River is located in Chukotka, an extremely remote and sparsely populated region of far-eastern Siberia.
Alexander Selkirk Island, Chile, South Pacific
Kármán vortices as seen from space. This unusual metrological phenomenon occurs when wind-driven clouds encounter a high mountain and form large swirling eddies as they pass by. In this case, the highest point of the isolated Alexander Selkirk Island (over one mile above sea level) plays disruptor of the South Pacific flow.
Also of interest, Alexander Selkirk Island was renamed from Más Afuera (Further Out) in memory of the Scottish Sailor who was famously marooned there. Selkirk spent four years and four months as a castaway before being rescued, his story would, of course, become the inspiration for Daniel Defoe’s classic ‘Robison Crusoe’.
Utah, United States of America
Utah’s Green River writhes south across the Tavaputs Plateau (top) before descending into Desolation Canyon (centre). This area is one of the largest unprotected wilderness regions of America and the canyon is nearly as deep as the Grand Canyon.
Kamchatka, Far Eastern Russia
Snow-covered volcanic peaks of Kamchatka feed glacial ice into the northern Pacific ocean. Kamchatka is perhaps Russia’s most furthest-flung region, nearer to Seattle than Moscow. It’s a vast area of largely untouched natural splendour and home to one of the most isolated cities on earth, Petropavlovsk-Kamchatsky.
Vatnajokull Glacier Ice Cap
Valley glaciers protrude as icy digits splaying out from Europe’s largest icecap, the Vatnajokull Glacier, in Southern Iceland.
This is an area occasionally prone to a natural phenomenon known as a ‘Jökulhlaup‘, an Icelandic word that literally translates to English as “Glacial Run”. Volcanic activity warms a glacier from the inside creating a reservoir of water within. When the outer wall collapses a raging torrent of water races down the mountainside, violently swallowing anything in its path. Think flash flood on steroids.
Kármán Vortices (2)
Aleutian Islands, Alaska
More Kármán vortices, this time formed as fast-moving clouds and arctic winds sweep south across the Aleutian Islands. This chain of twelve volcanic islands forms the northern rim of the Pacific ‘Ring of Fire’.
Eerie Cloud Shadows
Red clouds cast strange tail-like shadows onto the cobalt blue desert beneath. The dark circles toward the bottom of the image are irrigated fields, each a tiny oasis of life.
While bearing an uncanny resemblance to Cassini imagery of Jupiter’s forever swirling clouds, this image was captured much closer to home. The Dasht-e Kevir, also know as ‘The Great Salt Desert’, is a vast uninhabited wasteland of sand, salt and mud. The extremely high salt concentration stops the moisture from completely evaporating, hence the mud.
Akuyeri, Northern Iceland
And finally we come to my favourite of the bunch, also featured at the top. This Icelandic tiger is a 90 degree rotated view of northern Iceland. Squint your eyes and the tiger’s pelt emerges from the mountainous terrain coloured orange and the snow capped peaks in white. Completing the pareidolia is Eyjafjörður Fjord, standing in for the tiger’s mouth. Iceland’s second largest town, Akuyeri, sits where the upper back teeth might be. Well worth a visit from what I hear…
You can find these and more Landsat imagery at landsat.usgs.gov.