This image of the Ötztal Alps in Austria’s Tyrol was produced with data from the Copernicus Sentinel-2A satellite but comes with an optical illusion thanks to the shadows across the image. The valleys – the green areas – look like they stand higher than the light blue mountains. Snow appears in shades of blue in this unusual false-colour image using light in the near- and shortwave infrared part of the spectrum. This colouring makes it easier to distinguish between snow and vegetation. It also allows us to differentiate between clouds and snow, which is difficult in other parts of the spectrum as they are usually both white. But there are no clouds visible in this image to demonstrate the effect.
In the upper left is the Inn River, flowing east from the Swiss Alps and through Austria and Germany before entering the Danube (not pictured). The land in the Inn river valley and other river valleys appear green with patches of agriculture.
The highest peak in the Ötztal range is Wildspitze, standing over 3770 metres. The mountain is visible in the lower-left corner, east of the elongated lake, Gepatschspeicher.
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