Published on 15 February 2019
In this Valentine week, ESA offers us the opportunity to admire some wonderful images that remind us of the beauty and the vulnerability of our planet. The images acquired by satellites in orbit several hundred kilometers above the Earth can sometimes be true works of art, but they are first of all indispensible tools to understand and monitor climate change.
Among the images published in this video by ESA, the following three have been acquired by the Sentinel-2 satellite.
The first is an infrared false colour image of Moorea, the one but largest of the Society Islands in French Polynesia, 17 km north-west of Tahiti. Moorea is a mountainous volcanic island with fertile soil. The image highlights in red the lush vegetation of the island and in turquoise the belt of coral reefs. Coral reefs are among the most fragile ecosystems. They are particularly threatened by pollution, overfishing and the rising ocean temperatures.
The second image shows lake Strobel in a false color composite that highlights the geological structures. This lake is one of the most extraordinary in the world. It lies lost in the middle of a huge desert plateau at the foot of the Andes in Patagonia and despite that, its crystal clear waters are very productive. It is home to some of the largest rainbow trout in the world.
The third image is a representation in real colors of a small part of the Aral Sea (the northern tip of the western part of the large sea). This stretch of water is actually a salt lake straddling Kazakhstan and Uzbekistan. Until the 1950s, it was the 4th largest lake in the world. The diversion of the two main tributaries of the lake in the early 1960s for large-scale irrigation resulted in a dramatic shrinking of the lake. At the end of the 1980s, the Aral Sea split in two: the small sea to the north and the large horseshoe-shaped sea to the south. Since then, the southern part has continued to dry up, with dramatic environmental and economic consequences. The small sea in the north has been doing better since 2005 thanks to the construction of a dam financed in part by the World Bank to prevent the flow of water to the southern part. To visualise the evolution of the Aral Sea, visit the website Earth Observatory - World of Change.