Two decades is a negligible period by the standards of the life of the planet, but how many hurricanes, floods and fires have occurred during this time? How many man-made projects have been implemented, the results of which are visible from space? The answer can be provided by a new version of NASA's Worldview tool, which reflects changes on the Earth's surface since 1999.
The map was created on the basis of observations of the Terra satellite, which was joined in 2002 by its brother Aqua. Power users have been able to see daily data from Terra since 2012, but now it has collected 20 years of readings - the largest, global Earth observation diary in human history. An interesting toy for ordinary people and an extremely useful research tool for scientists.
Santiago Gasso, a NASD researcher, makes this comparison. If in the last century you wanted to look, for example, at clouds off the coast of California, you had to first turn up the meteorological guide to find out the best time to observe. Then leave a request so that during the satellite's flight in this area you will be given a "window" for shooting. Then you would have a physical medium in your hands, the data from which you need to decrypt and print.
Now you can see the same clouds with a few mouse clicks. And immediately compare them with other images, compare with data on air and water temperature, pressure and wind speed. See weather and large-scale anthropogenic phenomena, layering different layers and see the whole situation. An invaluable piggy bank of knowledge about the recent past of our planet is available here.