Earth Observation (EO) satellites circle the Earth carrying instruments looking down on our oceans, land, atmosphere, and ice caps alike.
Image of the Great Barrier Reef taken by Envisat
Different instruments measure different things. For instance, some are able to look through clouds to take the temperature of the seas, building up a global picture of sea surface temperature. Others send signals which bounce back from different depths of cloud providing information on the cloud’s chemical composition.
Often these observations are complemented by measurements taken from the ground or from aircraft to build up a full description of our planet. This wealth of data is proving invaluable to scientists studying our environment, testing current theories and improving predictions of global change. This information is proving useful too for the future management of our environment.