Following the appearance of a large crack in the ice shelf close to the Halley VI research station in Antarctica, information from the Copernicus Sentinel-1 and Sentinel-2 satellites helped to decide to close the base temporarily. Dubbed the ‘Halloween Crack’, this rift was lengthening inland as fast as 600 m a day in November and December. The two Sentinel missions are being used to closely monitor the Halloween Crack, which is now growing at about 200 m a day, two other ice chasms and detect new cracks. See http://www.esa.int/Our_Activities/Observing_the_Earth/Sentinels_warn_of_dangerous_ice_crack
