BBC: The EU's Sentinel satellite system has begun monitoring six mighty polar glaciers in near real-time. The sextet - Pine Island and Thwaites in Antarctica; and Jakobshavn, Nioghalvfjerdsfjorden, Zacharae Isstrom and Petermann in Greenland - are major contributors to ongoing sea-level rise. They are thinning and flowing faster, and scientists believe some of them have become unstable. Routine observation should pick up any sudden changes in behaviour. The data is currently being gathered by the...