Discover more about our planet with the Earth from Space video programme. In this special edition, Anny Cazenave, altimetry specialist and Senior Scientist at the LEGOS research centre (Laboratoire d'Etudes en Géophysique et Océanographie Spatiales) and at the French space agency, CNES, joins us from the '20 Years of Progress in Radar Altimetry Symposium' held in Venice, Italy, 24--29 September.