My friend Seymour Laxon, who has died aged 49 after sustaining a head injury during a fall, was an internationally respected Earth scientist. Seymour used satellites to observe the polar ice caps and the focus of his research was sea ice, a key factor in understanding the global climate since it acts as a barrier to heat and moisture exchange between the ocean and the atmosphere.
Seymour was the only child of Veronica, a psychology lecturer, and Bill, a civil engineer and pioneer of computer-aided design. Inheriting his father's interest in computers, as a teenager Seymour was one of the generation who cut their teeth programming the first home computers in the early 1980s.
He studied physics and astronomy at University College London, where his neat and structured lecture notes showed a clear and well-organised mind at work. It was no surprise when he went on to undertake a PhD at UCL's Mullard Space Science Laboratory in Surrey. There, he met his partner of 19 years Fiona Strawbridge.
Seymour's scientific breakthrough was to distinguish the ice surface from the water surface in satellite radar altimeter measurements of ice-covered oceans. This led to the first detailed map of the Arctic gravity field, revealing new tectonic features beneath the seafloor, and water circulation beneath the ice. His work helped give the European Space Agency the confidence to build CryoSat, a satellite dedicated to observing the Earth's ice-covered regions, launched in 2010.
Seymour taught at UCL's department of space and climate physics, before moving to the department of Earth sciences, where he was director of the Centre for Polar Observation and Modelling. He was awarded his chair in climate physics in 2012.
He approached his work, as he did his life, with energy, integrity and good humour. With the generosity to share his knowledge and encourage others, he built a strong research team of well-trained and motivated young people who will continue his work.
Seymour was sociable and popular. Although brought up a city boy in north London, he loved the great outdoors and enjoyed cycling, camping and hillwalking. Outside work, his proudest achievement was his daughter, Imogen.
He is survived by Fiona and Imogen, and his mother, Veronica.