He is best known for his work on sea ice.
The other four species can live on the sea ice.
Everything you ever wanted to know about sea ice but were afraid to ask.
In September, the area covered by sea ice reached a record low.
He worked on the sea ice, and was therefore packing up to go home.
The area covered by sea ice ranges between 9 and 12 million km2.
In recent years the extent of the sea ice has declined.
Sea ice in the Arctic has two main effects on the weather.
These were built and used during hunting trips, often on open sea ice.
He was killed by the other hunters who convinced him to go on the sea ice.
