Geographic location
Alberti
4
Antarctic
4
Chevreux
4
Gulf of Alaska
4
Hurley
4
Indian
Lowry
4
Nagata
4
Pacific
4
Seta
4
Thurston
4
Arctic
2
Austin
2
Baldwin
2
Barbara Island
2
Bering Sea
2
Coleman
2
Greenwich
2
Mid-Atlantic Ridge
2
New Zealand
2
Norwegian Sea
2
Porcupine Seabight
2
Queen Charlotte
2
Signy Island
2
South Orkney Islands
2
Southern Ocean
2