1. School of Mathematics and Statistics University of St Andrews St Andrews Fife KY169AJ UK
2. HiDef Aerial Surveying Ltd, The Observatory Dobies Business Park Lillyhall Cumbria CA14 4HX UK
3. British Antarctic Survey High Cross, Madingley Road Cambridge CB3 0ET UK
4. Ocean and Earth Science, National Oceanography Centre Southampton University of Southampton University Road Southampton SO17 1BJ UK
5. Norwegian Polar Institute Framsenteret, Postboks 6606, Stakkevollan 9296 Tromsø Norway