1. Australian Antarctic Division, Australian Government, Kingston, Tasmania, Australia
2. University of Tasmania, Hobart, Tasmania, Australia
3. Arctic and Antarctic Research Institute, St. Petersburg, Russia
4. The University of Texas at Dallas, Richardson, Texas
5. Casaccia research Centre, ENEA, Rome, Italy
6. Brindisi Research Centre, ENEA, Brindisi, Italy
7. University of Houston, Houston, Texas