1. Research School of Earth Sciences; Australian National University; Canberra ACT Australia
2. Antarctic Climate and Ecosystems Cooperative Research Centre; Hobart Tasmania Australia
3. Institute for Marine and Antarctic Studies; University of Tasmania; Hobart Tasmania Australia
4. Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences; University of East Anglia; Norwich UK
5. Department of Chemistry; University of Otago; Dunedin New Zealand
6. Department F.-A. Forel for Environmental and Aquatic Sciences; University of Geneva; Geneva Switzerland
7. National Institute of Water and Atmospheric Research; Wellington New Zealand
8. Institute for Applied Ecology; University of Canberra; Canberra ACT Australia
9. Department of Physics; University of Auckland; Auckland New Zealand
10. Central Science Laboratory; University of Tasmania; Hobart Tasmania Australia
11. Plymouth Marine Laboratory; Plymouth UK
12. Now at Institute for Marine and Antarctic Studies; University of Tasmania; Hobart Tasmania Australia