1. GNS Science, P.O. Box 30‐368, Lower Hutt 5040, New Zealand, R.Langridge@gns.cri.nz
2. The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
3. National Institute of Water and Atmospheric Research, 301 Evans Bay Parade, Wellington 6021, New Zealand
4. School of Earth and Ocean Sciences, Bob Wright Centre A405, University of Victoria, Victoria, British Colombia, Canada V8P 5C2
5. Pacific Gas and Electric Company, P.O. Box 997300, Sacramento, California 95899‐7300
6. University of Southern California, 3651 Trousdale Parkway, Los Angeles, California 90089