1. Earth Research Institute; University of California, Santa Barbara; Santa Barbara CA 93106-3060 USA
2. Department of Geography; University of California, Los Angeles; Los Angeles CA 90095 USA
3. Marine Science Institute; University of California, Santa Barbara; Santa Barbara CA 93106-3060 USA
4. Earth Research Institute and Department of Geography; University of California, Santa Barbara; Santa Barbara CA 93106-3060 USA