Monday, May 14, 2012

All's well that begins well

We are officially en route to the central tropical Pacific, where we will collect modern and fossil corals, rainwaters, and seawaters in support of our paleoclimate reconstructions from this area. The field team includes Postdoctoral Fellow Jess Conroy, University of Arizona graduate student Diane Thompson, Georgia Tech graduate student Hussein Sayani, and undergraduate research fellow Elizabeth Wiggins. We are especially lucky that Hussein and Liz will be with us on the weekly flight to Christmas Island tomorrow, considering that their tickets to Honolulu apparently didn’t exist when we went to check in this morning! One occasion that money (and a lot of luck) can buy you happiness. Many thanks to the kind folks at Delta, and to the hundreds of ATL passengers waiting at security that we cut in front of to get Hussein and Liz on their flight. There’s never a dull moment launching an expedition, in my experience.

Here are some maps of our destination - Christmas Island (2N, 157W).
Googlemap of Christmas Island (2N, 157W)

Why Christmas Island? Christmas is located in the very middle of the Pacific Ocean, at the heart of the El Nino-Southern Oscillation, a far-reaching source of year-to-year global climate variability. Warmer-than-average sea-surface temperatures associated with El Nino events cause widespread flooding along the western coast of the Americas and bring drought to many areas in and around the western tropical Pacific. La Nina cool extremes have largely the opposite effects. As high-quality instrumental records of climate in this region only extend back 60 years or so, our lab has generated multiple coral-based reconstructions that extend back many centuries. These records contain a rich history of central tropical Pacific climate variability, capturing El Nino-Southern Oscillation extremes, natural decadal-scale variability, as well as late 20th century trends associated with anthropogenic climate change. Such records are constructed from so-called “fossil” corals, found lying on beaches at Christmas and neighboring islands. We calibrate the oxygen isotopic-based climate signal in the corals using “modern” corals collected via SCUBA. On this trip we will collect hundreds (thousands?!?) of small fossil coral samples and several modern coral cores. The second major objective of this trip is to collect dozens of rainwater and seawater samples for oxygen isotopic analysis, and set up a long-term water collection program on the island. Such data will help us understand how regional temperature and rainfall changes are recorded in the oxygen isotopic variations of the island’s corals. We will be posting more detailed explanations of each of our scientific objectives as we tackle them. Hopefully this morning’s antics are not a prelude of things to come, but in my experience fieldwork is full of surprises, both good and bad.