Anthropogenic climate change poses a serious threat to coral reefs around the world. The impacts of global warming can be isolated by studying long-lived corals growing on remote, uninhabited islands of the central tropical Pacific, where human impact is nonexistent—this is what NGS/Waitt grantee Dr. Kim Cobb and her team plan to do. By analyzing the chemistry of large coral skeletons collected from reefs in this area, they can reconstruct the monthly history of temperature and rainfall patterns for the last 50 to 100 years.
Tropical Pacific climate oscillations and trends profoundly affect temperature and rainfall patterns around the world, impacting Atlantic hurricane activity, Indian monsoon strength, and drought in the western U.S. An accurate history of tropical Pacific temperatures and rainfall may help to both explain regional climate trends over the last decades and to improve regional climate forecasts for the coming decades.
They propose to survey coral reef health, install environmental monitoring devices, and collect long coral cores from three equatorial islands—Malden, Starbuck, and Filippo. The team chose to target these three islands because they are heavily impacted by the powerful climate systems that they would like to reconstruct; their location is poorly sampled by available instrumental climate data; and very little scientific research has been conducted there, so much can be gained from this expedition's data. Moreover, there is some urgency to the proposed work, as climate change continues to degrade coral reef health, such that the large, healthy coral colonies we need for our studies may disappear in coming years.