EAPSI:Developing a Coral-Based Climate Reconstruction to Better Understand Tropical Pacific Hydroclimate

起源于热带太平洋的厄尔尼诺Niño-Southern涛动可以引起全球气候和天气模式的重大变化，例如干旱和洪水。在科学文献中，厄尔尼诺Niño-Southern振荡将如何对人为气候变化作出反应仍然没有答案。通过与新西兰国家水与大气研究所（NIWA）的安德鲁·洛雷博士的合作，这项研究将通过收集珊瑚礁样本的化学测量数据来重建过去一千年的气候变化，从而提高对厄尔尼诺Niño和拉尼娜事件的科学认识。洛雷博士是一位气候学家专家，也是南太平洋珊瑚档案馆的馆长。这项研究将在更长的时间内扩展气候观测，使科学家能够将当前的气候变化置于更长的古气候背景中。在热带太平洋西南部，主要的气候特征是低空水汽带，即南太平洋辐合带。在厄尔尼诺Niño事件期间，该区域向赤道移动，导致南太平洋异常干燥，赤道太平洋中部异常潮湿。从南库克群岛收集了100多个珊瑚样本，将用于重建与南太平洋辐合带和El Niño-Southern涛动运动有关的水文变化。保存完好的珊瑚样本将使用x射线计算机断层扫描技术进行放射性定年和年龄建模。珊瑚骨架中的稳定同位素随温度和水文变化而变化。因此，珊瑚可以用来模拟气候变化。为了重建过去一千年的气候，我将与安德鲁·洛雷博士一起对原始的、年代确定的珊瑚样本进行取样，并使用新西兰奥克兰NIWA的仪器，为马里兰大学古气候联合实验室的未来同位素分析准备珊瑚样本。该奖项是与新西兰皇家学会合作资助的。

The El Niño-Southern Oscillation, which originates in the tropical Pacific, can cause significant changes in climate and weather patterns across the globe, such as droughts and floods. How the El Niño-Southern Oscillation will respond to anthropogenic climate change remains unanswered in the scientific literature. Through a collaboration with Dr. Andrew Lorrey of the National Institute of Water and Atmospheric Research (NIWA) in New Zealand, this research will improve the scientific understanding of El Niño and La Nina events by collecting chemical measurements from coral reef samples to reconstruct changes in climate over intervals of the last millennium. Dr. Lorrey is an expert climatologist and curator of a south Pacific coral archive. This study will extend climate observations over a longer period of time allowing scientists to put current climate change into a longer paleoclimate context.In the southwestern tropical Pacific, the dominant climate feature is a band of low-level moisture, known as the South Pacific Convergence Zone. During an El Niño event, this zone shifts towards the equator, resulting in unusually dry conditions in the south Pacific and unusually wet conditions in the central equatorial Pacific. Over 100 coral samples have been collected from the southern Cook Islands and will be used to reconstruct hydrological changes associated with movements of the South Pacific Convergence Zone and the El Niño-Southern Oscillation. Well preserved coral samples will be radiometrically-dated and age-modeled using x-ray computed tomography techniques. Stable isotopes in the coral skeleton vary with temperature and hydrological changes. Therefore, corals can be used to model changes in climate. To reconstruct climate over the past millennium, I will sample pristine, well-dated coral samples with Dr. Andrew Lorrey and use instrumentation at NIWA in Auckland, New Zealand to prepare the coral samples for future isotopic analyses at the Paleoclimate Co-Laboratory at the University of Maryland. This award is funded in collaboration with the Royal Society of New Zealand.