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

厄尔尼诺-南方涛动起源于热带太平洋，可导致地球仪气候和天气模式发生重大变化，如干旱和洪水。厄尔尼诺-南方涛动将如何对人为气候变化作出反应，在科学文献中仍然没有答案。通过与新西兰国家水和大气研究所的Andrew Lorrey博士合作，这项研究将通过收集珊瑚礁样本的化学测量数据来重建上个千年期间的气候变化，从而提高对厄尔尼诺和拉尼娜现象的科学认识。Lorrey博士是一位气候专家，也是南太平洋珊瑚档案馆的馆长。这项研究将把气候观测扩展到更长的时间段，使科学家能够将当前的气候变化纳入更长的古气候背景中。在热带太平洋西南部，主要的气候特征是一条低层水分带，称为南太平洋辐合带。在厄尔尼诺事件期间，这一区域向赤道移动，导致南太平洋异常干燥，赤道太平洋中部异常潮湿。从库克群岛南部采集了100多个珊瑚样本，将用于重建与南太平洋辐合带和厄尔尼诺-南方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年代测定和年龄建模。珊瑚骨骼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·洛里博士一起采集原始的、年代久远的珊瑚样本，并在新西兰奥克兰的NIWA使用仪器，为马里兰州大学古气候联合实验室未来的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.