Collaborative Research: Holocene/Deglacial Abrupt Climate Change and Variability of the Western Pacific Warm Pool from Multi-decadal to Century-scale Coral Climate Records

根据该奖项，PI 将使用来自所罗门群岛西部和巴布亚新几内亚东部的珊瑚化石来重建高分辨率全新世/冰消期古气候记录。 该研究区域位于西太平洋暖池（WPWP）的中心附近，该区域是行星气候系统的热力发动机，也是大气中水蒸气的主要来源。 对仪器记录的研究表明，WPWP 的热力和水文特性的变化会对全球海洋和大气产生影响。 该项目将通过化石珊瑚中的配对同位素（?18O）和元素比（Sr/Ca、Mg/Ca、U/Ca）测定，生成 WPWP 中热力和水文变化的月度解析、数十年至世纪尺度的代理记录。 这些地球化学测定将在使用岩相学和矿物学标准评估珊瑚化石样本的潜在成岩蚀变，并通过 TIMS U 系列分析精确测定年代后进行。 珊瑚代理气候记录将用于 1) 识别和定义 WPWP 中全新世/冰消期气候突变和极端的时间和幅度，并确定热带突变与先前定义的热带外突变间隔之间的关系； 2) 确定 WPWP 热带地区平均气候状态的变化如何影响全新世期间年际至百年时间尺度上热带气候变率的性质。

Under this award the PIs will use fossil corals from the western Solomon Islands and eastern Papua New Guinea to reconstruct high-resolution Holocene/ Deglacial paleoclimate records. The study area is located near the heart of the Western Pacific Warm Pool (WPWP), a region that serves as the heat engine of the planetary climate system and a primary source of water vapor to the atmosphere. Studies of the instrumental record show that variations in the thermal and hydrologic properties of the WPWP have global ocean and atmospheric ramifications. This project would generate monthly resolved, multidecadal to century-scale proxy records of thermal and hydrologic variability in the WPWP via paired isotopic (?18O) and elemental ratio (Sr/Ca, Mg/Ca, U/Ca) determinations in fossil corals. These geochemical determinations will be made after the fossil coral samples have been evaluated for potential diagenetic alteration using petrography and mineralogy criteria and after they have been precisely dated by TIMS U-series analysis. The coral proxy climate records will be used to 1) identify and define the timing and magnitude of abrupt transitions and extremes in Holocene/Deglacial climate in the WPWP and determine how abrupt changes in the tropics are related to previously defined intervals of abrupt change in the extra-tropics; and 2) determine how changes in the mean climate state of the WPWP tropical region influence the nature of tropical climate variability on interannual to centennial timescales during the Holocene.