The Late Miocene Climate Enigma: Insights from Expedition 363

就全球气温而言，2016年是破纪录的一年。高温是大气二氧化碳浓度升高和强烈厄尔尼诺事件的全球影响共同作用的结果。气候系统有许多重要组成部分，厄尔尼诺现象表明了低纬太平洋的重要性。西太平洋的暖水池并不总是具有与今天相同的特征，有人提出，它在过去1500万年的演变对全球气候产生了重大影响。为了了解暖池可能如何应对未来的气候变化，重要的是了解其过去演变背后的驱动因素。它只是对随时间变化的海洋盆地的形状做出了反应吗？或者它对气候系统的其他组成部分做出了反应，例如海平面或纬度温度梯度？暖池结构的变化也可能影响了生物生态系统，从而影响了该地区的碳循环。碳循环是地球气候系统的另一个关键组成部分。要了解太平洋暖池这些长期变化的原因和后果，需要双管齐下，结合气候系统不同部分的代理记录进行建模。这项建议旨在生成一些过去高纬度温度和冰量的关键记录，这些记录可以直接与暖池随时间的变化进行比较。这些记录将来自国际海洋发现计划(IODP)收集的微观海洋化石的地球化学分析。

2016 has been a record breaking year in terms of global temperatures. The high temperatures have resulted from a combination of elevated atmospheric pCO2 coupled with the global impacts of a strong El Nino event. There are many important components of the climate system, and the El Nino phenomenon demonstrates the importance of the low latitude Pacific Ocean. The warm pool of water in the western Pacific Ocean has not always had the same characteristics as it has today, and it has been proposed that its evolution over the past 15 million years has had a major impact on global climate. In order to understand how the warm pool might respond to future climate change, it is important to understand the drivers behind its past evolution. Did it respond simply to the changing shape of ocean basins through time? Or did it respond to other components of the climate system, such as sea level or latitudinal temperature gradients? The changes in warm pool structure may also have impacted the biological ecosystems, and hence the cycling of carbon in this region. The carbon cycle is another key component of the Earth's climate system. Understanding the causes and consequences of these long-term changes in the Pacific warm pool requires a two-pronged approach, using modelling in conjunction with proxy records for different parts of the climate system. This proposal aims to generate some key records of past high latitude temperature and ice volume that can be directly compared with changes in the warm pool through time. These records will be derived from geochemical analyses of microscopic marine fossils collected by the International Ocean Discovery Program (IODP).