P2C2: New Zealand Climate in Three Warm Periods

从大气层到南大洋的二氧化碳流量在很大程度上受南半球西风位置的控制。在目前的气候系统中，当这些风转向南方时，南大洋的碳汇减少，这对二氧化碳在大气中积累的速度产生了影响。 该项目旨在从过去的气候状态中提供一个视角，这将有助于了解将气候、大气和海洋环流与二氧化碳积累联系在一起的这些过程的未来。该项目还将有助于了解生物可利用尘埃如何影响南大洋的海洋环流和碳循环，这对全球碳循环有影响。研究人员将通过建立新西兰南岛泥炭地沉积物的气候和环境重建来实现这些目标，重点关注地球最近气候历史上的三个温暖时期。 该项目还将通过参加地球科学教师经验计划（ESTEP）为学生和中学教育工作者提供国际合作的机会。来自纽约和新西兰的中学教师将配对参与研究，并将他们的经验融入课程和补充电影，以吸引学生参与科学。具体而言，该研究项目将建立一系列的气候和环境变化的重建从泥炭地沉积物在新西兰南岛在两个历史温暖时期，早至中期全新世和海洋同位素阶段5e（MIS-5e），并将它们与趋势相比较与当前变暖。研究人员将这些与之前的冰期（MIS-2，-4和-6）进行比较。该项目提供资金，以建立一个年表的核心，从定位良好的泥炭地在新西兰南岛的研究地点，无论是在现代西风场或附近的北方边缘。研究人员将使用有机地球化学和稳定同位素替代方法来重建这些温暖时期的南半球西风。 这些数据将与正在进行的现代水同位素测量、气象观测和GCM模拟相结合，直接将沉积物中的稳定同位素测量结果解释为西风变率的记录。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

The flux of carbon dioxide from the atmosphere to the Southern Ocean is largely controlled by the position of the westerly winds in the Southern Hemisphere. In the present climate system, when these winds shift southwards, the carbon sink in the Southern Ocean is diminished and this has implications for the rate at which carbon dioxide accumulates in the atmosphere. This project aims to provide a perspective from past climate states that will help understand the future of such processes linking climate, atmosphere and ocean circulation and carbon dioxide accumulation. The project will also help to understand how bioavailable dust influences ocean circulation and cycling of carbon in the Southern Ocean, which has implications for the global carbon cycle. The researchers will address these goals by establishing reconstructions of the climate and environment from peatland sediments on the South Island of New Zealand with a focus on three warm periods during Earth's most recent climate history. The project will also provide opportunities for international collaboration for students and secondary school educators by participation in the Experiences for Earth Science Teachers Program (ESTEP). Secondary school teachers from New York and New Zealand will be paired to participate in the research and develop their experiences into curricula and supplemental films to engage their students in science. Specifically, the research project will establish a series of reconstructions of climate and environmental change from peatland sediments on the South Island of New Zealand during two historical warm periods, the early- to mid-Holocene and Marine Isotope Stage 5e (MIS-5e) and compare them with trends associated with current warming. The researchers will compare these with the preceding glacial periods (MIS-2, -4, and -6). This project provides the funds to establish a chronology for cores obtained from well positioned peatlands on New Zealand's South Island at study sites that are either within the modern westerly wind field or near its northern edge. The researchers will use organic geochemical and stable isotope proxy methods to reconstruct Southern Hemisphere westerly winds during these warm periods represented in the chronologies of the cores. These data will be coupled to ongoing measurements of modern water isotopes and meteorological observations and GCM simulations to directly interpret stable isotope measurements from sediments as records of westerly wind variability.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.