Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core

1043500/苗木该奖项支持一个开发50年分辨率甲烷数据集的项目，该数据集将在开发世界气候信息系统分水岭的时间尺度中发挥关键作用，并为比较格陵兰岛和南极洲西部的气候记录提供一个共同的地层框架。对关键间隔提出了更高分辨率的数据，以帮助精确确定两个半球之间气候突变的阶段性。还建议同时分析过去11万年来WAIS分水岭和GISP-2岩心的一组样本，以建立极间甲烷(CH4)梯度，该梯度将用于确定与气候有关的甲烷排放变化的地理区域。这项拟议工作的学术价值在于，它将提供必要的时间控制，以检查气候指标的变化时间，以及通过甲烷变化与格陵兰冰芯记录的关键时间联系。一个主要目标是了解千年尺度气候变化的极间时机。这是一个重要的科学目标，与从总体上理解气候变化机制有关。拟议的工作将有助于建立一个按时间顺序处理这些问题的框架。此外，这项建议通过极间甲烷梯度的工作，解决了冰河时代哪些甲烷源活跃的问题。这项工作针对的是生物圈的哪个部分控制着过去的甲烷变化这一根本问题，这对于发展对这些变化的更复杂的理解是重要的。这项工作的更广泛影响是，超高分辨率的CH4记录将直接惠及所有冰芯古气候研究，而年代学的修正将影响依赖冰芯时间尺度进行对比的古气候研究。该项目将为研究生和本科生提供支持，私人投资促进机构将参与与公众的接触。

1043500/SowersThis award supports a project to develop a 50 yr resolution methane data set that will play a pivotal role in developing the WAIS Divide timescale as well as providing a common stratigraphic framework for comparing climate records from Greenland and West Antarctica. Even higher resolution data are proposed for key intervals to assist in precisely defining the phasing of abrupt climate change between the hemispheres. Concurrent analysis of a suit of samples from both the WAIS Divide and GISP-2 cores throughout the last 110,000 years is also proposed, to establish the interpolar methan (CH4) gradient that will be used to identify geographic areas responsible for the climate related methane emission changes. The intellectual merit of the proposed work is that it will provide chronological control needed to examine the timing of changes in climate proxies, and critical chronological ties to the Greenland ice core records via methane variations. One main objective is to understand the interpolar timing of millennial-scale climate change. This is an important scientific goal relevant to understanding climate change mechanisms in general. The proposed work will help establish a chronological framework for addressing these issues. In addition, this proposal addresses the question of what methane sources were active during the ice age, through the work on the interpolar methane gradient. This work is directed at the fundamental question of what part of the biosphere controlled past methane variations, and is important for developing more sophisticated understanding of those variations. The broader impacts of the work are that the ultra-high resolution CH4 record will directly benefit all ice core paleoclimate research and the chronological refinements will impact paleoclimate studies that rely on ice core timescales for correlation purposes. The project will support both graduate and undergraduate students and the PIs will participate in outreach to the public.