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

1043500/Sowers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WAIS分水岭时间尺度方面发挥关键作用，并为比较格陵兰岛和南极洲西部的气候记录提供共同的地层框架。还建议在关键间隔期提供更高分辨率的数据，以协助精确确定两半球之间气候突变的阶段。同时分析一套样品从两个WAIS分水岭和GISP-2核心在过去的110，000年，也提出了建立极间甲烷（CH 4）梯度，将用于确定地理区域负责气候相关的甲烷排放变化。拟议工作的智力价值在于，它将提供检查气候代理变化时间所需的时间控制，以及通过甲烷变化与格陵兰冰芯记录的关键时间关系。一个主要目标是了解千年尺度气候变化的两极间时间。这是一个重要的科学目标，关系到对一般气候变化机制的理解。拟议的工作将有助于为解决这些问题建立一个按时间顺序排列的框架。此外，该提案通过对极间甲烷梯度的研究，解决了冰河时期哪些甲烷源活跃的问题。这项工作针对的是生物圈的哪一部分控制了过去的甲烷变化这一基本问题，对于发展对这些变化的更复杂的理解非常重要。这项工作的更广泛的影响是，超高分辨率的甲烷记录将直接有利于所有冰芯古气候研究，而年代学的改进将影响依赖于冰芯时间尺度进行相关性研究的古气候研究。该项目将支持研究生和本科生，PI将参与对公众的宣传。

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.