Collaborative Research: Refining Long-term Climate Records from the Renland Ice Cap

该计划旨在钻探、分析和解释格陵兰岛东北海岸Renland冰帽的新冰芯。该项目是美国科学家之间的合作项目，哥本哈根大学丹麦冰与气候研究中心和德国阿尔弗雷德·韦格纳研究所。这里描述的美国的努力将集中在气体浓度和气体同位素（Sowers，宾夕法尼亚州立大学）和冰同位素（白色，美国。科罗拉多）。丹麦合作伙伴还将重点关注冰和气体成分的稳定同位素，以及高分辨率化学。德国合作伙伴将专注于冰的物理特性，线扫描和介电特性，以研究推动雪致密化和冰芯年龄模型开发的因素。将在这一国际框架内检索和处理冰芯。考虑到Renland冰帽可能包含比Eemian更古老的冰，堪萨斯大学的CReSIS小组将于2014年夏天在Renland冰帽上空执行一项极高分辨率的无线电回声探测（RES）使命，以帮助指导2015年钻探项目的选址。 伦兰是一个重要的冰芯位置，因为它是冷的（罕见的融化层），受地形的限制，使它不能显着改变海拔，包含冰从末次冰期（可能是Eemian时期），并没有被主要的格陵兰冰盖。没有海拔变化意味着Renland的同位素温度和总空气含量记录可以作为气候标准，与其他格陵兰冰芯进行比较。伦兰冰帽大约有400米厚，所以它不包含易碎的冰。这些特性将使我们能够在绘制和限制格陵兰气候条件方面取得重大的科学进展，特别是在全新世。由于其他格陵兰冰芯质量差，脆冰的出现限制了我们重建高分辨率气候记录的能力。 Renland冰芯将提供重建温室气体记录，火山活动，生物质燃烧事件以及整个全新世海冰范围等关键反馈机制的手段。该项目的主要目标是：（1）将格陵兰岛过去十年中最近出现的快速变暖与过去几个世纪的基线记录以及更广泛的全新世记录联系起来;（2）提供来自格陵兰岛核心的整个全新世的高质量气体记录，以测试目前关于早期人类活动可能如何影响温室气体成分的理论; 3）提供一个超高分辨率的同位素温度记录，与格陵兰岛东部附近的海冰紧密相连，以及该地区的气候历史，希望可以追溯到最后一个间冰期。该项目将提供重要数据，让公众和决策者了解地球气候以及气候变化的原因。该项目提议将格陵兰东部海冰记录以及气候记录纳入自然变化的范围，并进一步了解北极温度和海冰最近的快速变化。该项目将支持研究生和本科生。

This proposal seeks to drill, analyze, and interpret a new ice core from the Renland Ice Cap on the north east coast of Greenland. The project is a collaborative venture between scientists from the U.S., Denmark's Center for Ice and Climate at the Univ. of Copenhagen and Germany's Alfred Wegner Institute. U.S. efforts described here will focus on gas concentrations and gas isotopes (Sowers, Penn State) and ice isotopes (White, U. Colorado). Danish partners will also focus on stable isotopes of ice and gas composition, as well as high-resolution chemistry. German partners will focus on physical properties of the ice, line scanning and dielectric properties to investigate the factors driving snow densification and ice core age model development. Ice cores will be retrieved and processed within this international framework. Given the distinct possibility that the Renland ice cap will contain ice even older than the Eemian, an extremely high resolution Radio Echo Sounding (RES) mission will be flown by the CReSIS group at the Univ. of Kansas over the Renland Ice Cap in the summer of 2014, in order to help guide site selection for the 2015 drill project. Renland is an important location for an ice core as it is cold (infrequent melt layers), constrained by topography so that it cannot significantly change in elevation, contains ice from the last glacial period (and possibly the Eemian period), and has not been overrun by the main Greenland ice sheet. The lack of elevation change means that Renland's isotopic temperature and total air content records can be used as climate standards against which to compare other Greenland ice cores. The Renland ice cap is about 400 meters thick so it does not contain brittle ice. These properties will allow significant scientific progress to be made in mapping out and constraining Greenland climatic conditions in general, but especially for the Holocene. The occurrence of brittle ice in other Greenland ice cores has limited our ability to reconstruct high-resolution climate records due to poor core quality. The Renland ice core will provide the means of reconstructing greenhouse gas records, volcanic activity, biomass burning events, as well as key feedback mechanisms such as sea ice extent throughout the Holocene. Primary objectives of this project are: 1) link the recent, rapid warming seen in Greenland over the past decade to the baseline record of the past few centuries, as well as the broader Holocene record; 2) provide high-quality gas records throughout the Holocene from a Greenland core to test current theories about the how early human activity may have impacted the greenhouse gas composition; 3) provide an ultra-high resolution isotopic temperature record that is tightly coupled to sea ice near eastern Greenland, as well as a history of climate in this region hopefully extending back into the last interglacial period. This project will provide important data to inform the public, and policy makers, about the earth's climate and what causes changes in that climate. This project proposes to place both the records of sea ice off eastern Greenland, as well as the climate record, into the context of natural variability, and further understanding of recent rapid changes in Arctic temperatures and sea ice. The project will support graduate and undergraduate students.