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

合作研究：完善伦兰冰盖的长期气候记录

• 批准号: 1304109
• 负责人: James White
• 金额: $ 47.49万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-11-01 至 2017-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1304109&HistoricalAwards=false
• 关键词: Collaborative; Research; Refining; Long; term; Collaborative; Research; Refining; Long; term

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.

该提案旨在从格陵兰东北海岸的伦德兰冰盖进行钻，分析和解释新的冰芯。该项目是美国科学家，丹麦大学冰与气候中心之间的合作企业。哥本哈根和德国的阿尔弗雷德·韦格纳学院（Alfred Wegner Institute）此处描述的美国努力将重点放在气体浓度和气体同位素（Sowers，Penn State）和ICE同位素（White，U。Colorado）上。丹麦伙伴还将专注于冰和气体组成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，线扫描和介电特性的物理特性，以研究驱动雪致密化和冰核年龄模型开发的因素。将在此国际框架内检索和处理冰芯。鉴于Renland冰盖的可能性明显甚至比EEMIAN更古老，因此，Univ的Cresis Group将驾驶极高的分辨率无线电回声（RES）任务。 2014年夏天，堪萨斯州在伦兰冰盖上的堪萨斯州，以帮助指导2015年钻探项目的现场选择。 Renland是冰芯的重要位置，因为它是冷的（很少经常的熔体层），受地形的约束，因此它无法显着改变海拔，其中包含了最后一个冰川时期（可能是EEMIAN时期），并且没有被主要的Greenland Iceppher所淹没。缺乏海拔变化意味着Renland的同位素温度和总空气含量记录可以用作与其他格陵兰冰芯进行比较的气候标准。 Renland冰盖厚约400米，因此不含脆性冰。这些特性将允许在绘制和限制格陵兰气候条件的绘制和限制格陵兰气候条件方面，尤其是全新世。由于核心质量较差，在其他格陵兰冰块中脆性冰的发生限制了我们重建高分辨率气候记录的能力。 Renland Ice Core将提供重建温室气体记录，火山活动，生物量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）将过去十年中格陵兰岛的最近快速变暖与过去几个世纪的基线记录联系起来，以及更广泛的全新世记录； 2）从格陵兰核心提供高质量的气体记录，以测试当前人类活动如何影响温室气体成分的当前理论； 3）提供超高分辨率的同位素温度记录，该记录紧密耦合到格陵兰东部东部的海冰，以及该地区的气候历史，希望能够延伸到最后一个冰河间时期。该项目将提供重要的数据，以告知公众和政策制定者，了解地球的气候以及导致这种气候变化的原因。该项目建议将海冰的记录置于东格陵兰东部的记录以及气候记录，置于自然变异性的背景下，并进一步了解北极温度和海冰的最近快速变化。该项目将支持毕业生和本科生。