Late Quaternary Sea Ice History of the Beringian Arctic Gateway

白令海峡北极门户的晚第四纪海冰历史

• 批准号: 1023537
• 负责人: Julie Brigham-Grette
• 金额: $ 50.95万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1023537&HistoricalAwards=false
• 关键词: Late; Quaternary; Sea; Ice; History

Sea ice extent in the Arctic Ocean and its marginal seas is a key component of the coupled ice-atmosphere-ocean system and a driver of meridional ocean circulation, yet information about sea ice conditions in the past is very limited. The goals of this proposed study are two-fold. The first is to use archived surface sediments collected from the Bering and Chukchi Seas to develop quantitative measures of seasonal sea-ice extent and duration. This will be achieved through analysis of diatom morphology, assemblages and the IP25 biomarker of ice-associated diatoms from a suite of over 200 surface sediments collected from the Bering and Chukchi Seas spanning 0-12 months/year of sea ice. The second goal is to apply sea ice reconstructions using the calibrated diatom assemblage methods and IP25 analysis to a suite of six archived cores that form a latitudinal transect through the Bering and Chukchi Seas. The PIs aim to quantitatively reconstruct Late Pleistocene and Holocene seasonal sea ice extent at centennial-scale resolution. These efforts will be corroborated with independent biomarker-based evaluation of surface water temperatures. The successful completion of the project will result in a rich, multi-proxy data set that will be used to evaluate the sea ice and sea surface temperature history of the Bering Strait region. The results of this project will be relevant to global climate modelers as well as paleoecologists, paleoclimatologists, and paleoceanographers interested in regional- to global-scale forcing issues. The broader Arctic science community would benefit from the proxy development proposed. The project would support two full-time graduate students and a summer undergraduate research assistant in each year of the project. The PIs and students will also continue to develop curriculum modules designed to introduce 5th through 8th grade students to the topics of global and Arctic climate, marine sedimentation, ecosystem adaptation to changing environments, and the classification of organisms.

北冰洋及其边缘海的海冰范围是冰-大气-海洋耦合系统的关键组成部分，也是经向海洋环流的驱动因素，但过去有关海冰状况的信息非常有限。这项拟议研究的目标有两个。第一个是利用从白令海和楚科奇海收集的存档表面沉积物来定量测量季节性海冰的范围和持续时间。这将通过对白令海和楚科奇海跨越 0-12 个月/年海冰收集的 200 多种表面沉积物中的硅藻形态、组合和与冰相关的硅藻的 IP25 生物标志物进行分析来实现。第二个目标是使用校准的硅藻组合方法和 IP25 分析对形成穿过白令海和楚科奇海的纬度横断面的一组六个存档核心进行海冰重建。 PI 旨在以百年尺度的分辨率定量重建晚更新世和全新世季节性海冰范围。这些努力将得到基于独立生物标记的地表水温评估的证实。该项目的成功完成将产生丰富的多代理数据集，用于评估白令海峡地区的海冰和海面温度历史。该项目的结果将与全球气候建模者以及对区域到全球范围的强迫问题感兴趣的古生态学家、古气候学家和古海洋学家相关。更广泛的北极科学界将受益于拟议的代理开发。该项目每年将支持两名全日制研究生和一名暑期本科生研究助理。 PI 和学生还将继续开发课程模块，旨在向 5 至 8 年级学生介绍全球和北极气候、海洋沉积、生态系统适应不断变化的环境以及生物体分类等主题。