Collaborative Research: Paleohistory of the Larsen Ice Shelf System: Phase II

合作研究：拉森冰架系统的古历史：第二阶段

• 批准号: 0338220
• 负责人: Scott Ishman
• 金额: --
• 依托单位: Southern Illinois University at Carbondale
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-15 至 2009-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0338220&HistoricalAwards=false
• 关键词: Collaborative; Research; Paleohistory; Larsen; Ice

The Larsen Ice Shelf is the third largest ice shelf in Antarctica and has continued a pattern of catastrophic decay since the mid 1990's. The proposed marine geologic work at the Larsen Ice Shelf builds upon our previous NSF-OPP funding and intends to test the working hypothesis that the Larsen B Ice Shelf system has been a stable component of Antarctica's glacial system since it formed during rising sea levels 10,000 years BP. This conclusion, if supported by observations from our proposed work, is an important first step in establishing the uniqueness and consequences of rapid regional warming currently taking place across the Peninsula. Our previous work in the Larsen A and B embayments has allowed us to recognize the signature of past ice shelf fluctuations and their impact on the oceanographic and biologic environments. We have also overcome many of the limitations of standard radiocarbon dating in Antarctic marine sequences by using variations in the strength of the earth's magnetic field for correlation of sediment records and by using specific organic compounds (instead of bulk sediment) for radiocarbon dating. We intend to pursue these analytical advances and extend our sediment core stratigraphy to areas uncovered by the most recent collapse of the Larsen B Ice Shelf and areas immediately adjacent to the Larsen C Ice Shelf. In addition to the core recovery program, we intend to utilize our unique access to the ice shelf front to continue our observations of the snow/ice stratigraphy, oceanographic character, and ocean floor character. Sediment traps will also be deployed in order to measure the input of debris from glaciers that are now surging in response to the ice shelf collapse. This proposal is a multi-institutional, international (USAP, Italy, and Canada) effort that combines the established expertise in a variety of disciplines and integrates the research plan into the educational efforts of primarily undergraduate institutions but including some graduate education. This is a three-year project with field seasons planned with flexibility in order to accommodate schedules for the RVIB L.M. Gould. The Antarctic Peninsula is undergoing greater warming than almost anywhere on Earth, perhaps associated with human-induced greenhouse effects. Our proposed work contributes to understanding of these changes where they are occurring first and with greatest magnitude and impact upon the environment.

拉尔森冰架是南极洲的第三大冰架，自1990年代中期以来一直在灾难性衰变。 Larsen冰架上提议的海洋地质工作建立在我们以前的NSF-OPP资金基础上，并打算检验工作假设，即Larsen B冰架系统一直是南极洲冰川系统的稳定组成部分，因为它是在上升10,000年bp的上升时形成的。如果我们拟议的工作得到观察的支持，这一结论是确定目前在整个半岛进行快速区域变暖的独特性和后果的重要第一步。我们以前在Larsen A和B胚胎中的工作使我们能够认识到过去的冰架波动的签名及其对海洋学和生物学环境的影响。我们还通过使用地球磁场强度的变化来克服南极海洋序列中标准放射性碳年代的许多局限性，以与沉积物记录相关联，并使用特定的有机化合物（代替体积沉积物）进行放射性碳日期。我们打算追求这些分析的进步，并将沉积物核心地层扩展到由于最近的Larsen B冰架和紧邻Larsen C Ice Beshelf附近的区域所发现的区域。除了核心恢复计划外，我们还打算利用对冰架前线的独特访问，继续观察雪/冰层，海洋学特征和海底特色。还将部署沉积物陷阱，以测量冰川的碎屑输入，这些冰川目前正在响应冰架塌陷而涌现。该提案是一项多机构的国际（USAP，意大利和加拿大）的努力，将既定的专业知识结合在各种学科中，并将研究计划纳入主要是本科机构的教育工作，但包括一些研究生教育。这是一个为期三年的项目，其田野季节计划具有灵活性，以适应Rvib L.M. Gould的时间表。南极半岛比地球上几乎任何地方都经历了更大的变暖，这可能与人类引起的温室作用有关。我们提出的工作有助于理解这些变化的首先发生，并对环境产生最大的影响和影响。