Modeling the Glacial Evolution of Antarctica and the Paleogene Transition from a "Greenhouse" to "Icehouse" World

模拟南极洲的冰川演化和古近纪从“温室”世界到“冰室”世界的转变

• 批准号: 9905890
• 负责人: Robert DeConto
• 金额: $ 19.74万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9905890&HistoricalAwards=false
• 关键词: Modeling; Glacial; Evolution; Antarctica; Paleogene

The glaciation of East Antarctica and the associated shift to cold condition over high southern latitudes represents the most fundamental reorganization of the global climate-ocean system in the Cenozoic. Determining the mechanisms responsible for the nucleation, development, and periodic fluctuations of the Antarctic ice sheet is important to our understanding of the global climate system and future climatic change. The Cenozoic cooling trend from the warm "greenhouse" climate mode of the Early Eocene, to the "ice house" world of today, has long been recognized in paleontologic, isotopic, and sedimentologic evidence. This award supports designed to answer these question: 1) what long-term paleoenvironmental changes led to the growth of limited Antarctic ice during the mid-Late Eocene and 2) what triggered the rapid growth of the East Antarctic ice sheet in the earliest Oligocene (-33.7 ma). A comprehensive investigation of Late Eocene/Early Oligocene climate echoing, designed to isolate the relative role of possible climate forcing mechanisms and feedbacks in the transition from a "greenhouse" to "icehouse" world, will use the GENESIS Version 2.0 Global Climate Model, interactivity coupled to a predictive vegetation model (IBIS) and asynchronously coupled to a new high resolution dynamical ice sheet model specifically designed for GCM investigations of ice-sheet initiation and development. A systematic series of sensitivity tests will assess the role of atmospheric CO2, orbital parameter, atmosphere-vegetation feedbacks, paleogeography, and ocean heat transport in the initiation and growth of glacial ice on Antarctica.

南极洲东部的冰川和在高南部纬度上的寒冷状况的冰川转变代表了新生代全球气候 - 海洋系统最基本的重组。 确定负责南极冰盖成核，发育和周期性波动的机制对于我们对全球气候系统和未来气候变化的理解至关重要。 从始新世早期的温暖“温室”气候模式到当今的“冰屋”世界的碳融化趋势长期以来一直在古生物学，同位素和沉积学证据中得到认可。 该奖项支持旨在回答以下问题的旨在：1）在中期始新世期间，有限南极冰的长期古环境变化导致有限的南极冰的生长，以及是什么引发了最早的渐新世（最早的渐新世）迅速增长-33.7 mA）。 对始新世晚期/早期渐新世气候的全面调查，旨在隔离从“温室”到“冰屋”世界中可能的气候强迫机制和反馈的相对作用耦合到预测植被模型（IBIS），并异步与新的高分辨率动态冰盖模型耦合，专门针对GCM研究冰层启动和开发。 一系列系统的灵敏度测试将评估大气二氧化碳，轨道参数，大气蔬菜反馈，古地理和海洋热传输在南极洲冰川冰的启动和生长中的作用。