Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition

始新世-渐新世过渡期间南极冰盖生长和海冰形成的时间和空间分布

• 批准号: 1743643
• 负责人: Sandra Passchier
• 金额: $ 32.31万
• 依托单位: Montclair State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1743643&HistoricalAwards=false
• 关键词: Timing; Spatial; Distribution; Antarctic; Ice

Abstract (non-technical)Sea level rise is a problem of global importance and it is increasingly affecting the tens of millions of Americans living along coastlines. The melting of glaciers in mountain areas worldwide in response to global warming is a major cause of sea level rise and increases in nuisance coastal flooding. However, the world's largest land-based ice sheets are situated in the Polar Regions and their response under continued warming is very difficult to predict. One reason for this uncertainty is a lack of observations of ice behavior and melt under conditions of warming, as it is a relatively new global climate state lasting only a few generations so far. Researchers will investigate ice growth on Antarctica under past warm conditions using geological archives embedded in the layers of sand and mud under the sea floor near Antarctica. By peeling back at the layers beneath the seafloor investigators can read the history book of past events affecting the ice sheet. The Antarctic continent on the South Pole, carries the largest ice mass in the world. The investigator's findings will substantially improve scientists understanding of the response of ice sheets to global warming and its effect on sea level rise.Abstract (technical)The melt of land based ice is raising global sea levels with at present only minor contributions from polar ice sheets. However, the future role of polar ice sheets in climate change is one of the most critical uncertainties in predictions of sea level rise around the globe. The respective roles of oceanic and atmospheric greenhouse forcing on ice sheets are poorly addressed with recent measurements of polar climatology, because of the extreme rise in greenhouse forcing the earth is experiencing at this time. Data on the evolution of the West Antarctic ice sheet is particularly sparse. To address the data gap, researchers will reconstruct the timing and spatial distribution of Antarctic ice growth through the last greenhouse to icehouse climate transition around 37 to 33 Ma. They will collect sedimentological and geochemical data on core samples from a high-latitude paleoarchive to trace the shutdown of the chemical weathering system, the onset of glacial erosion, ice rafting, and sea ice development, as East and West Antarctic ice sheets coalesced in the Weddell Sea sector. Their findings will lead to profound increases in the understanding of the role of greenhouse forcing in ice sheet development and its effect on the global climate system.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

摘要（非技术）海平面上升是一个具有全球重要性的问题，它正日益影响着数千万居住在沿海地区的美国人。全球变暖导致全球山区冰川融化，这是海平面上升和沿海洪灾增加的主要原因。然而，世界上最大的陆基冰盖位于极地地区，它们在持续变暖下的反应很难预测。这种不确定性的一个原因是缺乏对变暖条件下冰的行为和融化的观察，因为这是一个相对较新的全球气候状态，到目前为止只持续了几代人。研究人员将利用埋藏在南极洲附近海底沙层和泥层中的地质档案，调查过去温暖条件下南极洲冰层的生长情况。通过剥离海底下的冰层，调查人员可以阅读过去影响冰盖的事件的历史书。南极大陆位于南极，承载着世界上最大的冰块。研究人员的发现将大大提高科学家对冰盖对全球变暖的反应及其对海平面上升的影响的理解。摘要（技术）陆地冰的融化正在提高全球海平面，目前极地冰盖的贡献很小。然而，极地冰盖在未来气候变化中的作用是全球海平面上升预测中最关键的不确定因素之一。由于目前地球正在经历温室效应的极端上升，最近对极地气候学的测量很少涉及海洋和大气温室效应对冰盖的各自作用。关于南极西部冰盖演变的数据尤其稀少。为了解决数据缺口，研究人员将通过37至33 Ma的最后一次温室到冰窖气候转变来重建南极冰生长的时间和空间分布。他们将收集来自高纬度古档案的岩心样本的沉积学和地球化学数据，以追踪化学风化系统的关闭，冰川侵蚀的开始，冰漂流和海冰的发展，因为东、西南极冰盖在威德尔海地区合并。他们的发现将使人们深刻地认识到温室效应在冰盖形成中的作用及其对全球气候系统的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Eolian sand dispersal via sea ice on the Antarctic continental margin during Pliocene deglaciation

上新世冰川消退期间南极大陆边缘的风沙通过海冰扩散

• 发表时间: 2020
• 期刊: American Geophysical Union
• 作者: Sandra Passchier, Melissa Hansen

IDENTIFICATION OF ICE-RAFTED DEBRIS IN THE WEDDELL SEA TO CHARACTERIZE GLACIATION AT THE EOCENE-OLIGOCENE TRANSITION

• DOI: 10.1130/abs/2020am-356711
• 发表时间: 2020
• 作者: J. Horowitz;S. Passchier

Impact of Eocene‐Oligocene Antarctic Glaciation on the Paleoceanography of the Weddell Sea

• DOI: 10.1029/2022pa004440
• 发表时间: 2022-12
• 期刊: Paleoceanography and Paleoclimatology
• 影响因子: 3.5
• 作者: Victoria Hojnacki;A. Lepp;Josie Horowitz Castaldo;Abbey States;Xiaona Li;S. Passchier

Eocene to Oligocene cooling and ice growth based on the geochemistry of interglacial mudstones from the East Antarctic continental shelf

• DOI: 10.1017/s0954102023000159
• 发表时间: 2023-08
• 期刊: Antarctic Science
• 影响因子: 1.6
• 作者: J. Light;S. Passchier

Late Eocene Record of Hydrology and Temperature From Prydz Bay, East Antarctica

• DOI: 10.1029/2020pa004204
• 发表时间: 2021-04
• 期刊: Paleoceanography and Paleoclimatology
• 影响因子: 3.5
• 作者: E. J. Tibbett;H. Scher;S. Warny;J. Tierney;S. Passchier;S. Feakins