Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine and Quaternary Geosciences

该奖项支持一艘研究邮轮在南极半岛前拉森B冰架下方和周围地区进行地质研究。2002年冰架的解体，加上该地区独特的海洋地质，使人们有可能了解导致冰架崩塌的条件。冰架是气候变化的风向标，反映了海洋和大气条件，也阻碍了极地关键地区的冰川流动。它们的坍塌导致冰川激增，并可能导致全球海平面迅速上升。该项目描述了拉森冰架的历史和导致其崩溃的条件，确定了：1)12.5万年前伊米亚间冰期气候变暖和海平面升高期间拉森B冰架的大小；2)末次盛冰期期间南极半岛冰盖的形状及其随后的消退；3)拉森B冰架在全新世期间保持稳定的原因，在此期间其他冰架来来去去；4)对冰架边缘动力学的控制，特别是表面融化和海洋过程的作用，以及5)大冰架解体后，生物和岩石成因的沉积物通量的变化。更广泛的影响包括通过研究项目和讲习班开展研究生和本科教育；通过电视纪录片和网站向公众宣传；与比利时、西班牙、阿根廷、加拿大、德国和英国的科学家开展国际合作。这部作品还具有重要的社会意义。提高我们对冰架在全球变暖中的行为的理解，将改进海平面上升的模型。该项目由美国国家科学基金会的国际极地年(IPY)研究重点领域“了解极地地区的环境变化”支持。

AbstractThis award supports a research cruise to perform geologic studies in the area under and surrounding the former Larsen B ice shelf, on the Antarctic Peninsula. The ice shelf's disintegration in 2002 coupled with the unique marine geology of the area make it possible to understand the conditions leading to ice shelf collapse. Bellwethers of climate change that reflect both oceanographic and atmospheric conditions, ice shelves also hold back glacial flow in key areas of the polar regions. Their collapse results in glacial surging and could cause rapid rise in global sea levels. This project characterizes the Larsen ice shelf's history and conditions leading to its collapse by determining: 1) the size of the Larsen B during warmer climates and higher sea levels back to the Eemian interglacial, 125,000 years ago; 2) the configuration of the Antarctic Peninsula ice sheet during the LGM and its subsequent retreat; 3) the causes of the Larsen B's stability through the Holocene, during which other shelves have come and gone; 4) the controls on the dynamics of ice shelf margins, especially the roles of surface melting and oceanic processes, and 5) the changes in sediment flux, both biogenic and lithogenic, after large ice shelf breakup. The broader impacts include graduate and undergraduate education through research projects and workshops; outreach to the general public through a television documentary and websites, and international collaboration with scientists from Belgium, Spain, Argentina, Canada, Germany and the UK. The work also has important societal relevance. Improving our understanding of how ice shelves behave in a warming world will improve models of sea level rise. The project is supported under NSF's International Polar Year (IPY) research emphasis area on "Understanding Environmental Change in Polar Regions".