Collaborative Research: The Timing and Spatial Expression of the Bipolar Seesaw in Antarctica from Synchronized Ice Cores

合作研究：从同步冰芯观察南极洲双极跷跷板的时间和空间表达

• 批准号: 1643355
• 负责人: Eric Steig
• 金额: $ 9.9万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2021-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1643355&HistoricalAwards=false
• 关键词: Collaborative; Research; Timing; Spatial; Expression

Buizert/1643394This award supports a project to use ice cores to study teleconnections between the northern hemisphere, tropics, and Antarctica during very abrupt climate events that occurred during the last ice age (from 70,000 to 11,000 years ago). The observations can be used to test scientific theories about the role of the westerly winds on atmospheric carbon dioxide. In a warming world, snow fall in Antarctica is expected to increase, which can reduce the Antarctic contribution to sea level rise, all else being equal. The study will investigate how snow fall changed in the past in response to changes in temperature and atmospheric circulation, which can help improve projections of future sea level rise. Antarctica is important for the future evolution of our planet in several ways; it has the largest inventory of land-based ice, equivalent to about 58 m of global sea level and currently contributes about 0.3 mm per year to global sea level rise, which is expected to increase in the future due to global warming. The oceans surrounding Antarctica help regulate the uptake of human-produced carbon dioxide. Shifts in the position and strength of the southern hemisphere westerly winds could change the amount of carbon dioxide that is absorbed by the ocean, which will influence the rate of global warming. The climate and winds near and over Antarctica are linked to the rest of our planet via so-called climatic teleconnections. This means that climate changes in remote places can influence the climate of Antarctica. Understanding how these climatic teleconnections work in both the ocean and atmosphere is an important goal of climate research. The funds will further contribute towards training of a postdoctoral researcher and an early-career researcher; outreach to public schools; and the communication of research findings to the general public via the media, local events, and a series of Wikipedia articles. The project will help to fully characterize the timing and spatial pattern of millennial-scale Antarctic climate change during the deglaciation and Dansgaard-Oeschger (DO) cycles using multiple synchronized Antarctic ice cores. The phasing of Antarctic climate change relative to Greenland DO events can distinguish between fast atmospheric teleconnections on sub-decadal timescales, and slow oceanic ones on centennial time scales. Preliminary work suggests that the spatial pattern of Antarctic change can fingerprint specific changes to the atmospheric circulation; in particular, the proposed work will clarify past movements of the Southern Hemisphere westerly winds during the DO cycle, which have been hypothesized. The project will help resolve a discrepancy between two previous seminal studies on the precise timing of interhemispheric coupling between ice cores in both hemispheres. The study will further provide state-of-the-art, internally-consistent ice core chronologies for all US Antarctic ice cores, as well as stratigraphic ties that can be used to integrate them into a next-generation Antarctic-wide ice core chronological framework. Combined with ice-flow modeling, these chronologies will be used for a continent-wide study of the relationship between ice sheet accumulation and temperature during the last deglaciation.

Buizert/1643394该奖项支持一个利用冰芯研究北方、热带和南极洲在上一个冰河时代（7万至11,000年前）发生的非常突然的气候事件期间的遥相关的项目。这些观测结果可以用来检验西风对大气二氧化碳作用的科学理论。在一个变暖的世界里，南极洲的降雪量预计会增加，这可以减少南极洲对海平面上升的贡献，所有其他因素都是平等的。这项研究将调查过去降雪量如何随着温度和大气环流的变化而变化，这有助于改善对未来海平面上升的预测。 南极洲在几个方面对我们星球的未来演变很重要;它拥有最大的陆基冰存量，相当于全球海平面的约58米，目前每年使全球海平面上升约0.3毫米，由于全球变暖，预计未来还会增加。南极洲周围的海洋有助于调节人类产生的二氧化碳的吸收。南半球西风位置和强度的变化可能会改变海洋吸收的二氧化碳量，这将影响全球变暖的速度。南极洲附近和上空的气候和风通过所谓的气候遥相关与地球其他地区联系在一起。这意味着偏远地区的气候变化可能会影响南极洲的气候。了解这些气候遥相关如何在海洋和大气中起作用是气候研究的一个重要目标。 这些资金将进一步促进博士后研究人员和早期职业研究人员的培训;与公立学校的联系;以及通过媒体，当地活动和一系列维基百科文章向公众传播研究成果。该项目将利用多个同步的南极冰芯，帮助充分描述冰川消退和Dansgaard-Oeschger（DO）周期期间千年尺度南极气候变化的时间和空间模式。南极气候变化相对于格陵兰溶解氧事件的阶段性变化可以区分近十年时间尺度上的快速大气遥相关和百年时间尺度上的慢速海洋遥相关。初步工作表明，南极变化的空间格局可以识别大气环流的具体变化;特别是，拟议的工作将澄清过去的运动，南半球西风在DO周期，这是假设。该项目将有助于解决之前两项关于两个半球冰芯之间半球间耦合精确时间的开创性研究之间的差异。该研究将进一步为所有美国南极冰芯提供最先进的，内部一致的冰芯年表，以及可用于将其整合到下一代舌形冰芯年表框架中的地层关系。结合冰流模型，这些年表将被用于在整个大陆范围内研究冰盖积累和温度之间的关系，在最后一次冰川消退。

项目成果

A 2700-year annual timescale and accumulation history for an ice core from Roosevelt Island, West Antarctica

• DOI: 10.5194/cp-15-751-2019
• 发表时间: 2017-08
• 期刊: Climate of the Past
• 影响因子: 4.3
• 作者: Paul Kjaer;Helle A. Fudge;Tyler J. Lee;James E. Riis;M. Winstrup;P. Vallelonga;H. Kjær;T. Fudge;James E. Lee;Marie H. Riis;R. Edwards;N. Bertler;T. Blunier;E. Brook;C. Buizert;G. Ciobanu;H. Conway;D. Dahl-Jensen;Aja Ellis;B. D. Emanuelsson;R. Hindmarsh;E. Keller;A. Kurbatov;P. Mayewski;P. Neff;Rebecca L. Pyne;M. Simonsen;A. Svensson;Andrea Tuohy;E. Waddington;Sarah D. Wheatley

Regional Antarctic snow accumulation over the past 1000 years

• DOI: 10.5194/cp-13-1491-2017
• 发表时间: 2017-11-10
• 期刊: CLIMATE OF THE PAST
• 影响因子: 4.3
• 作者: Thomas, Elizabeth R.;van Wessem, J. Melchior;Ekaykin, Alexey A.
• 通讯作者: Ekaykin, Alexey A.

Abrupt ice-age shifts in southern westerly winds and Antarctic climate forced from the north

• DOI: 10.1038/s41586-018-0727-5
• 发表时间: 2018-11-29
• 期刊: NATURE
• 影响因子: 64.8
• 作者: Buizert, Christo;Sigl, Michael;Steig, Eric J.
• 通讯作者: Steig, Eric J.