Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements

合作研究：使用化学和微粒测量的南极冰芯年代学和气候记录

• 批准号: 1443397
• 负责人: Karl Kreutz
• 金额: $ 38.93万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443397&HistoricalAwards=false
• 关键词: Collaborative; Research; South; Pole; Ice

This collaborative project explores the signatures and causes of natural climate change in the region surrounding Antarctica over the last 40,000 years as the Earth transitioned from an ice age into the modern warm period. The researchers will investigate how the wind belts that surround Antarctica changed in their strength and position through time, and document explosive volcanic eruptions and CO2 cycling in the Southern Ocean as potential climate forcing mechanisms over this interval. Understanding how and why the climate varied naturally in the past is critical for improving understanding of modern climate change and projections of future climate under higher levels of atmospheric CO2. The investigators plan to conduct a suite of chemical measurements along the 1500m length of the South Pole Ice Core, including major ion and trace element concentrations, and microparticle (dust) concentrations and size distributions. These measurements will (1) extend the South Pole record of explosive volcanic eruptions to 40,000 years using sulfate and particle data; (2) establish the relative timing of climate changes in dust source regions of Patagonia, New Zealand, and Australia using dust flux data; (3) investigate changes in the strength and position of the westerly wind belt using dust size distribution data; and (4) quantify the flux of bioavailable trace metals deposited as dust to the Southern Ocean over time. These chemistry records will also be critical for creating the timescale that will be used by all researchers studying records from the South Pole core. The project will support four graduate students and several undergraduate students across three different institutions, and become a focus of the investigators' efforts to disseminate outcomes of climate change science to the broader community.

该合作项目探讨了过去 4 万年来，随着地球从冰河时代过渡到现代温暖期，南极洲周边地区自然气候变化的特征和原因。研究人员将研究南极洲周围的风带的强度和位置如何随时间变化，并记录南大洋的火山喷发和二氧化碳循环，作为这一时期潜在的气候强迫机制。了解过去气候如何以及为何自然变化对于增进对现代气候变化的理解以及在大气二氧化碳含量较高的情况下预测未来气候至关重要。研究人员计划沿南极冰芯 1500m 长度进行一系列化学测量，包括主要离子和微量元素浓度，以及微粒（灰尘）浓度和尺寸分布。这些测量将 (1) 使用硫酸盐和颗粒数据将南极火山喷发的记录延长至 40,000 年； (2) 利用沙尘通量数据确定巴塔哥尼亚、新西兰和澳大利亚沙尘源区气候变化的相对时间； (3) 利用粉尘粒径分布数据研究西风带强度和位置的变化； (4) 量化随着时间的推移以灰尘形式沉积到南大洋的生物可利用微量金属的通量。 这些化学记录对于创建所有研究南极核心记录的研究人员将使用的时间尺度也至关重要。该项目将为三个不同机构的四名研究生和几名本科生提供支持，并成为研究人员向更广泛的社区传播气候变化科学成果的努力的焦点。