Interpretation of the High Resolution, Multivariate Mt. Logan (Yukon Territory) Ice Core - A Record of North Pacific Climate and Atmospheric Chemistry

高分辨率、多元洛根山（育空地区）冰芯的解释 - 北太平洋气候和大气化学的记录

• 批准号: 0612400
• 负责人: Paul Mayewski
• 金额: $ 12.97万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0612400&HistoricalAwards=false
• 关键词: Interpretation; Resolution; Multivariate; Mt.; Logan

ABSTRACTMayewskiOPP-0612400The recently developed Mt. Logan ice core glaciochemical dataset provides an unprecedented opportunity to understand Holocene climate change and the sources and fluxes of natural and anthropogenic chemicals in the North Pacific atmosphere. The 185 m-long ice core has been sampled at very high resolution using a refined and updated continuous ice core melter system, and analyzed for over 40 chemical species, including major ions, trace elements, rare earth elements, and stable isotopes. Subseasonal samples spanning the top ~500 years allow for annual layer counting, followed by ice flow modeling for the remainder of the timescale spanning the Holocene and portions of the late glacial period. Its continuous and high-resolution samples, breadth of co-registered chemical measurements, time span and location in the North Pacific free troposphere make the Mt. Logan glaciochemical dataset a new benchmark in ice core analyses with the potential for understanding paleoclimate variability and atmospheric chemistry far beyond the boundaries of the soon to be completed initial project. Interpretation of the new Mt. Logan record suggests that anthropogenic pollutants from Asia.have contaminated the North Pacific free troposphere since the early 1970s. Mt. Logan dust and sea-salt concentrations show statistically significant correlations to atmospheric pressure centers over their Asian desert and Pacific Ocean source regions, respectively. Funds are requested for a graduate student, and subsequent post-doctoral researcher, to continue interpretation of this unique record, and produce additional chemical time series from existing samples and archived core. This graduate student was responsible for expanding the University of Maine capabilities continuous ice melter system, producing the Mt. Logan glaciochemical record, and interpreting the dataset, and consequently has pre-existing, extensive knowledge of the dataset and the study area.Intellectual Merit of the Proposed Activity: This research will build upon previousinterpretations of the Mt. Logan record, while adding specific new time series to clarify the sources of Asian anthropogenic metals and natural dust. It will directly contribute to the understanding of:1) Anthropogenic and natural aerosol emissions and their sources, particularly from Asia,2) Millennial scale Northern Hemisphere Holocene climate variability and forcing mechanisms,3) Annual to decadal scale North Pacific Holocene climate variability and forcing mechanisms,4) Recent climate change in the North Pacific that is climatologically linked to Earth's, thus far, region of greatest response to greenhouse gas warming, the Arctic.Using multivariate statistics and time series analyses, the timing, intensity and forcing mechanisms of North Pacific annual to millennial climate fluctuations will be investigated by comparing the Mt. Logan summit record to regional proxy records from ice cores at lower elevations, tree rings, lake and marine sediment cores, glaciers, and existing climate forcing records. Links between northern hemisphere and tropical climate patterns and the nature of global Holocene climate shifts will be investigated by comparing the Mt. Logan record to ice core and paleoclimate proxy records from globally distributed locations.Broader Impacts: Interpretations from this record will contribute to understand the potential for future climate changes over North America, the Pacific and Asia, and the impact of land-use changes and industrialization by Asian countries on the North American atmosphere. All data produced by this project will be provided to WDC-A for Glaciology and WDC for paleoclimatology.

最近开发的Mt. Logan冰芯冰川化学数据集为了解全新世气候变化以及北太平洋大气中自然和人为化学物质的来源和通量提供了前所未有的机会。185米长的冰芯已被采样在非常高的分辨率使用一个完善和更新的连续冰芯熔化系统，并分析了40多个化学物种，包括主要离子，微量元素，稀土元素和稳定同位素。跨越顶部~500年的亚季节样本允许每年的层计数，其次是跨越全新世和部分晚冰期的时间尺度的剩余部分的冰流建模。其连续和高分辨率的样本，共同注册的化学测量，时间跨度和北太平洋自由对流层的位置的广度，使山。洛根冰川化学数据集是冰芯分析的新基准，有可能了解古气候变化和大气化学，远远超出即将完成的初始项目的界限。 新的Mt的解释。洛根记录表明，自20世纪70年代初以来，来自亚洲的人为污染物已经污染了北太平洋自由对流层。 山洛根灰尘和海盐浓度显示统计上显着的相关性，大气压力中心在亚洲沙漠和太平洋源区，分别。要求为一名研究生和随后的博士后研究人员提供资金，以继续解释这一独特的记录，并从现有样品和存档的岩心中产生更多的化学时间序列。这名研究生负责扩大缅因州大学的能力连续融冰系统，生产山。洛根冰川化学记录，并解释数据集，因此有预先存在的，广泛的知识的数据集和研究领域。Logan记录，同时增加了具体的新的时间序列，以澄清亚洲人为金属和自然尘埃的来源。它将直接有助于理解：1）人为和自然气溶胶排放及其来源，特别是来自亚洲，2）千年尺度的北方半球全新世气候变率和强迫机制，3）年度至十年尺度的北太平洋全新世气候变率和强迫机制，4）在气候学上与地球的，迄今为止，对温室气体变暖的最大响应地区，北极最近的气候变化。洛根峰会记录，以区域代理记录从冰芯在低海拔，树木年轮，湖泊和海洋沉积物芯，冰川，和现有的气候强迫记录。将通过比较Mt..研究北方和热带气候模式之间的联系以及全球全新世气候变化的性质。更广泛的影响：对这一记录的解释将有助于了解北美、太平洋和亚洲未来气候变化的潜力，以及亚洲国家土地利用变化和工业化对北美大气的影响。该项目产生的所有数据将提供给WDC-A用于冰川学和WDC用于古气候学。