Seafloor composition and Holocene sediment dynamics on the Canadian Arctic continental margins

对未来气候变化的预测表明，高纬度地区将比世界其他地区经历更大的环境波动。然而，为了从长期的历史角度看待这些环境变化，并为未来的北极气候模拟提供更全面的数据集，我们需要更好地了解加拿大北极海洋在晚第四纪的历史演变及其过去对气候突变的响应。在这种背景下，这个跨学科的提议，在北极海洋地质和古气候研究的前沿，旨在：1)获得对加拿大北极群岛或CAA中部海底沉积物的性质和起源的基本了解（即从加拿大波弗特海到兰开斯特海峡的区域）；2)评估全新世晚期气候变率（中世纪暖期、小冰期和近期变暖）对中亚带中部沉积物动态的影响；3)记录了巴芬（Penny）和埃尔斯米尔（Sydkap, Manson， Eugenie和Ekblaw）岛冰盖在全新世期间对海洋和气候条件变化的响应；4)重建了全新世气候边界条件变化与流入加冕湾和莫德皇后湾的北美北极河流的河流沉积制度的关系。这些雄心勃勃的目标将通过全面的源到汇分析来实现，包括粒度、定量矿物学、元素地球化学、恐龙囊组合和磁性参数，在一组独特的表面和高分辨率（0.08-0.30 cm/yr）的核心沉积物上，分布在CAA内一个大型准未勘探区域。该提案还旨在从北方研究补充计划中获得补充资金，以支付在北极收集沉积物样本所涉及的高昂费用，并在北极湾、剑桥湾和乌鲁卡托克的因纽特人社区开展推广活动。总的来说，拟议的前沿研究计划将提供一个非凡的多代理数据集，这将有助于我们目前对加拿大北极大陆边缘在十年、百年和千年时间尺度上不同气候条件下沉积过程的关键理解的根本性进步。从环境的角度来看，拟议的研究还将为几个因纽特人社区附近的沿海表层沉积物提供基线地球化学数据，这将有助于联邦政府机构（如加拿大环境与气候变化、加拿大土著事务和加拿大北部发展部）评估这些沿海地区的环境风险并制定污染物的监管水平。在海洋地质、古气候学和环境科学领域培养5名学士/2名硕士/3名博士研究生。

Projections of future climate change suggest that the high-latitude regions will experience greater environmental fluctuations than the rest of the world. However, to view these environmental changes from a long-term historical perspective and to provide a more comprehensive dataset for future Arctic climate simulations, we need to better understand the historical evolution of marine Arctic Canada through the late Quaternary and its past response to abrupt climate variations. In this context, this interdisciplinary proposal, at the forefront of Arctic marine geology and paleoclimate research, aims to: 1) acquire a fundamental understanding of the nature and origin of seafloor sediments in the central part of the Canadian Arctic Archipelago or CAA (i.e. area from the Canadian Beaufort Sea to the Lancaster Sound); 2) assess the impacts of late Holocene climate variability (Medieval Warm Period, Little Ice Age, and recent warming) on the sediment dynamics within the central part of the CAA; 3) document the response of marine-terminating outlet glaciers draining the Baffin (Penny) and Ellesmere (Sydkap, Manson, Eugenie and Ekblaw) Island icecaps to changing ocean and climatic conditions during the Holocene; and 4) reconstruct the fluvial sedimentary regimes of North American Arctic rivers draining into the Coronation and Queen Maud Gulfs in relationship to changing climatic boundary conditions during the Holocene. These ambitious goals will be addressed by using a holistic source-to-sink analysis, including grain size, quantitative mineralogy, elemental geochemistry, dinocyst assemblages and magnetic parameters, on a unique set of surface and high-resolution (0.08-0.30 cm/yr) core sediments distributed across a large quasi-unexplored area within the CAA. This proposal aims also to obtain supplementary funds from northern research supplements program to cover the high costs involved with sediment sample collection in the Arctic and to performed outreach activities in Inuit communities of Arctic Bay, Cambridge Bay, and Ulukhaktok. Overall, the proposed cutting-edge research program will provide a remarkable multiproxy dataset that will contribute to the fundamental advancement of our current critical understanding of sedimentation processes under varying climate conditions in the Canadian Arctic continental margins over decadal, centennial, and millennial timescales. From an environmental perspective, the proposed research will also provide baseline geochemical data for coastal surface sediments close to several Inuit communities, which will help federal government agencies (e.g., Environment and Climate Change Canada, Aboriginal Affairs and Northern Development Canada) with assessing environmental risk and setting regulatory levels of pollutants in these coastal areas. Finally, the proposed research program will contribute to the training of 5 BSc/2 MSc/3 PhD students in the fields of marine geology, paleoclimatology, and environmental sciences.