Collaborative Research: Millennial Scale Arctic Climate Change for the last 3.6 My: Scientific Drilling at Lake El'gygytgyn, NE Russia

El'gygytgyn湖是西伯利亚东北部的一个撞击坑，其沉积记录已成为古气候研究的焦点，现在被国际大陆钻探计划（ICDP）认为是一个高度优先的世界级钻探目标。1998年和2003年从湖泊最深处（170 m）提取的沉积物岩心显示，湖泊的基本年龄为~ 250和近300 ka，并在千年时间尺度上再现了湖泊对东北亚气候变化的敏感性。这些岩心是迄今为止最古老的北极陆地岩心。这笔拨款将支持在2008年春季获得更深的岩心，直至基岩。这些岩心可能会提供距今3万多年前的北极气候记录。地震测量显示400米的沉积物覆盖在冲击角砾岩上。这笔拨款是美国与ICDP、加拿大、德国和俄罗斯政府一道，为一项多国努力做出的贡献，目的是找回这些核心并开展后续的科学研究。智力价值：目标是收集和解释北极陆地气候变化的最长时间连续记录，并将这些记录与低纬度海洋和陆地站点的记录进行比较，以更好地了解半球和全球气候变化。取心目标包括在靠近湖泊最深处的两个地点进行2个重复重叠的取心。在现在被冻结的冲积沉积物覆盖的湖泊沉积物上增加一个陆基核，将使人们更好地了解湖泊的沉积物供应。这些岩心将提供一个独特的北极记录，捕捉冰期/间冰期和千年尺度变化的机制和动力学，以便与来自海洋的其他长期记录进行比较。这将使科学家能够评估和模拟在41 ka和100 ka周期期间与日照强迫相关的系统遥相关和超前/滞后。这一记录将有助于了解在末次冰期旋回确定的快速变化事件是否为早期冰期的典型事件。这个核心将使我们能够通过从温暖的上新世中期到北半球第一次主要冰川开始的过渡来解决有关北极气候变化的演变和模式的问题。这些冰芯将提供亚洲东北北极对EPICA冰芯、长亚洲黄土和湖泊记录以及海洋记录所探测到的千年尺度突变和间冰期变暖的区域敏感性记录。更广泛的影响：这项工作将帮助我们了解北极气候自然变化的背景，以便在此背景下理解现代变化。由于这项工作将在国际极地年（IPY）期间进行，因此检索一个独特的北极核心将特别及时。研究成果的国际共享在我们的国家和个人之间建立了信任和相互尊重，也在莫斯科和俄罗斯偏远地区的政治团体和机构之间建立了信任和相互尊重。该提案将支持4所美国机构的研究生和本科生。大部分外联工作将以互联网为基础，结合最新的交互式3D地理信息系统和地形可视化技术，视频，以及与现场教育者的实时互动，所有这些都将该项目与IPY联系起来。

The sedimentary record of Lake El'gygytgyn, an impact crater in northeastern Siberia, has become a focus for paleoclimatic research and is now considered a high-priority, world-class target for drilling by the International Continental Drilling Program (ICDP). Sediment cores retrieved from the deepest part of the lake (170 m) in 1998 and 2003 revealed a basal age of ~ 250 and nearly 300 ka, and reproducibly demonstrated the sensitivity of the lake to climatic change across NE Asia at millennial timescales. These cores are the oldest terrestrial Arctic cores yet retrieved. This grant will support acquiring deeper cores in spring 2008 through to bedrock. The cores could potentially yield a record of Arctic climate dating back to over 3 My ago. Seismic measurements show 400 m of sediments overlying the impact breccias. This grant is the U.S. contribution to a multi-national effort to retrieve the cores and carry out subsequent scientific research, joining contributions from the ICDP, the Canadian, German and Russian governments.Intellectual merit: The goal is to collect and interpret the longest time-continuous record of climate change in the terrestrial Arctic and compare this record with those from lower latitude marine and terrestrial sites to better understand hemispheric and global climate change. Coring objectives include 2 replicate overlapping cores at 2 sites near the deepest part of the lake. One additional land-based core on lake sediments now overlain by frozen alluvial sediments will allow a better understanding of sediment supply to the lake. These cores will provide a unique Arctic record capturing the mechanisms and dynamics of glacial/interglacial and millennial-scale change for comparison with other long records from the oceans. This will allow scientists to evaluate and model systemic teleconnections and leads/lags relative to insolation forcing during periods of both 41 ka and 100 ka cycling. This record will provide insight as to whether rapid change events identified during the last glacial cycle are typical of earlier glacial periods. This core will allow us to address questions concerning the evolution and mode of Arctic climate change via the transition from the warm middle Pliocene to the onset of the first major Northern Hemisphere glaciation. The cores will provide a record of the regional sensitivity of the N E Asian Arctic to millennial-scale abrupt change and interglacial warmth detected in the timeframe of the EPICA ice cores, long Asian loess and lake records, and marine records.Broader impacts: This work will help us understand the background of natural variations in Arctic climate so that modern changes can be understood within that context. As this work will occur during the International Polar Year (IPY), the retrieval of a unique Arctic core will be especially timely. International sharing of research builds trust and mutual respect between our nations and individuals, but also between political bodies and institutions in Moscow and the more remote regions of Russia. This proposal will support graduate and undergraduates at 4 U.S. institutions. A large portion of the outreach efforts will be internet-based, incorporating the latest interactive 3D GIS and terrain visualization technology, video, and real-time interactions with educators in the field, all tying this project into the IPY.