Collaborative Research: Characterizing Arctic Climate Extremes from the Pliocene to the Present: the view from Lake El'gygytgyn, western Beringia

在格陵兰冰芯覆盖的时间段之外，高北极地区对过去气候事件的区域反应鲜为人知。然而，在2009年春天，从El'gygytgyn湖成功恢复了360万年的沉积物记录，这是一个直径12公里的陨石坑湖，位于俄罗斯东北部楚科奇市北极圈以北100公里处。这笔拨款将继续研究湖心的古气候记录。对沉积记录的分析将大大延长已知的气候史。该小组将把数据分析与气候模型结合起来，以检验关于北极高纬度气候与其他地区气候之间关系的四个假设。首先，目前还没有北极陆地记录足够详细地覆盖了布伦赫斯中期的转变，因此无法确定在南极最初几个100天周期中观测到的较冷的间冰期是否也出现在北极。第二，40ky的振幅？早更新世期间北极陆地冰川/间冰期旋回的持续时间尚不清楚。第三，上新世晚期北极陆地温度也是未知的，这是一个大气二氧化碳分压升高的时期。第四，该小组将调查海洋同位素阶段2期间北极温度对冷却的响应。这些结果将有助于确定北极对大气二氧化碳水平的敏感性。这项资助将为科学界提供有关100天冰期旋回、40天冰期旋回以及北半球冰期开始之前北极气候变化幅度的信息。这些数据将允许与EPICA冰芯、亚洲长黄土、洞穴和湖泊记录、可比较的海洋记录和全球气候[计算机]模型进行直接比较。公众和决策者都对气候变化问题感到困惑。这项工作应该有助于澄清北极气候自然变化的背景，这样就可以在背景中看到现代的变化。四名博士生和一名博士后将获得科学和指导支持。此外，该团队将通过每年夏天将五名马萨诸塞州西部的教师带到马萨诸塞大学来培训STEM教师，为期两周，以获得动手实验室和实地经验，并共同开发解决马萨诸塞州教育部科学标准核心要素的课程。由于湖泊和池塘在美国部分地区很常见，教师培训的一部分将集中在湖泊/池塘沉积物方面，他们可以在他们的社区中记录环境和气候变化。这将与2009年在El'gygytgyn湖担任PolarTREC老师的中学地球科学老师合作完成。

The regional response of the high Arctic to past climate events is little known beyond the time period covered by the Greenland ice cores. However, in Spring 2009, a 3.6 million year long sediment record was successfully recovered from Lake El'gygytgyn, a 12km diameter meteor crater lake located 100km north of the Arctic Circle in Chukotka, NE Russia. This grant will continue studies of the paleoclimate record from the lake cores. Analysis of the sedimentary record will greatly extend the known climate history. The team will integrate data analysis with climate modeling to test four hypotheses regarding the relationship between high Arctic climate and climate of other regions. First, no terrestrial Arctic record yet covers the mid-Brunhes transition in sufficient detail to determine whether the cooler interglacial periods observed in the first several 100ky cycles in the Antarctic are also found in the Arctic. Second, the amplitude of 40ky?duration glacial/interglacial cycles in the terrestrial Arctic during early Pleistocene is not known. Third, terrestrial Arctic temperatures during the Late Pliocene, a period of elevated atmospheric pCO2, are also unknown. Fourth, the team will investigate Arctic temperature response to cooling during Marine Isotope Stage 2. These results will help determine the sensitivity of the Arctic to atmospheric CO2 levels. This grant will provide the scientific community with information about the magnitude of climate changes in the Arctic during the 100ky glacial cycles, the 40ky glacial cycles, and from prior to the initiation of Northern hemisphere glaciations. These data will allow direct comparison to the EPICA ice cores, long Asian loess, speleothem, and lake records, and comparable marine records and Global Climate [computer] Models. Both the public and policy makers remain confused about issues relating to climate change. This work should help clarify the background of natural variations in Arctic climate, so that the modern changes can be seen in context.Four PhD students and one post-doctoral fellow will receive science and mentoring support. In addition, the team will train STEM teachers by bringing five western Massachusetts teachers per summer to UMass for two weeks to gain hands-on laboratory and field experience and jointly develop curricula that address core elements of the Massachusetts Department of Education science standards. Because lakes and ponds are common across parts of the US, a portion of the teacher training will focus on lake/pond sediments with regard to the environmental and climate change they can document in their communities. This will be accomplished in collaboration with the middle school Earth science teacher who was at Lake El'gygytgyn in 2009 as the PolarTREC teacher.