High-Resolution Constraints on the Magnitude and Timing of Climate Change in Iceland Over the Past 15 ka.

这是科罗拉多大学和冰岛大学的主要研究人员之间的合作建议。冰岛位于寒冷的极地气团和来自热带的相对温暖的气团之间，位于寒冷、相对新鲜的东格陵兰洋流和温暖、含盐的北大西洋暖流之间。大气或海洋环流的细微变化可能造成了陆地环境的强烈变化。因此，北大西洋全新世环流变率对冰岛的影响可能比大多数其他北大西洋大陆更强。自人类定居以来，冰岛一直有环境变化的历史记录，观测到的巨大变化证实了冰岛的气候敏感性。该项目的目标是通过现在的间冰期重建冰岛的大冰盖，并记录冰川消融期间发生的突变，以及陆地环境变化的幅度、时间和可能的周期性。首席研究员将试图回答两个具体问题：1)一些现存的大冰盖在全新世早期消失了吗？如果是，它们是什么时候重新生长的？ 2)在冰川消融期间，陆地和近岸的环境条件是什么？将从两个深的、高沉积速率的湖泊盆地中恢复连续岩心。之所以选择这些湖泊，是因为沉积物有望为过去1万至1.5万年的环境变化提供高分辨率、定量的证据。首席研究员将采用多代理方法，重点研究沉积物的物理特征、湖泊初级生产力变化、孢粉学和海洋微古生物学。这些数据将使他们能够确定冰岛的全新世环境变化是否存在自然循环，类似于邻近海洋和格陵兰冰盖的报告。

Miller0138010This is a collaborative proposal among Principal Investigators at the Universities of Colorado and Iceland. Iceland is situated at the boundary between cold, polar air masses and relatively warm air masses of tropical origin and between the cold, relatively fresh East Greenland Current and the warm, salty North Atlantic Drift. Subtle shifts in either atmospheric or oceanic circulation may have produced strong changes in the terrestrial environment. Therefore, the impact of North Atlantic Holocene circulation variability was likely to be stronger on Iceland than most other North Atlantic landmasses. There has been a historical record of environmental change on Iceland since its settlement and the large variations observed confirm Iceland's climate sensitivity. The goal of the project is to reconstruct Iceland's large ice caps through the present interglacial and document abrupt shifts that occurred during deglaciation, and the magnitude, timing and possible cyclicity of terrestrial environmental change. The Principal Investigators will attempt to answer two specific questions: 1) did some of the extant large ice caps disappear in the early Holocene, and if so, when did they regrow and 2) what were the terrestrial and near-shore environmental conditions during deglaciation? Continuous cores from two deep, high-sedimentation-rate lake basins will be recovered. These lakes were selected because the sediments are expected to provide high-resolution, quantitative evidence of environmental change over the past 10 to 15 thousand years. The Principal Investigators will undertake a multiproxy approach, with an emphasis on physical characteristics of the sediments, lacustrine primary productivity changes, palynology, and marine micropaleontology. These data should allow them to determine whether there is a natural cyclicity in Holocene environmental change on Iceland, similar to that reported from the adjacent oceans and the Greenland Ice Sheet.