Collaborative research: Exploring the role of oceanic and atmospheric forcing on Arctic marine climate from newly developed annual shell based records in coastal Norway

合作研究：从挪威沿海新开发的年度贝壳记录中探索海洋和大气强迫对北极海洋气候的作用

• 批准号: 1417636
• 负责人: Michael Retelle
• 金额: $ 33.72万
• 依托单位: Bates College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417636&HistoricalAwards=false
• 关键词: Collaborative; research; Exploring; role; oceanic

Oceanographers and paleoclimatologists use various proxies to study the past history of ocean temperature and salinity. Many of these are recorded in the marine sediments, but sedimentation rates are so small that the time series that can be estimated from them only resolve changes that occur on decadal time scales or longer. When clams and other bivalves grow, they incorporate, in their shells, geochemical signatures from the water in which they live. They also lay down growth rings, like tree rings, in their shells. By studying the chemistry of adjacent rings in long-lived clam shells the principal investigators (PIs) of this project expect to be able to reconstruct the annual temperature and salinity variations of near surface waters in a region offshore of northern Norway. They will focus their efforts on the Medieval Warm Period (1000 AD to 1200 AD), the Little Ice Age (1200 AD to 1850 AD), and the modern era (1850 AD until the present). The resultant histories of temperature and salinity variation will be useful for understanding how the ocean conditions changed during these known periods of climate variation and for validating or constraining climate models.The PIs? immediate goal is to reconstruct annual hydrographic variability during key climate intervals within the last millennium along the strategically located Arctic islands of Ingoy and Rolvsoy. They will hindcast changes in annual sea surface temperature (SST) and sea surface salinity (SSS). They will also establish the baseline variability in the marine radiocarbon reservoir effect. The modern near-surface oceanography along the islands is influenced by the physical properties of the Norwegian Coastal Current, while the relatively deep hydrographic conditions predominately depend on Atlantic inflow. Pilot data from the study site demonstrate a strong link between shell-based records and regional SST/SSS conditions. Hence, Ingoy and Rolvsoy seem situated in an ideal location to study marine climate change during the late Holocene. Hypotheses and objectives have been developed to test the relative influence of dominant climate modes on the regional oceanography near northern Norway during the last millennium.Objective 1: Develop near-surface annual shell-based records (master shell chronology and isotopes) to reconstruct regional hydrographic variability (SST and SSS) along the northernmost coast of Norway during intervals of the Medieval Climate Anomaly, the Little Ice Age, and for Modern Climate.Objective 2: Develop relatively deep-water (200 m) annual shell-based records (master shell chronology and isotopes) for the last 100 years to characterize the role of the North Atlantic Current on hydrography at the site.Objective 3: Establish a decadal record of the surface marine radiocarbon reservoir effect since AD 1600 to estimate changes in source water contributions at Ingoy.Objective 4: Estimate the relative influence of the winter North Atlantic Oscillation, the surface Atlantic Meridional Overturning Circulation, and the Atlantic Multidecadal Oscillation on regional hydrography (at Ingoy) and shell-based records.An international partnership for studying Arctic marine climate change will be developed with colleagues from the Akvaplan-niva (Norway), Iowa State University (ISU) and Bates College (Maine). Outreach, public engagement, and dissemination of the results will be accomplished through engagement of two K-12 teachers in the field work, through classroom interactions with K-12 students, through a K-12 teacher workshop, through citizen-based science (via interactions with native Norwegians at Ingoy), and via a photo-journalist who will join the PIs for one field season. At least one female PhD student and approximately five undergraduate students will be supported by and involved with the project. The PIs will use data and ideas developed in this project for several courses at ISU and Bates College relating to climate change, paleoclimate and oceanography. PI Wanamaker will facilitate a public lecture series on climate change at the Ames Public library and continue to act as co-chair of Edwards Elementary Science Night, which has impacted 1,000 students and community members since 2012.

海洋学家和古气候学家使用各种代理来研究海洋温度和盐度的过去历史。 其中许多记录在海洋沉积物中，但是沉积速率是如此之小，以至于可以从它们中估算的时间序列只能解决在十年时间或更长的时间范围内发生的变化。 当蛤lam和其他双壳类生长时，它们将其居住水的地球化学签名纳入了壳中。 他们还在贝壳中铺设生长环，例如树环。 通过研究长寿命蛤shell中相邻环的化学反应，该项目的主要研究人员（PIS）希望能够重建挪威北部地区近海地区近地面水的年温度和盐度变化。 他们将把努力集中在中世纪的温暖时期（公元1000年至公元1200年），小冰河时代（公元1200年至1850年）和现代时代（直到现在为止）。 最终的温度和盐度变化历史将有助于理解在这些已知气候变化期间以及验证或约束气候模型的海洋条件如何变化。直接的目标是在上一千年的关键气候间隔内重建年度水文变异性，沿着战略性的北极岛Ingoy和Rolvsoy。它们将在年度海面温度（SST）和海面盐度（SSS）中变化。他们还将建立海洋放射性碳储存效应的基线变异性。沿岛屿的现代近地面海洋学受到挪威沿海电流的物理特性的影响，而相对深层的水文条件主要依赖于大西洋流入。来自研究站点的试点数据表明，基于壳的记录与区域SST/SSS条件之间存在牢固的联系。因此，在全新世晚期，Ingoy和Rolvsoy似乎位于研究海洋气候变化的理想位置。已经开发了假设和目标，以测试上一个千年期间挪威北部北部北部地区海洋学的相对影响。目标1：发展近地面年度基于壳的记录（主壳的壳壳和同位素）对重建区域水文变异性（SST和SSS）在挪威北部的界限范围内，并在MEDIEV INTECTALS INTECTAL MERDAIM CLICTANS INTECTAL CLINDON和MERTAIM CLINGES沿着MEDIEV MERTAIM CLITIST沿着MEDIEV MERTAIM CLICTION INTEROM INTECTANCE进行了冰箱，并且气候2：在过去的100年中发展相对深水（200 m）年度基于外壳的记录（主壳的年代和同位素），以表征北大西洋电流在网站上的水文图中的作用。目标3：建立decadal记录的衰老记录，表面上的海洋放射性碳储备效应，自AD量的相对范围内的介绍量的越野范围内的介绍量。振荡，地面大西洋子午倾覆的循环以及大西洋多年气流图（INGOY）和基于壳牌的记录和基于壳牌的记录。外展，公众参与和对结果的传播将通过两名K-12老师在实地工作中的参与，通过与K-12学生的课堂互动，通过K-12教师研讨会，通过基于公民的科学（通过与Ingoy的本地人的互动）以及通过Photo-Journalist与PIS一起参加PIS进行一次现场赛季的互动。该项目将至少有一名女博士生和大约五名本科生的支持和参与。 PI将在此项目中使用与气候变化，古气候和海洋学有关的ISU和贝茨学院的多个课程开发的数据和想法。 Pi Wanamaker将促进AMES公共图书馆的公开演讲系列有关气候变化的公开演讲，并继续担任Edwards Electrary Science Night的联席主席，该夜影响自2012年以来影响了1,000名学生和社区成员。