Oceanographic and Biological Implications of Arctic Sea-Ice Change: Evidence from Quaternary Benthic Foraminifers

该项目将通过使用新发现的、连续的北极微动物记录来描述北极西部从季节性无冰到常年被冰覆盖和冰川影响的海洋环境的转变，从而深入了解海冰覆盖的历史和深海动物群的相关演变。本研究的重点将集中在：(1)详细研究早更新世有孔虫、介形类和相关沉积代用物的分布，这一时期主要是季节性海冰和少量冰川的时期；(2)在至少半球尺度的广泛地理和古气候背景下，将这些记录与北大西洋的相关IODP数据进行比较；(3)分析了北冰洋西部地理分布的岩心在主要气候转变和较年轻地层暖期的有孔虫和介形类的分布及其海冰覆盖情况。最近观测到的和正在进行的海冰分布变化预计将对北极特有物种产生重大影响。在这个项目中开发的数据将对试图了解北极系统过去变化和预测未来变化的建模者很有用。

This project will provide insights into the history of sea-ice cover and related evolution of deep-sea fauna by using newly discovered, continuous Arctic microfaunal records characterizing a transition from seasonally ice-free to perennially ice-covered and glacially-affected oceanic environments in the western Arctic. The major thrusts of the proposal will focus on (1) investigating, in detail, foraminiferal distribution along with ostracodes and related sedimentary proxies in the Early Pleistocene, the time of mostly seasonal sea ice and little glacial inputs; (2) comparing these records to correlative IODP data from the North Atlantic for a broad geographic and paleoclimatic context of at least hemispheric scale; and (3) analyzing the distribution of foraminifers and ostracodes and, by proxy, sea-ice cover during the major climatic transitions and warm intervals in the younger stratigraphy in geographically distributed cores from the western Arctic Ocean.The recently observed and ongoing changes in sea ice distribution are expected to have significant impact on endemic Arctic species. The data developed during this project will be useful to modelers trying to understand past changes in the Arctic system and predict future changes.