Establishing the Onset and History of Perennial Sea Ice in the Arctic

2004年IODP北极取心探险(ACEX)期间从Lomonosov海脊发现的岩心材料将通过应用氧化铁指纹技术，用于重建北冰洋海冰的历史。这种方法使研究人员能够追踪碎屑沉积物的来源到环北冰洋的特定区域。假设季节性冰和常年冰从不同的位置和距离向洛蒙诺索夫海脊输送沉积物，研究人员将对可追溯到15-17 Ma的连续岩心剖面和覆盖~44 Ma至古新世的其他岩心剖面进行详尽的分析，以推断岩芯中所代表的常年和季节性冰的模式。这一结果将不仅对北极海冰历史和古气候提供限制，而且还对古环流模式提供限制。这些信息对于更准确地重建古气候情景和更好地预测未来气候变化至关重要。更广泛的影响包括这项研究将对北极气候历史和对独特的IODP ACEX核心的分析做出的关键贡献，与加拿大和欧洲研究人员的合作，以及对本科生和研究生的培训。

Core material recovered from the Lomonosov Ridge during the 2004 IODP Arctic Coring Expedition (ACEX) will be used to reconstruct the history of sea ice in the Arctic Ocean through application of the iron oxide fingerprinting technique. This method permits researchers to trace the origin of detrital sediments to specific regions of the circum-Arctic Ocean. Hypothesizing that seasonal ice and perennial ice deliver sediments to the Lomonosov Ridge from different locations and distances, the researchers will conduct exhaustive analyses of continuous core sections dating back to 15-17 Ma and other core sections that cover the period from ~44 Ma back to Paleocene time to infer the patterns of perennial and seasonal ice represented in the cores. The results will provide constraints not only on Arctic sea ice history and paleoclimate, but also on paleocirculation patterns. Such information is critical for more accurate reconstruction of paleoclimate scenarios and better prediction of future climate change. Broader impacts include the critical contributions this research will make to Arctic climate history and the analysis of the unique IODP ACEX cores, collaboration with Canadian and European researchers, and training of undergraduate and graduate students.