摘要
在全球变暖背景下,北极海冰覆盖面积持续减少,对全球的温盐环流、海洋生物化学过程和气候变化产生了深远的影响,研究北极古海冰的变化可以使我们对北极环境有全面的认识,更准确地预测其未来的变化规律。近十年来,一种新发展的海冰生物标志物IP25(Ice Proxy with 25 carbon atoms)被广泛用于北极及亚北极的海冰重建。IP25是北极冰藻产生的一种高度分化的单不饱和类异戊二烯(HBIs),能够稳定地保存在海洋沉积物中。自从IP25被发现以来,越来越多的研究者对其指示海冰变化的应用进行了深入的研究。本文首先总结了重建古海冰的传统指标和限制性并介绍了IP25指示海冰的原理、由定性到定量的发展以及存在的局限性。然后归纳了利用IP25重建北极地区海冰分布和变化的实例研究,涵盖了北冰洋中心、陆架边缘海、河口以及亚北极地区不同空间海域,跨越了近现代、全新世、第四纪以及中新世不同时间尺度。其中,近现代的海冰重建结果与海冰的卫星观测数据取得了很好的相关性,为古海冰的重建提供了基础;古海冰的重建为数值模拟古气候以及预测未来海冰变化趋势提供了重要依据。
The Arctic sea-ice cover is declining with global warming, which bears significant impacts on global thermohaline circulation, biogeochemistry process and climate changes. To comprehensively understand the Arctic environment and to predict its changes in the future, it is important to reconstruct the paleo-sea ice variability for the region. In the recent decade, a newly developed sea-ice proxy IP25(an Ice Proxy with 25 carbon atoms), monounsaturated highly branched isoprenoid(HBI) alkene biosynthesized specifically by sea-ice associated diatoms only found in Arctic and sub-Arctic marine sediments, has been universally used to reconstruct the sea-ice variability. Since the first use of IP25 as a proxy for paleo-sea ice, more and more laboratories have measured this biomarker in Arctic and subarctic sediments to verify the application of IP25 to sea ice reconstruction. In this review, we firstly summarized the traditional indicators for sea ice reconstruction and their limitations, and then described is the scientific basis for IP25 proxy and its development from qualitative description to quantitative calculation as well as it limitations. Secondly, we summarized the case studies of using IP25 to reconstruct the distribution and variation of the sea ice. These studies spatially cross the Central Arctic Ocean, Arctic marginal seas, Arctic estuaries and the subarctic regions, and temporally cover the time scales of the modem times, the Holocene, the Quaternary and the Miocene. A good linear correlation between reconstructed modern sea-ice concentrations by using IP25 and satellite-derived spring sea ice concentrations has been observed, providing the basis for paleo-sea ice reconstruction, which may provide important evidence and insight for numerical simulation of paleoclimate and future sea ice prediction.
作者
郝伟杰
肖晓彤
赵美训
HAO Weijie;XIAO Xiaotong;ZHAO Meixun(Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China;Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China)
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2019年第4期56-65,共10页
Marine Geology & Quaternary Geology
基金
国家自然科学基金面上项目“北冰洋西部过去130ka海冰演变记录及其对碳循环的影响”(41876214)