Deglacial pulses of deep-ocean silicate reveal enhanced Southern Ocean upwelling

来源 :2015中国极地科学学术年会 | 被引量 : 0次 | 上传用户:absyou
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  Growing evidence suggests that the low atmospheric CO2 concentration of the ice ages resulted from enhanced storage of CO2 in the ocean interior,largely as a result of changes in the Southern Ocean.Early in the most recent deglaciation,a reduction in North Atlantic overturning circulation seems to have driven CO2 release from the Southern Ocean,but the mechanism connecting the North Atlantic and the Southern Ocean remains unclear.Biogenic opal export in the low-latitude ocean relies on silicate from the underlying thermocline,the concentration of which is affected by the circulation of the ocean interior.Here we report a record of biogenic opal export from Polar Antarctic Zone that shows pronounced opal maxima during each glacial termination over the past 638 ka, corresponding to the opal peaks of North Atlantic ODP 658.These opal peaks are consistent with a strong deglacial reduction in the formation of silicate-poor glacial North Atlantic intermediate water(GNAIW).We interpret the opal peaks in north Atlantic and PAZ as resulting from the enhanced Southern Ocean upwelling and the ratio of silicate-rich AABW in the intensive mixed upwelling.We argue that this is a more pausible senario than a mixing of silicate-rich abyssal waters into the low latitude Atlantic thermocline.
其他文献
光学湍流的预报在光学工程应用中具有重要意义。天文观测站在选址、设计和运行时都需要监测台址区域内光学湍流强度的时空分布。近年来,我国在南极的天文项目快速发展,对南极区域的大气光学湍流时空分布的研究是一项亟需开展的工作。探空测量大气光学湍流耗费巨大的人力、物力和财力,并且测量方式受到环境的极大制约。介绍了基于光学湍流参数化方案,利用中尺度数值天气预报模式(WRF)预报大气光学湍流强度廓线的方法。通过在
中国之星小望远镜CSTAR是中国制造的第一台南极天文望远镜.2008年3月至7月,CSTAR 观测南天极附近天区并获得约20,000 颗星的i 波段光变曲线.通过分析这些光变曲线,我们认证了(1)53个双星系统,包括24个分离双星、8个半相接双星、18个密近双星和3个椭球变星(ApJS,2015,217,28);(2)10个类木行星候选体(ApJS,2014,211,26).我们求解了掩食双星和行
会议
Quantitative and qualitative examinations of phytoplankton species composition were studied on the investigation data in the Arctic and Antarctic Ocean during 1989-2014.Using light and electron micros
会议
甲壳类动物在海洋或淡水中占有不可或缺的地位,是鱼、虾类的主要天然饵料,得到广泛关注,尤其是年龄鉴定方面。本文在简要介绍传统鉴龄方法的基础上,详尽阐述了脂褐素的相关内容,尤其是对脂褐素鉴龄的两种方法:组织学技术及生物化学技术,进行了详细总结;并提出今后的研究展望,以期为进一步开展甲壳类动物年龄鉴定提供思路,为该物种的管理和生态系统的变动提供参考。
中国自2009/2010 渔季起对南极磷虾(Euphausia superba)进行商业性捕捞,虽然捕捞产量已达到6 万余吨,但技术瓶颈仍是制约我国南极磷虾产业发展的关键因素.拖网网板的水动力性能是影响南极磷虾拖网捕捞效率和渔获品质的重要因素.为提高网具在低拖速下的扩张性能,自主设计了一种南极磷虾专用拖网网板,并分析其在不同迎流冲角状态下的水动力性能.水槽模型实验结果表明:升力系数(CL)和升阻比
会议
CH4 and N2O fluxes has important influence on climate change.While many studies measurements of CH4 and N2O emissions have been made in tropical wetlands,few research were studied in high arctic tundr
会议
冬季南极磷虾群昼夜垂直移动方面的知识可为其渔场形成机制研究提供基础数据,并为其越冬策略研究提供参考。基于2013年冬季南乔治亚岛南极磷虾渔业调查期间收集的相关数据,本研究对冬季南乔治亚岛南极磷虾群昼夜垂直移动进行了研究。结果表明,磷虾群平均深度维持在表层以下100-300m 之间,磷虾群最深出现在日升时分,而最浅则出现在夜间时分;随7-9月份的推移,磷虾群所处水层不断加深。夜间、白天和黄昏时段磷虾
提取极地多学科数据的公有信息和特有考察信息,对极地多学科数据库系统构建基于本体的知识系统,形成完成的极地学科数据知识图谱;在此基础上形成多学科数据库系统数据索引,实现极地科学数据的实时响应查询和数据的动态维护。感谢复旦大学计算机科学技术学院大数据与知识工程实验室的大力支持!
会议
The cause of massive blooms of Ethmodiscus rex laminated diatom mats(LDMs)in the eastern Philippine Sea(EPS)during the Last Glacial Maximum(LGM)remains uncertain.In order to better understand the mech
The close resemblance of magnetic susceptibility of Scotia Sea sediments and Antarctic ice core dust records provoke the assumption of Patagonia dust as the main contributor to the magnetic signal in
会议