当前位置: 首页 > 开放交流 > 学术讲座
学术讲座

Luncheon Seminar #250: Bipolar control on millennial atmospheric CO2 changes over the past glacial cycle

发布时间:2023/12/26     浏览次数:
时间:2024-1-2 (星期二) 12:00-12:40
地点:周隆泉楼二楼咖啡厅
主讲人:于际民 研究员
来访单位:崂山实验室
邀请人:蔡平河 教授
联系人:黄迎 2181571

报告摘要:

Ice-core measurements show diverse atmospheric CO2 variations – increasing, decreasing or remaining stable – during millennial-scale North Atlantic cold periods called stadials. The reasons for these contrasting trends remain elusive, because they are difficult to be explained by Southern Ocean processes alone. Ventilation of carbon-rich deep oceans can profoundly affect atmospheric CO2, but its millennial-scale history is poorly constrained. In this talk, I will show a high-resolution deep-water acidity record from the Iberian Margin in the North Atlantic, a unique setting that allows us to construct a robust chronology for confident comparisons between marine and ice-core records. The new data combined with ice-core CO2 records reveal multiple ocean ventilation modes involving an interplay of the two polar regions, rather than by the Southern Ocean alone. These modes governed past deep-sea carbon storage and atmospheric CO2 variations on millennial timescales. I will also share some progress in my group, including new approaches (e.g., foraminiferal boron isotopes for surface-water pCO2 reconstructions) to investigate polar ocean carbon cycle and ongoing research to reconstruct long-term ocean acidity conditions using recently drilled sediments from IODP Expedition 397.


个人介绍:

于际民博士,崂山实验室研究员。在南京大学地球科学系获得本科(1999)和硕士学位(2002),在剑桥大学获得博士学位(2007)。先后在英国剑桥大学、美国哥伦比亚大学、美国劳伦斯弗莫尔国家实验室和澳大利亚国立大学地球科学学院(历任讲师、副教授、教授职位)从事科研和教学工作,2021年起就职于崂山实验室。于际民博士长期从事古海洋、古气候研究,开发和利用海洋生物碳酸盐微量元素和同位素替代指标(如, 有孔虫B/Ca),重建不同时间尺度(轨道、千年)海洋碳酸盐体系演化历史,并结合模拟手段探究相关调控机制及其对大气CO2和气候的影响。近期工作侧重于IODP EXP397航次所获岩芯样品分析,以期提升我们对不同气候态条件下海洋碳循环调控机理的认识。