古气候:海洋潮和海因里希事件
Brian K Arbic1, Douglas R Macayeal, Jerry X Mitrovica
1Program in Atmospheric and Oceanic Sciences, Princeton University, PO Box CN710, Sayre Hall, Princeton, New Jersey 08544-0710, USA. arbic@splash.princeton.edu
Nature
|November 27, 2004
概括
在最后一个冰河时代,拉布拉多海的异常大的海洋潮与被称为海因里希事件的巨大的冰山排放相吻合. 这些强大的潮可能在释放大型冰山到北大西洋中发挥了关键作用.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 四年纪地质学四年纪地质学
背景情况:
- 最后一个冰河时代经历了显著的气候变化,标志着定期,大规模释放到北大西洋的冰碎片.
- 这些被称为海因里希事件的突然气候变化主要来自拉布拉多海,并具有全球影响.
研究的目的:
- 为了调查海在拉布拉多海在海因里希事件期间的作用.
- 探索潮动力学与冰山舰队的解放之间的潜在联系.
主要方法:
- 对地质记录的分析,表明冰上飞的碎片沉积.
- 拉布拉多海过去的海洋潮范围的重建.
主要成果:
- 在海因里希事件发生时,在拉布拉多海内发现了异常大的海洋潮.
- 观察到高潮活动时期和冰上飞碎片沉积之间存在强烈的相关性.
结论:
- 拉布拉多海的海洋潮在最后一个冰河时代的海因里希事件期间显著放大.
- 这些增强的潮很可能起到了催化剂的作用,触发了冰川大规模的冰山舰队的释放.
相关概念视频
01:50Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
01:06Tidal Forces
The origin of Earth's ocean tides has been a subject of continuous investigation for over 2000 years. However, the work of Newton is considered to be the beginning of the proper understanding of the phenomenon. Ocean tides are the result of gravitational tidal forces. These same tidal forces are present in any astronomical body; they are responsible for the internal heat that creates the volcanic activity on Io, one of Jupiter's moons, and the breakup of stars that get too close to black holes.
01:30Marine Microbial Ecology
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...
01:18Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...