Sub-annual climate variability during the last deglaciation: New views from coralline biogeochemistry

末次冰消期的亚年气候变化：珊瑚生物地球化学的新观点

• 批准号: NE/E002080/1
• 负责人: Rachael James
• 金额: $ 2.1万
• 依托单位: The Open University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FE002080%2F1
• 关键词: Sub; annual; climate; variability; during

If we travelled back in time some 18 000 years, we would hardly recognise our planet. Many parts of the Northern Hemisphere that are densely populated today were frozen wastes: glaciers covered the cities of New York and Berlin, and the ground where London and Paris would become established was permanently frozen. Not long after however, this ice began to melt. The oceans were flooded with fresh water, causing sea level to rise and changing the pattern of ocean circulation. The question that we want to answer in this proposal, is what effect did this change in the pattern of circulation have on Earth's climate? The problem is that direct measurements of our climate (for example, temperature) extend back no further than the past few hundred years, so such information must instead be reconstructed from so-called proxies, or 'substitutes'. Corals are particularly useful proxies, because they can be accurately dated and their chemical composition reflects a number of important environmental parameters, such as the temperature of the water in which they grew. Here, we propose to obtain records of the variation in the chemical composition of coral skeletons from Tahiti that are between 20 000 and 10 000 years old. What is unique, is that we will use new laser technology that enables us to obtain records at extremely high resolution (a few days to a few months). This means that we will be able to capture the short-term events that can influence the transition from glacial to warmer conditions on Earth.

如果我们回到了大约18 000年的时间里，我们几乎不会认识到我们的星球。如今，人口稠密的北半球的许多地区都是冰冻的废物：冰川覆盖了纽约和柏林的城市，伦敦和巴黎建立的地面被永久冷冻。然而，不久之后，这种冰开始融化。海洋充满了淡水，导致海平面上升并改变海洋循环模式。我们想在此提案中要回答的问题是，这种循环模式的变化对地球气候有什么影响？问题在于，我们气候的直接测量（例如温度）不超过过去几百年，因此必须从所谓的代理或“替代”中重建此类信息。珊瑚是特别有用的代理，因为它们可以准确地进行过时，并且它们的化学成分反映了许多重要的环境参数，例如它们生长的水的温度。在这里，我们建议获取大溪地珊瑚骨骼的化学成分变化的记录，年龄在20 000至10 000年之间。独特的是，我们将使用新的激光技术，使我们能够以极高的分辨率（几天到几个月）获得记录。这意味着我们将能够捕获可能影响地球上冰川到温暖条件的过渡的短期事件。