Varved Records of Decade- to Century-Scale Climate Variability in the Tropical Atlantic Sector

热带大西洋区域十年至百年尺度气候变化的变化记录

• 批准号: 0214525
• 负责人: Jonathan Overpeck
• 金额: $ 16.7万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0214525&HistoricalAwards=false
• 关键词: Varved; Records; Decade; Century; Scale

This award is to analyze sediments from Lake Bosumtwi to generate a record of tropical West African hydrologic variability back to 3000 years with decadal resolution. In addition, the first tropical record of atmospheric radiocarbon change between 10,000 and 25,000 years will be produced.Previous field work has secured laminated core material back to about 25,000 years at Lake Bosumtwi. A variety of proxy indicators of climate will be analyzed from these sediments to produce a paleohydrologic time series. Charcoal from terrestrial plants will be dated from the varved layers to generate a D14C calibration curve for radiometric dating. The timing of droughts and the natural variability of droughts to this region (West Africa) are important. Better understanding of how the hydrologic history of the region relates to similar records from other regions will advance our overall knowledge of the climate system and allow us to answer many questions regarding interrelationships between low and high latitude and marine and terrestrial climate interactions. The true shape of the atmospheric radiocarbon variation during glacial to deglacial times will be an important advancement for radiocarbon dating.

该奖项旨在分析Bosumtwi湖的沉积物，以通过衰老的分辨率产生热带西非水文变异性的记录。 此外，将产生大气放射性碳变化在10,000到25,000年之间的第一个热带记录。预防现场工作使Bosumtwi湖的层压核心材料恢复了约25,000年。 将从这些沉积物中分析各种气候的代理指标，以产生古水域时间序列。 陆生植物的木炭将从静动层进行日期，以生成D14C校准曲线以进行辐射测定。 干旱的时机和对该地区（西非）的干旱的自然变化很重要。 更好地理解该地区的水文历史与其他地区的类似记录的关系将提高我们对气候系统的整体知识，并使我们能够回答有关低纬度和高纬度与海洋以及海洋和陆地气候相互作用之间相互关系的许多问题。 在冰川时期，在冰川时期，大气放射性碳变异的真实形状将是放射性碳日期的重要进步。