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，以生成具有十年分辨率的3000年热带西非水文变化记录。 此外，还将制作第一份关于10，000至25，000年之间大气放射性碳变化的热带记录。 将从这些沉积物中分析各种气候代用指标，以产生古水文时间序列。 将从纹层测定陆生植物的木炭的年代，以生成用于放射性测年的D14C校准曲线。 干旱发生的时间和干旱的自然变化对该区域（西非）很重要。 更好地了解该地区的水文历史如何与其他地区的类似记录相关，将提高我们对气候系统的整体认识，并使我们能够回答有关低纬和高纬之间的相互关系以及海洋和陆地气候相互作用的许多问题。 在冰期到冰消期大气放射性碳变化的真实形状将是放射性碳测年的一个重要进展。