A High-Resolution Record of Holocene Climate Variability from Lake Edward, Central Africa

中非爱德华湖全新世气候变化的高分辨率记录

• 批准号: 0314832
• 负责人: Tom Johnson
• 金额: $ 19.09万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0314832&HistoricalAwards=false
• 关键词: Resolution; Record; Holocene; Climate; Variability

Tropical Africa is one of three major centers of deep atmospheric convection that energize the Earth's atmosphere through latent heating. There is much to be learned about how tropical Africa's climate contributes to global climate. Lake Edward is a 120-m deep rift lake situated on the eastern edge of the Congo basin, and is perfectly situated to record climate variability in one of the most immense monsoon systems on the planet. The research will generate a decade- to century-scale record of moisture balance based on Holocene sediments from Lake Edward. The main goal of this research is to understand the causes of multi-decade to millennial-scale Holocene climate events in Africa. The research is designed to build upon and refine previous studies by focusing high-resolution analyses on time intervals previously not analyzed in the Lake Edward region: the last 1,000 years and the early Holocene. Results from these analyses will complement ongoing high-resolution studies of the interval 1,000 to 5,000 yr BP in Lake Edward. The combined dataset will allow testing of linkages between continental Africa, the tropical oceans, high-latitudes, and external forcing (i.e. solar variability) at a variety of time-scales. The researcher will develop high-resolution geochemical and stable isotopic stratigraphies from sediment cores already taken from both Lake Edward and nearby crater lakes. Results of this research could significantly advance our understanding of tropical paleoclimate dynamics. This research relates to several areas of paleoclimate research priorities, including the need for analysis of the full range of climate variability over the past 11,000 years from an important monsoon system, and the testing of regional patterns and phasing of climate change within tropical Africa and the global climate system.

热带非洲是深层大气对流的三个主要中心之一，通过潜热加热为地球大气提供能量。关于热带非洲的气候对全球气候的影响，还有很多东西需要了解。爱德华湖是一个120米深的裂谷湖，位于刚果盆地的东部边缘，非常适合记录地球上最巨大的季风系统之一的气候变化。这项研究将根据爱德华湖全新世沉积物产生一个十年到一个世纪的水分平衡记录。这项研究的主要目标是了解非洲数十年至数千年规模的全新世气候事件的原因。这项研究旨在建立和完善以前的研究，重点是对爱德华湖地区以前没有分析过的时间间隔进行高分辨率分析：过去1,000年和全新世早期。这些分析的结果将补充正在进行的爱德华湖1,000至5,000年BP的高分辨率研究。综合数据集将允许在各种时间尺度上测试非洲大陆、热带海洋、高纬度和外部强迫（即太阳变率）之间的联系。研究人员将从爱德华湖和附近的火山口湖的沉积物岩心中开发高分辨率的地球化学和稳定同位素地层。这一研究成果将大大提高我们对热带古气候动力学的认识。这项研究涉及古气候研究的几个优先领域，包括需要分析过去11 000年来一个重要的季风系统造成的各种气候变化，并测试热带非洲和全球气候系统内气候变化的区域模式和阶段。