Climatic and Vegetational Oscillations During the Last Glacial-Interglacial Transition in Alaska

阿拉斯加末次冰期-间冰期转变期间的气候和植被振荡

• 批准号: 9619583
• 负责人: Feng Sheng Hu
• 金额: $ 16.49万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-01 至 1998-11-10
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9619583&HistoricalAwards=false
• 关键词: Climatic; Vegetational; Oscillations; During; Last

9619583 Hu Evidence is compelling from the circum-North Atlantic and from other parts of the globe that climatic warming during the last glacial-interglacial transition (LGIT) was punctuated by short-lived reversals to near-glacial conditions. In Alaska paleoecological and stable-isotope data from scattered sites strongly suggest the existence of short-lived climatic events during the LGIT. This PALE/ARCSS award supports a project to acquire high-temporal resolution records of vegetation and climate during the LGIT by analyzing a suite of proxy indicators in sediment cores from lakes across three sub-regions of Alaska. Vegetational reconstructions will be based on pollen, spore, and plant-macrofossil records supplemented by carbon-content and magnetic-susceptibility stratigraphies. The complementary properties of these proxies will allow the identification of the most plausible paleoenvironmental scenarios. The results from this project will be used to assess the timing, geographic extent, character, and magnitude of climatic and vegetational oscillations during the LGIT in Alaska. As part of the longitudinal (circumarctic) database from PALE and the latitudinal database form PEP-I, paleorecords from this project should offer insights into the linkages of North Pacific high-latitudes to the global climate system and the mechanisms causing abrupt climatic changes.

9619583来自环北大西洋和全球其他地区的HU证据令人信服地表明，上一次冰川-间冰期过渡期间的气候变暖被短暂的向近冰川条件的逆转所打断。在阿拉斯加，来自分散地点的古生态和稳定同位素数据有力地表明，在LGIT期间存在短暂的气候事件。这项PALAR/ARCS奖支持一个项目，该项目通过分析阿拉斯加三个分区域湖泊沉积物岩芯中的一套替代指标，获得LGIT期间植被和气候的高时间分辨率记录。植被重建将以花粉、孢子和植物大型化石记录为基础，辅之以碳含量和磁化率地层学。这些替代物的互补性将使我们能够识别最合理的古环境情景。该项目的结果将用于评估阿拉斯加LGIT期间气候和植被振荡的时间、地理范围、特征和大小。作为PALE的纵向(北极圈)数据库和PEP-I的纬度数据库的一部分，该项目的古记录应有助于深入了解北太平洋高纬度与全球气候系统的联系以及造成气候突变的机制。