Collaborative Research: Lake Peten-Itza Drilling Project, Guatemala: A Terrestrial Archive of Northern Neotropical Climate and Environmental Change for the Last Climate Cycle

该合作项目的研究人员试图使用GLAD 800（全球湖泊钻探800）系统从危地马拉北方的佩滕伊察湖获取沉积物岩心，以研究晚更新世和全新世期间中美洲低地的气候变化，时间尺度从几十年到几千年不等。研究人员假设，大西洋热带辐合带（ITCZ）的平均纬向位置的变化是北方低地新热带地区在年际到多千年时间尺度上降雨变化的原因。ITCZ是赤道5度以内的区域，信风汇聚形成低气压，增加降水并影响全球环流。耦合的大气环流模式表明，北大西洋高纬度地区的气候和环流变化非常敏感。具体而言，研究人员将通过将Peten-Itza湖沉积物核心中的降雨和径流代理与委内瑞拉北方Cariaco盆地的降雨和径流代理相关联来建立海洋-陆地联系，以确定区域降水变化。反过来，将把Peten-Itza和Cariaco的记录与北大西洋高纬度地区的代用信号进行比较，以评估与该区域的联系。据信，在亚千年的时间尺度的古气候档案的陆地-海洋-冰的相关性，可以用来破译的北方新热带水文循环的历史，它与大西洋ITCZ的关系，并在高纬度北大西洋气候的联系。为此，根据详细的地震勘测，在Peten-Itza湖确定了六个主要钻探地点。Peten-Itza科学钻探项目将通过与危地马拉大学（UVG和UNSC）的同事在研究议程上进行持续，密切和积极的合作，具有强大的教育和外联部分。美国和危地马拉的本科生和研究生都将直接参与这项研究。

The researchers in this collaborative project seek to use GLAD800 (the Global Lake Drilling 800) system to retrieve sediment cores from Lake Peten-Itza in northern Guatemala to study climate variability in lowland Central America during the late Pleistocene and Holocene on time scales ranging from decades to millennia. The researchers hypothesize that changes in the mean meridional position of the Atlantic inter-tropical convergence zone (ITCZ) are responsible for rainfall variations in the northern lowland Neotropics on interannual to multi-millennial time scales. The ITCZ is a region within 5 degrees of the equator where the trade winds converge to form low atmospheric pressure, enhancing precipitation and influencing global circulation. Coupled general circulation models indicate high sensitivity to climate and circulation changes in the high-latitude North Atlantic. Specifically, the researchers will establish marine-terrestrial linkages by correlating rainfall and runoff proxies in sediment cores from Lake Peten-Itza with those from the Cariaco Basin, northern Venezuela, to determine regional precipitation changes. In turn, the Peten-Itza and Cariaco records will be compared with proxy signals from the high latitudes of the North Atlantic to assess linkages with that region. It is believed that terrestrial-marine-ice correlations of paleoclimate archives at sub-millennial time scales can be used to decipher the history of the northern Neotropic hydrologic cycle, its relation to the Atlantic ITCZ, and linkages to climate in the high-latitude North Atlantic. To accomplish this, six primary drilling sites have been identified in Lake Peten-Itza on the basis of detailed seismic surveys. The Peten-Itza Scientific Drilling Project will have a strong education and outreach component through ongoing, close, and active collaboration with colleagues at Guatemalan universities (UVG and UNSC) in the research agenda. Both U.S. and Guatemalan undergraduate and graduate students will be directly and significantly involved in the research.