Collaborative Research: P2C2--Interrogating the Free Troposphere during the Last Deglaciation

该项目的目的是提供第一个全球尺度的自由对流层温度和动力学限制，自由对流层包括大约2 - 18公里的高度。具体来说，研究人员将使用新的同位素测量和三维（3D）全球建模来重建和解释上一次冰消期（距今18,000至8,000年）的高海拔大气温度和环流变化。该项目将使用一种新的来自冰芯记录的示踪剂来生成古温度记录，以揭示地球历史上最近重大气候转变期间对流层的状况及其与平流层的相互作用。研究目标包括在一段时间内，包括几个突发的气候变化事件限制自由对流层的热演化;测试模拟的自由对流层对轨道和温室气体强迫的响应;并测试平流层到对流层的交换动力学在主要的气候转变。这种结合的测量建模研究将限制在最近的全球变化的主要情节，在不同的气候边界条件下，当环流模式转移的海拔古气候。潜在的更广泛的影响包括在最后一次冰消期间建立一个新的自由对流层温度记录。应用一种新的同位素示踪剂来研究平流层-对流层交换的动力学对古气候研究具有潜在的变革意义。其他更广泛的影响包括研究人员参与STEM外联活动，作为其正在进行的活动的一部分，包括与女童子军一起参加该部门在赖斯大学举行的年度地球日。该项目将培养一名本科生和两名研究生，并支持两名早期职业研究人员。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to provide the first global-scale constraints on temperature and dynamics of the free- troposphere- which comprises altitudes ranging from about 2 - 18 km. Specifically, the researcher will use new isotopic measurements and 3 Dimensional (3D) global modeling to reconstruct and interpret high-altitude atmospheric temperature and circulation changes during the last deglaciation (18,000 to 8,000 years before present). This project will use an emerging tracer from ice-core records to generate a paleo-temperature record that will reveal the state of the troposphere and its interaction with the stratosphere across the most recent major climate transition in Earth history. Research goals include constraining the thermal evolution of the free troposphere during a time period that includes several episodes of abrupt climate change; testing modeled free-troposphere responses to orbital and greenhouse-gas forcing; and testing stratosphere-to- troposphere exchange dynamics across major climate transitions. This combined measurement-modeling study will constrain the paleoclimate at altitude during the most recent major episode of global change, when circulation patterns shifted under different climatic boundary conditions. The potential Broader Impacts include developing a new temperature record of the free troposphere during the last deglaciation. The application of a new isotopic tracer to investigate the dynamics of stratosphere-troposphere exchange is potentially transformative for paleoclimate research. Other broader impacts include participation of the researchers in STEM outreach events as part of their ongoing activities, including participation in the department’s annual Earth Day at Rice University with the Girl Scouts. The project will train one undergraduate and two graduate students, and support two early career researchers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.