P2C2: Collaborative Research: Transient forcing of the Local Last Glacial Maximum in the tropical Peruvian Andes

P2C2：合作研究：热带秘鲁安第斯山脉当地末次盛冰期的瞬时强迫

• 批准号: 2002476
• 负责人: Joseph Licciardi
• 金额: $ 16.56万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2002476&HistoricalAwards=false
• 关键词: P2C2; Collaborative; Research; Transient; forcing

The geological history of tropical glaciers can provide scientists an important perspective from the past on how Earth’s climate system responds to human activity. This project will look to the geological record of tropical glaciers in the Andes Mountains for a perspective on past changes in the glacial ice extent and how these changes may relate to records of changes in the atmospheric conditions during periods of abrupt climate change. These records of glacial activity will help place the current state of rapidly retreating ice margins in the tropics in a longer-term context that extends well beyond the instrumental record. Finally, by integrating multiple archives of past climates and modeling the causes of tropical high elevation climate changes, this work will improve our understanding of abrupt global climate changes because these regions had much larger glaciers in the past. By determining ages on the rocks that were transported by the ancient glaciers and combining analyses of lake sediments deposited continuously below the glaciers, this research will provide a detailed record of how much the glaciers changed and when. The research team will incorporate climate model simulations to test the causes of tropical climate changes and how they relate to high latitude warming and cooling events. This project will train 3 graduate students, and at least 4 undergraduate students. The project team will improve K-12 science education and engagement by exposing teachers and students (both local and abroad) to research through the GLOBE program (Global Learning and Observation to Benefit the Environment). The team also will partner with INAIGEM in Peru to broaden project impact, and help with the mission of educational capacity building. This project will evaluate tropical glacial variability during the local Last Glacial Maximum (LLGM) to better understand how low latitude temperature variability and the hydrologic cycle were modulated by ocean and atmospheric processes. This research has the following objectives: 1) determine robust ages of moraines using terrestrial cosmogenic radionuclide (TCN) dating methods to provide information about both the timing and extent of multiple LLGM ice limits; 2) rigorously evaluate centennial-scale records of glacial flour flux using high-resolution geochemical archives from the recently acquired Lake Junín drill-core record; 3) test the scale and climatic forcing of LLGM climate variability using climate model simulations; 4) test the scale of LLGM glacier variability responses to climatic forcing using energy and mass-balance models. This research will produce multi-proxy, centennial-scale records of mountain glaciation in Peru spanning the LLGM, at a scale and resolution that has not yet been achieved. This resolution will be sufficient to make comparisons with ice cores from Greenland, Antarctica, and the tropical Andes, as well as decadal-scale speleothem-based stable isotope records of hydroclimate changes from the same (Lake Junín) catchment. This will allow for a collective evaluation of mountain glacier archives and other regional records of past atmospheric variability that will improve our understanding of the role of the tropics in abrupt global change events on millennial timescales. These records will provide insight on the sensitivity of tropical glaciers to a range of climate conditions, both atmospheric and oceanic, and particularly how the tropical climate system responds to meltwater forcing. Ultimately, these records will inform how the tropical hydrologic cycle drives glacial-interglacial cycles in both the low and high latitudes.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.

热带冰川的地质历史可以为科学家提供过去关于地球气候系统如何应对人类活动的重要观点。该项目将探讨安第斯山脉山脉中热带冰川的地质记录，以了解冰川冰范围的过去变化，以及这些变化如何与突然气候变化期间大气条件变化的记录有关。这些冰川活性的记录将有助于将快速撤退的冰河边缘迅速撤退的状态在长期的背景下，远远超出了仪器记录。最后，通过整合过去气候的多个档案并建模热带高海拔气候变化的原因，这项工作将提高我们对突然的全球气候变化的理解，因为这些地区过去的冰川质量要大得多。通过确定古老冰川运输的岩石的年龄，并结合了冰川下方连续沉积的湖泊沉积物的分析，这项研究将提供详细的记录，以了解冰川发生了多少变化和何时发生变化。研究团队将结合气候模型模拟，以测试热带气候变化的原因以及它们与高纬度变暖和冷却事件的关系。该项目将培训3名研究生，至少4名本科生。项目团队将通过揭露教师和学生（本地和国外）的研究（全球学习和观察以使环境受益）来改善K-12科学教育和参与。该团队还将与秘鲁的Inaigem合作，以扩大项目影响，并帮助建立教育能力的使命。该项目将评估局部最后一次冰川最大（LLGM）期间的热带冰川变异性，以更好地了解海洋和大气过程如何调节低纬度温度可变性和水文周期。这项研究具有以下目的：1）使用陆地宇宙射核苷（TCN）约会方法确定肌脱素的稳健年龄，以提供有关多个LLGM冰限制的时间和程度的信息； 2）严格评估了最近获得的朱恩湖钻核记录中的高分辨率地球化学档案，对冰川玻璃通量的百年纪录记录进行了严格评估； 3）使用攀登模拟模拟LLGM攀爬变异性的尺度和杂交强迫； 4）测试使用能量和质量平衡模型对杂交强迫的LLGM冰川变异性响应的比例。这项研究将以尚未实现的规模和解决方案产生秘鲁山区山冰川的百年纪念记录。该分辨率足以与来自格陵兰，南极和热带安第斯山脉的冰核以及基于deCALCALE的speleothem稳定同位素记录的冰芯进行比较，从而可以从同一（Junín）流域进行氢化气候变化的稳定同位素记录。这将允许对山地冰川档案馆和其他大气变异性的其他区域记录进行集体评估，这将提高我们对热带变革事件在千禧年时标准中的作用的理解。这些记录将提供有关热带冰川对大气和海洋气候条件范围的敏感性的见解，尤其是热带气候系统如何对融合水的强迫做出反应。最终，这些记录将告知热带水文循环如何在低纬度和高纬度地区驱动冰川间冰期循环。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响审查标准来评估来获得的支持。