P2C2:Collaborative Research: A Speleothem Study of the Paleoclimatology of the Yucatan Peninsula: Testing Modes and Causes of Variability in the North American Tropics

P2C2：合作研究：尤卡坦半岛古气候学的洞穴研究：测试北美热带地区变化的模式和原因

• 批准号: 1664316
• 负责人: Martin Medina-Elizalde
• 金额: $ 10.26万
• 依托单位: Auburn University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1664316&HistoricalAwards=false
• 关键词: P2C2; Collaborative; Research; Speleothem; Study

This project's goal is to reconstruct low latitude precipitation variability, from interannual to orbital time scales, to better understand hydrological responses to meso and large-scale atmosphere and ocean dynamics, external forcing, and feedbacks in the Yucatan Peninsula (YP). The mechanisms proposed for driving suborbital scale climate regimes in the region include ENSO, tropical cyclogenesis and shifts in precipitation associated with movements of the Inter Tropical Convergence Zone (ITCZ), but available paleoclimate records are contradictory in terms of causal factors.The project could potentially improve rainfall sensitivity estimates that would represent an empirical assessment independent of models. Current international climate model estimates of precipitation changes in the region by the end of this century vary over a significant range (-50% to +9% relative to today). The project would also support an underrepresented minority early-career scientist and provide an early experience in research to several undergraduate students. In addition, the research team will produce educational materials and exhibits for a general audience in Spanish and English language versions.The research team will use speleothems from caves of the YP to reconstruct the character of hydrological variability in the region during the Holocene, the last glacial interval, marine isotope stage (MIS) 5, and MIS 7 to 9. In particular, the team will make quantitative reconstructions of precipitation changes based on delta-18Oxygen isotopes in stalagmites. In combination with available lacustrine records from the YP, local speleothem records may provide a unique opportunity to quantitatively reconstruct the precipitation to evaporation balance in the region. Quantitative high-resolution Holocene and Late Pleistocene precipitation records will: 1) provide quantitative estimates of past rainfall variability; 2) test the relationship between rainfall variability and shifts in mean ITCZ; 3) investigate the role of ENSO, tropical sea surface temperatures and cyclones in driving climate regimes in the YP; and 4) provide estimates of the sensitivity of tropical hydrology.The researchers will leverage an active collaboration with the Rio Secreto Reserve, a commercial enterprise that leads ~50,000 tourists through a large, partially submerged cave system on the east coast of the YP for education and outreach aims. The cave system of Rio Secreto represents an ideal cave system for reconstructing precipitation changes from stalagmites in the region extending approximately 300,000 years before the present.

该项目的目标是重建从年龄段到轨道时间尺度的低纬度降水量变异性，以更好地了解对中索和大规模气氛和海洋动力学的水文反应，外部强迫以及尤卡坦半岛（YP）的反馈。 The mechanisms proposed for driving suborbital scale climate regimes in the region include ENSO, tropical cyclogenesis and shifts in precipitation associated with movements of the Inter Tropical Convergence Zone (ITCZ), but available paleoclimate records are contradictory in terms of causal factors.The project could potentially improve rainfall sensitivity estimates that would represent an empirical assessment independent of models.当前的国际气候模型估计到本世纪末，该地区降水变化的变化在很大的范围内（相对于今天的范围为-50％至 +9％）。 该项目还将支持代表性不足的少数族裔早期科学家，并为几位本科生提供早期研究经验。 此外，研究团队将以西班牙语和英语版本为普通观众生产教育材料和展览。研究小​​组将使用来自YP洞穴的Speleothems来重建全新世期间该地区水文变异性的特征，最后一个冰川间隔，海洋同位素阶段（MIS MIS）5到9。石质中的同位素。 结合YP的可用湖泊记录，当地的Speleothem Records可能会提供独特的机会，以定量地重建该地区蒸发平衡的降水量。 定量高分辨率全新世和晚更新世降水记录将：1）提供过去降雨变异性的定量估计； 2）测试降雨变异性与平均iTCZ变化之间的关系； 3）研究ENSO，热带海面温度和旋风在推动YP气候方案中的作用； 4）提供了热带水文学敏感性的估计。研究人员将利用与里约秘密储备的积极合作，这是一家商业企业，通过YP东海岸的大型，部分淹没的洞穴系统，使约50,000名游客用于教育和外展目标。里约热内卢的洞穴系统代表了一个理想的洞穴系统，用于重建从现在延伸约300，000年的区域中降水的变化。