P2C2: A 20,000 Year Ice Core-Derived Record of Paleoclimate and Environmental Variability in the Tropical Andes: Nevado Huascaran, Cordillera Blanca, Peru

研究人员打算从海拔6050米的山坳（即两个山峰之间的山脊最低点）向基岩钻两个165米长的岩心，从海拔6756米的南峰山顶钻两个70米长的岩心。尽管在1993年对该峡谷进行了调查，并成功地钻到了基岩上，但不可能在山顶进行钻探，而且只有几种测年技术可以帮助建立过去2万年的有效时间尺度。来自Huascaran的稳定同位素记录将提供对流层中温度和降水的历史，该地点靠近亚马逊盆地，可以通过分析生物参数（微生物种群、花粉和甲烷浓度）来重建广阔雨林的环境变化。研究人员的目标如下：(1)记录和描述气候和环境的突变，重点是中全新世事件和冰川消融；(2)评估过去一个世纪气候和环境如何响应人为强迫而发生变化；(3)为每个冰芯建立严格约束的时间尺度；(4)确定多年代际、年代际和ENSO时间尺度上的热带大气和气候动力学；(5)评估全新世和末次冰期（LGS）气候和环境变化的区域特征，重点关注亚马逊盆地的变化，并确定它们与其他地区同期条件的比较；(6)为美国国家冰芯实验室提供四分之一的华斯卡兰冰芯存档，以供科学界将来进行调查。潜在的广泛影响包括强大的科学和教育方面。秘鲁安第斯山脉对流层中变暖，加上最近强烈的厄尔尼诺现象，正在加速冰川退缩。目前，这种撤退正在增加旱季的水排放，这是不可持续的。秘鲁的大部分人口生活在西海岸的沙漠地区，这里的农业、水力发电和市政供水都依赖于冰川流。冰川消退也加剧了地质灾害，影响了生态系统、旅游和娱乐。要了解冰川加速流失对未来水资源的影响，需要有关高海拔冰川物质平衡过去变化的信息，除了基于冰芯研究的一些点估计外，这些信息实际上是未知的。决策者、政府机构和公共资源管理者迫切需要这些信息，以帮助指导缓解和适应战略。教育和公众宣传将通过俄亥俄州立大学最近在秘鲁建立的教育和宣传项目进行。这些项目致力于向学生、公众和各级决策者提供气候和环境信息。该项目将支持早期职业科学家，并继续促进科学领域的国际合作。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The researchers intend to drill two 165-meter long cores to bedrock from the col (i.e., the lowest point on a mountain ridge between two peaks) at 6,050 meters above sea level masl) and two 70-meter cores from the South Peak summit at 6,756 masl). Although the col was surveyed and successfully drilled to bedrock in 1993, summit drilling was not possible, and only a few dating techniques were available to help establish a valid time scale for the last 20,000 years. Stable isotope records from Huascaran will provide histories of mid-troposphere temperature and precipitation, and the site's proximity to the Amazon Basin will allow the reconstruction of environmental changes in the vast rainforest by analyzing biological parameters (microbial populations, pollen and methane concentrations).The researchers aim to address the following objectives: (1) document and characterize abrupt climate and environmental variations with emphasis on mid-Holocene events and the deglaciation; (2) assess how the climate and environment have changed over the past century in response to anthropogenic forcing; (3) establish tightly constrained timescales for each of the ice cores; (4) determine tropical atmospheric and climatological dynamics on multi-decadal, decadal, and ENSO time scales; (5) assess the regional characteristics of climatic and environmental variability during the Holocene and Last Glacial Stage (LGS) with a focus on changes in the Amazon Basin and determine how they compare to contemporaneous conditions elsewhere; and (6) provide one-quarter of the Huascaran col core for archival at the U.S. National Ice Core Laboratory for future investigations by the scientific community.The potential Broader Impacts (B.I.) includes strong science and educational aspects. Mid-tropospheric warming in the Peruvian Andes, enhanced by recent strong El Ninos, is accelerating glacier retreat. Currently this retreat is increasing dry season water discharge which is not sustainable. Most of Peru's population lives in the west coast desert which relies on glacier streams for agriculture, hydroelectricity, and municipal water supplies. Retreating glaciers also exacerbate geohazards and impact ecosystems, tourism and recreation. Understanding the impact of this acceleration of glacier loss on future water resources requires information about past changes in high elevation glacier mass balance which is virtually unknown, except from a few point-estimates based on ice core studies. Such information is urgently needed by policymakers, governmental agencies, and public resource administrators to help guide mitigation and adaptation strategies. Educational and public outreach will be conducted through Ohio State University's Education and Outreach Program recently established educational and outreach programs in Peru. Such programs are dedicated to providing climatic and environmental information to students, the public, and policymakers at all levels. The project would support early career scientists and continue to foster international collaborations in science.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.