RAPID: Characterizing the Chemical and Physical Signature of the 2015-16 El Nino in the Quelccaya Ice Cap Snow and Ice to Calibrate Past ENSO Reconstructions

RAPID：描述 2015-16 厄尔尼诺现象在奎尔卡亚冰盖冰雪中的化学和物理特征，以校准过去的 ENSO 重建

• 批准号: 1603377
• 负责人: Lonnie Thompson
• 金额: $ 9.63万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-12-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1603377&HistoricalAwards=false
• 关键词: RAPID; Characterizing; Chemical; Physical; Signature

This award uses funds, under the auspices of the Rapid Response Research (RAPID) concept, to dig three new snow pits and collect two new ten-meter long cores from the Quelccaya ice cap (QIC) in southern Peru. Samples from these pits and cores will be physically and chemically analyzed to address the hypotheses that post-depositional features (e.g., melt features) and elevated concentrations of dry deposited trace species (e.g., black carbon, dust, ammonium) provide new and reliable markers of past El Niño-Southern Oscillation (ENSO) events and also help facilitate the quantification of the event's intensity. These new markers will be also applied to other ice cores from the southern Andes that exist from extended tropical ice core archives collected over the last forty years.The chemical and physical fingerprints of past El Niño events are preserved in ice cores from Andean glaciers, particularly the QIC, and offer the potential to quantify past regional ENSO variability. Previous isotopic (delta 18-Oxygen) records from the QIC provided a long annually resolved history (1,800 years) of Pacific sea surface temperature (SST) variations. However, delta 18-O on the QIC is also influenced by other internally varying climate system processes (e.g., South American Monsoon, ITCZ position). Consequently, additional El Niño proxies are needed to reduce the uncertainties inherent in past El Niño reconstructions and to help facilitate more accurate projections of intensity and frequency.The new data that could result from the research is aimed at testing two hypotheses: 1) the snow melt and percolation induced by El Niño is identifiable in the prior year's snow layer and can be calibrated to the El Niño's strength in terms of temperature and radiative forcing; and 2) the concentration and co-association of biogenic and evaporitic species will be enhanced and detectable deeper in the ice and thereby reveal past El Niño frequency.The potential broader impacts include capturing the chemical and physical signatures of a modern El Niño event in real time that could help evaluate past ENSO variability preserved in ice cores as well as assessing the role of solar forcing in climate. The research will help support an early career female scientist and the research results will be disseminated in short video segments appropriate for the public.

该奖项利用快速响应研究 (RAPID) 概念的资助，挖掘三个新的雪坑，并从秘鲁南部的奎尔卡亚冰盖 (QIC) 收集两个新的十米长的冰芯和样本。将对岩心进行物理和化学分析，以解决沉积后特征（例如熔化特征）和干沉积痕量物质（例如黑碳、灰尘、铵）浓度升高所提供的假设过去厄尔尼诺-南方涛动（ENSO）事件的新的、可靠的标记，也有助于促进该事件强度的量化。这些新的标记也将应用于从扩展的热带冰芯档案中收集的来自安第斯山脉南部的其他冰芯。过去四十年。过去厄尔尼诺事件的化学和物理指纹保存在安第斯冰川的冰芯中，特别是 QIC，并提供了量化过去区域 ENSO 变化的潜力。 QIC 的 (delta 18-Oxygen) 记录提供了太平洋海面温度 (SST) 变化的长期年度解析历史（1,800 年），但是，QIC 上的 delta 18-O 也受到其他内部变化的气候系统过程的影响。例如，南美季风、ITCZ 位置），需要额外的厄尔尼诺代理来减少过去厄尔尼诺重建中固有的不确定性，并帮助促进更准确的强度预测。该研究可能产生的新数据旨在检验两个假设：1）厄尔尼诺现象引起的雪融化和渗透可以在前一年的雪层中识别出来，并且可以根据厄尔尼诺现象的强度进行校准温度和辐射强迫；2) 生物和蒸发物种的浓度和共同关联将在冰层深处增强和检测，从而揭示过去的厄尔尼诺现象频率。潜在的更广泛的影响包括捕获化学物质和蒸发物质。现代厄尔尼诺事件的实时物理特征，可以帮助评估冰芯中保存的过去的 ENSO 变化，以及评估太阳强迫在气候中的作用。这项研究将有助于支持早期职业女性科学家，研究结果将是以适合公众的短视频片段传播。