RAPID: Galapagos lake chemistry and plankton assemblage during the 2015-16 El Nino

RAPID：2015-16 厄尔尼诺期间加拉帕戈斯湖化学和浮游生物组合

• 批准号: 1608241
• 负责人: Julian Sachs
• 金额: $ 7.5万
• 依托单位: University of Washington
• 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: 2015-12-15 至 2017-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608241&HistoricalAwards=false
• 关键词: RAPID; Galapagos; lake; chemistry; plankton

Robust reconstructions of tropical Pacific climate are critically important for understanding past climate change due to the unique ability of this region to influence climate on a global scale. The El Niño-Southern Oscillation (ENSO) affects precipitation and temperature patterns across more than half of the globe every 3-7 years. Impacts associated with ENSO include drought, flooding, crop failure, disease, and changes in ocean productivity. Importantly, large uncertainties exist regarding how ENSO has changed in the past and how it is likely to change in a higher CO2 world. Improving ENSO reconstructions from the vastly under-sampled eastern equatorial Pacific will help elucidate the response of ENSO to large-scale changes in the climate system and thus poses tremendous benefit to society. Freshwater and coastal saline lake sediments in the Galápagos Islands provide invaluable long continuous reconstructions of rainfall from the eastern equatorial Pacific, where annual rainfall is strongly correlated to El Niño sea surface temperatures. To date, however, such reconstructions have been hampered by large uncertainties owing to the lack of direct measurements of the response of Galápagos lakes to El Niño conditions.This project seeks to leverage the 2015-2016 strong El Niño event that is currently underway to improve constraints on these and future rainfall reconstructions from the tropical Pacific. Towards this end, a comprehensive set of meteorological and lake measurements will be taken at El Junco Lake (San Cristobal Island) and Poza del Diablo and Poza Verde (Isabela Island) during the onset, peak, and decay phase of the El Niño event in collaboration with Equadorian scientists and the Charles Darwin Research Station. Measurements will include hydrologic fluxes (precipitation, evaporation) and their isotopic composition (d2Hrain), as well as physical, chemical, and biological properties of the lakes (d2Hlake, temperature, salinity, nutrients, pH, phytoplankton assemblage, depth, and d2H of plant and algal biomarkers). These data will enable the relationship between modern climate and the paleoclimate proxies to be explicitly evaluated through the course of a rare strong El Niño event (the last of which occurred 18 years ago). This dataset would be the most comprehensive characterization of the influence of El Niño events on these lake systems to date and would greatly advance ongoing efforts to construct quantitative paleo-ENSO records from this region. The work is supported by Marine Geology and Geophysics, Earth Sciences Global Change, and the Office of International Science and Engineering.

热带太平洋气候的强大重建对于理解过去的气候变化至关重要，因为该地区在全球范围内影响气候的独特能力。厄尔尼诺 - 南方振荡（ENSO）每3 - 7年都会影响全球一半以上的降水和温度模式。与ENSO相关的影响包括干旱，洪水，作物衰竭，疾病以及海洋生产力的变化。重要的是，关于ENSO过去的变化以及在更高的二氧化碳世界中可能如何变化的大型不确定性存在。改进了来自大量不足的东部赤道太平洋的ENSO重建将有助于阐明ENSO对气候系统大规模变化的反应，从而对社会造成巨大好处。加拉帕戈斯群岛的淡水和沿海盐湖沉积物提供了来自东部等效太平洋降雨的宝贵持续重建，在那里，年度降雨与厄尔尼诺海洋表面温度密切相关。然而，迄今为止，由于缺乏对Galápagos湖对ElNiño条件的响应的直接测量，因此这类重建受到了严重的不确定性的阻碍。该项目旨在利用2015 - 2016年强大的ElNiño事件，目前正在进行对这些和未来对这些Tropical Pactruction的限制的约束。为此，将在ElNiño事件的发作，高峰和衰败阶段在与Equatorian Scientist和Charles Darwin Research Station合作的El Junco Lake（San Cristobal Island）以及Poza del Diablo和Poza diablo和Poza Verde（Isabela Island）中进行全面的气象和湖泊测量。测量将包括水文通量（降水，蒸发）及其同位素组成（D2HRAIN），以及湖泊的物理，化学和生物学特性（D2HLAKE，D2HLAKE，温度，盐度，盐度，营养素，pH，PH，Phytoplankton phytoplankton组合，深度，深度，以及植物和Algal anggal Biomarkarsers）。这些数据将使现代气候和古气候代理之间的关系能够通过罕见的强大厄尔尼诺事件（18年前发生）明确评估。迄今为止，数据集将是厄尔尼诺事件对这些湖泊系统的影响的最全面的表征，并将大大促进持续的努力来构建该地区的定量古enso记录。这项工作得到了海洋地质与地球物理学，地球科学全球变化以及国际科学与工程办公室的支持。