RAPID: Responses of the California Current Ecosystem to El Nino 2015-16

RAPID：加州当前生态系统对厄尔尼诺现象的反应 2015-16

• 批准号: 1614359
• 负责人: Mark Ohman
• 金额: $ 20万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 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: 2016-02-01 至 2018-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1614359&HistoricalAwards=false
• 关键词: RAPID; Responses; California; Current; Ecosystem

The California Current System off the U.S. west coast includes a coastal upwelling region that is among the most productive ocean ecosystems within the U.S. Exclusive Economic Zone, and the world. This upwelling domain extends along the coasts of Washington, Oregon, and California. Many living marine resources develop in this region, which includes five National Marine Sanctuaries. Variability in ocean climate in this region directly and indirectly influences both harvested and protected marine populations, including numerous species of marine fishes, invertebrates, marine mammals, and seabirds. The California Current System is also important to drawdown of atmospheric carbon dioxide and carbon sequestration, due to the high primary productivity of the coastal ocean and processes that transfer carbon and other elements into deep ocean waters. Of sources of climate variability, El Niño is considered the largest climate signal on earth. It markedly influences many ocean populations, as well as modifying weather patterns across the United States. The current El Niño of 2015-16 has been characterized as a "strong" event by the U.S. Climate Prediction Center, and may become one of the strongest El Niños in recent history. In addition, this El Niño follows a sustained, unusual warming in the Northeast Pacific Ocean that began in 2014, and then intensified along the west coast of North America in 2015. The combination of these two ocean perturbations is expected to alter marine ecosystems in many ways. The purpose of the proposed research is to quantify the effects of El Niño on key processes acting on planktonic organisms at the base of the ocean food web, because responses of these organisms are fundamental to understanding and forecasting the effects of El Niño on higher order consumers in the food web. The Broader Impacts of this research include the provision of new quantitative understanding that will be incorporated into future forecast models of the effects of El Niño off the U.S. west coast. This improved understanding will aid in the management of key living marine resources. The research will involve numerous graduate students in at-sea science and aid in the training of the next generation of ocean scientists. The investigators will develop public programs and outreach efforts in collaboration with the Birch Aquarium at Scripps, including an Explore-It: Plankton! public program that will increase public awareness and understanding of El Niño effects on coastal pelagic communities. They will also develop a Science Exploration Adventure (SEA) Days program that will focus on the CCE El Niño response cruise, in order to connect visitors directly to the process of ocean research and careers in the ocean sciences. A RAPID response proposal is necessary because this El Niño will be of limited duration and there is insufficient time to submit a proposal through the regular process.A 20-day research cruise will be conducted in the southern sector of the California Current Ecosystem, a region with an extensive series of baseline measurements against which the effects of El Niño can be compared. We will quantify the effects of El Niño on key rate processes that control the structure of the pelagic food web and control rates of elemental cycling. The processes measured will include primary and secondary production, grazing, dissolved iron effects on phytoplankton growth, carbon and nitrogen recycling, and elemental export in both particulate and dissolved forms. The measurement approach entails a Lagrangian (water parcel-tracking) study of a series of discrete water parcels that represent different subregions: the nearshore coastal upwelling region, the offshore wind-stress curl upwelling domain, the low salinity core flow of the California Current proper, and more stratified ocean conditions offshore. Measurements will be done by in situ incubations at multiple light depths, by simulated in situ incubations aboard ship, and by vertically stratified sampling in each discrete water parcel. These measurements will facilitate the development of quantitative forecast models that can be used to project ocean responses to future El Niños and perhaps other warming phenomena.

美国西海岸的加州海流系统包括一个沿海上升流区域，该区域是美国专属经济区和世界上最具生产力的海洋生态系统之一。 这个上升流区域沿着华盛顿、俄勒冈州和加州的海岸延伸。 许多海洋生物资源在该地区发展，其中包括五个国家海洋保护区。 该区域海洋气候的变化直接和间接地影响到捕捞和保护的海洋种群，包括许多海洋鱼类、无脊椎动物、海洋哺乳动物和海鸟。 加州洋流系统对减少大气中的二氧化碳和碳固存也很重要，因为沿海海洋的初级生产力很高，而且还有将碳和其他元素转移到深海沃茨中的过程。 在气候变化的来源中，厄尔尼诺被认为是地球上最大的气候信号。 它显著地影响了许多海洋种群，并改变了美国各地的天气模式。 2015-16年的厄尔尼诺现象被美国气候预测中心定性为“强”事件，并可能成为近代历史上最强的厄尔尼诺现象之一。 此外，这次厄尔尼诺现象发生在2014年开始的东北太平洋持续异常变暖之后，然后在2015年沿北美西海岸沿着加剧。 预计这两种海洋扰动的结合将在许多方面改变海洋生态系统。 拟议研究的目的是量化厄尔尼诺现象对海洋食物网底层浮游生物的关键作用过程的影响，因为这些生物的反应对于了解和预测厄尔尼诺现象对食物网高级消费者的影响至关重要。 这项研究的更广泛的影响包括提供新的定量理解，这些理解将被纳入美国西海岸厄尔尼诺影响的未来预测模型。 这种更好的了解将有助于管理关键的海洋生物资源。 这项研究将涉及许多海洋科学研究生，并有助于培训下一代海洋科学家。 调查人员将与斯克里普斯的桦树水族馆合作开发公共项目和推广工作，包括探索它：浮游生物！这是一项公共计划，将提高公众对厄尔尼诺现象对沿海远洋社区影响的认识和理解。 他们还将开发一个科学探索冒险（SEA）日计划，重点是CCE厄尔尼诺响应巡航，以便将游客直接连接到海洋研究和海洋科学事业的过程。 由于厄尔尼诺现象持续时间有限，并且没有足够的时间通过常规程序提交提案，因此有必要提出快速应对提案。将在加州洋流生态系统南部进行为期20天的研究巡航，该地区拥有广泛的厄尔尼诺现象。一系列基线测量结果可以与厄尔尼诺现象的影响进行比较。 我们将量化厄尔尼诺对控制远洋食物网结构和控制元素循环速率的关键速率过程的影响。 测量的过程将包括初级和次级生产、放牧、溶解铁对浮游植物生长的影响、碳和氮的再循环以及颗粒和溶解形式的元素输出。 测量方法需要拉格朗日（水包裹跟踪）的一系列离散的水包裹，代表不同的分区：近岸沿海上升流区域，离岸风应力卷曲上升流域，低盐度核心流的加州电流适当的，和更分层的海洋条件离岸的研究。测量将通过在多个光深度的原位培养，船上模拟原位培养，并在每个离散的水包垂直分层取样。这些测量将有助于发展定量预测模型，用于预测海洋对未来厄尔尼诺现象和其他变暖现象的反应。