Ocean Gateways and Choke Points: Progress and Challenges

全球海洋环流以各种方式影响我们的气候，并在协调地球对气候变化的反应方面发挥核心作用。这种环流的一个关键方面是控制环流的强度、结构和盆地连通性的特定局部门户(或阻塞点)的重要性。这种门户的例子有印度尼西亚的Throughflow，Agulhas Retroflect，以及罗斯海和韦德尔海的流出等等。这些系统通常由多个强喷流组成，这些喷流在一定的空间和时间尺度上变化不同，因此对其进行观测、建模和预测仍然具有极大的挑战性。阿诺德·戈登教授独特的研究生涯跨越了50多年，改变了我们对海洋门户及其在气候、生物地球化学和生态系统中的作用的理解。鉴于新的观测技术的迅速发展，以及对了解气候变化加速速度至关重要的一类新的高分辨率全球海洋模型的出现，评估海洋门户领域的知识状况并确定未来研究的关键挑战的时机已经成熟。这次为期两天的研讨会汇集了来自世界各地的杰出和职业早期研究人员，包括观察家、理论家和模型师，以解决这些主题。研讨会将于2020年2月在圣地亚哥的斯克里普斯海洋研究所举行，恰逢阿诺德·戈登的80岁生日，并将在2020年海洋科学会议的前一周举行，以最大限度地减少旅行所花费的时间和金钱。这笔赠款将支持15名早期职业研究人员的参与，他们将接触到海洋门户领域的机遇和挑战。除出席专题讨论会的人员外，还将利用广泛的网上外联，以确保有广泛、多样化的与会者。结果将通过EOS上的一篇文章分享，并纳入各种国家和国际科学议程。像《逃离德黑兰》这样的当代全球海洋观测计划并没有对海洋门户进行足够的空间和时间细节采样，以揭示它们的物理原理。监测这些门户需要专门的、专门的观测活动和持续的系泊天文台。关于这些通道在气候时间尺度上的路径、结构和可变性的许多基本问题仍然没有答案。至关重要的是，从过去获得的关于如何成功收集这些观测数据的知识要传给下一代海洋学家，以保持早期研究的动力并推进新的观测技术。传统上，数值模型很难真实地表示海洋门户，但计算能力和数值技术的进步最近导致了重大改进。将观测和建模社区聚集在一个研讨会上将促进快速进步，并为识别系统中的知识差距提供一个独特的论坛，从而为未来的门户观测系统建立更好的综合战略。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The global ocean circulation affects our climate in myriad ways and plays a central role in mediating the planet's response to climate change. A key aspect of this circulation is the importance of specific localized gateways (or choke points) which control the strength, structure and basin connectivity of the circulation. Examples of such gateways are the Indonesian Throughflow, the Agulhas retroflection, and outflows from the Ross and Weddell Seas to name a few. These systems often consist of multiple strong jets that vary over a range of space and time scales and so remain extremely challenging to observe, model and predict. Professor Arnold Gordon's singular research career, spanning over 50 years, has transformed our understanding of ocean gateways and their role in climate, biogeochemistry and ecosystems. Given the rapid development of new observing technologies, and the emergence of a new class of high-resolution global ocean models that are critical for understanding the accelerating rate of climate change, the time is ripe to assess the state of knowledge in the field of ocean gateways and define key challenges for future research. This two-day workshop to bring together distinguished and early-career researchers from across the world, including observationalists, theoreticians and modellers to address these topics. The workshop, to be held at Scripps Institution of Oceanography in San Diego in February 2020, will coincide with Arnold Gordon's 80th birthday and occur in the week prior to the 2020 Ocean Science meeting to minimize time and money spent on travel. This grant will support the participation of 15 early career researchers, who will gain exposure to the opportunities and challenges in the field of ocean gateways. Extensive web-based outreach will be used to ensure a broad, diverse pool of participants in addition to those present at the symposium. Results will be shared via an article in EOS and incorporated in the various national and international science agendas. Contemporary global ocean observing programs like Argo do not sample ocean gateways with sufficient spatial and temporal detail to uncover their physics. Monitoring these gateways requires specialized, dedicated observational campaigns and sustained moored observatories. Many fundamental questions about the pathways, structure and variability of these gateways on climate time scales remain unanswered. It is crucial that the knowledge garnered from the past of how to successfully collect these observations is passed on to the next generation of oceanographers, to maintain the impetus from earlier studies and to advance new observing technology. Numerical models have traditionally struggled to realistically represent ocean gateways, but advances in computational power and numerical techniques have recently led to major improvements. Bringing together the observational and modeling communities at a single workshop will catalyze rapid progress and provide a unique forum for identifying knowledge gaps in the system so as to build a better integrated strategy for a gateway observing system of the future.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.