Ocean Mesoscale Eddy Workshop
Ocean Mesoscale Eddy Interactions with the Atmosphere
in conjunction with the 2018 Ocean Sciences Meeting
Several decades of observations have revealed the richness of the mesoscale eddy field in the oceans, especially in association with western boundary currents and the Southern Ocean. These eddies have a strong and readily observable footprint on ocean-surface properties that is conveyed to the atmosphere. Air-sea fluxes are influenced on the eddy scale. And at the same time, there is increasing evidence that ocean eddies have a cumulative effect on air-sea fluxes and can significantly influence the climate of the atmosphere and of the ocean.
The small scales of ocean eddies, however, mean that they are not represented in the current generation global coupled models used for climate prediction and projection (e.g., most CMIP6 simulations will be carried out with models that are not eddy permitting). In short, we have a process — atmosphere-ocean interaction on the ocean eddy scale — that is beginning to be well observed, that is potentially significant for the dynamics and climate of both systems, yet is not captured by our “workhorse” modeling systems. This raises two specific, and related, challenges that will be addressed at the workshop.
How to represent atmospheric feedbacks on ocean eddies in ocean-only models?
How do atmospheric weather and climate respond to the ocean eddy field?
Addressing both challenges requires improved observations and analyses of sea-surface fluxes and developing models that are capable of representing the observed relationships between ocean eddies and fluxes at the sea surface. This workshop addressed the above two challenges in a coordinated way, such that results obtained from different models can be quantitatively compared and evaluated with observational analyses and coupled model outputs.
The overall goal of the workshop was to create a shared understanding of how ocean-atmosphere interactions at the ocean-eddy scale should be represented in climate models to improve climate prediction and projection in both the atmosphere and the ocean.
The workshop brought together the oceanography and atmospheric communities. Meeting participation was limited to ~50 attendees selected through an online application process. A select number of participants presented a poster during the lunch break.
The workshop was structured to include plenary and breakout sessions. There was also a poster session held over lunch on the first day. The first half day was in plenary and comprised of overview presentations, drawing on the 2018 Ocean Sciences Meeting session "Advances in understanding ocean eddies and their interactions with the atmosphere." This was followed by smaller working group discussions, focused on preparing the deliverables. The final half day was in plenary and based on the outcomes from the working group discussions.
Working group 1: Observational requirements for addressing open questions about eddy-scale air-sea fluxes
Outcomes: Shared approaches for diagnosing fluxes from observational data (in situ and remote), possible development of virtual field campaigns
Working group 2: Representation of eddy-scale air-sea fluxes for ocean only models
Outcomes: Protocols for a common modeling activity applying a set of common treatments of fluxes on the mesoscale in different ocean models
Working group 3: Atmospheric weather/climate impacts of the ocean eddy field and its variability
Outcomes: Protocols for two common sets of experiments:
- Applying representations of the ocean eddy field to atmosphere-only models
- Filtering versus retaining ocean eddies in eddy-permitting coupled models
During the breakouts, the three working groups addressed the outcomes identified above. In addition, the organizing committee, in coordination with the working group chairs, will share results with the broader community through a workshop report and articles for Eos, Bulletin of the American Meteorological Society, CLIVAR Exchanges, and/or US CLIVAR Variations.
Scientific Organizing Committee
Ping Chang, Texas A&M University
Eric Chassignet, Florida State University
Walt Robinson, North Carolina State University
Sabrina Speich, Ecole Normale Supérieure
Program Organizing Committee
Jing Li (International CLIVAR)
Mike Patterson (US CLIVAR)
Jill Reisdorf (UCAR)
Kristan Uhlenbrock (US CLIVAR)