First meeting of the recently funded second phase of TRR181

Eddies and Internal Waves: Flow Decomposition and Parameterisations

by Manita Choucksey

This meeting is a follow up of the workshop held on 20th November 2018 on ‘Un/Balanced Flow Decomposition Methodologies’ that I organised in Hamburg. This time we further broadened the discussions to bring together the recent advancements in flow decomposition methodologies, wave and eddy parameterizations. The meeting comprised of talks and discussions on the aforementioned topics over three afternoons.

Day 1 of the meeting began with the talk on ‘Inertia-gravitywave scattering by geostrophic turbulence’ by the TRR Mercator fellow Jacques Vanneste, after a welcome and an overview of TRR181 by Carsten Eden and myself. The rest of the afternoon featured talks on waves to tides to multi-scale oceanic motions, wave emission to wave scattering, and laboratory experiments to numerical simulations. A wavy closure to the first day was brought about with the talk on ‘Internal wave generation by tidal currents at super-critical latitudes’ by TRR Mercator fellow Kevin Lamb.

Day 2 of the meeting began with ‘Symmetric instability in crossequatorial western boundary currents’, a joint research work by TRR Mercator fellow David Marshall and Fraser Goldsworth. The 2nd session began with the talk by the speaker of TRR-181, Prof. Carsten Eden on ‘A closure for lee wave drag on the large-scale ocean circulation’. The rest of the afternoon was filled with exciting topics spanning oceanic and atmospheric spectra, near-inertial waves, surface waves, and breaking internal waves. The second day of the meeting came to an energetic closure of with the talk on ‘Ocean transport and eddy energy: Climate Process Team’, by TRR Mercator fellow Laure Zanna.

To add a touch —or rather an illusion— of reality, we as hosts thought of brining some glimpses of Hamburg through pictures during the dramatic winter followed by a dramatic transition to spring, to make up for the the missed opportunities of exploring Hamburg. A group photo of smiling participants brought an end to the second meeting day. The smiles were reassuring that the meeting had been prolific so far, and gave the hint of an excitement to look forward to another day of talks!

Day 3 brought in more shades of eddies and waves: from energy dissipation to wave-vortex interactions, to crossscale energy transfers, including theory, fronts, stirring, and mixing— after a lot of energetic eddies and waves around for the first two days. And thus we concluded the final day of the meeting with exciting talks on fascinating topics and a lot of motivation for science!

Further meeting details, the meeting recording, as well as the book of abstracts can be found at the meeting link: www.trrenergytransfers.de/events/event/ meeting-on-eddies-and-internal waves.

The 3-day TRR-181 Eddy-Wave meeting saw a fantastic set of talks and discussions - many from our enthusiastic friends across the Atlantic who had to be up before the sun did - only for science! We’ve run 3 afternoons of fully virtual meeting on 3 online platforms parallel in 8 time zones(!!), with our friends attending the meeting before sunrise and at some places until shortly before the next sunrise! Still, there were no complaints; instead came the response: ‘It’s better than jet-lag!’

It has been indeed intense but exciting, and an invaluable experience as an organiser (at the same time a participant!)— with so much to learn about organising an event of that scale, along with the technical aspects, as well as ensuring a smooth experience for all! Here, I take the opportunity to thank Stephan Juricke, for the help in setting up and managing the livestream of the meeting and other technical aspects together with me. I thank Prof. Carsten Eden for supporting me to organise this conference, and guiding us all throughout with an ocean of patience for all our questions.

To summarise: 3 days - 3 online platforms - 8 time zones - 15 hours online meeting - 29 talks - 150 participants - and unlimited science! Another aspect to these numbers is the reduction in Carbon footprint (had this been an in-person meeting) which was reduced by ~50 tonnes! The satisfaction of contributing to the health of our planet, however, comes at the cost of missing out on the simple pleasures of life outside the digital world, and consequently the in-person social interaction was heavily missed. Hopefully we will be able to meet in-person in a not-so-distant future!

I hope all the participants had a wonderful meeting experience and a lot of sciencinspiration!

Thank you everyone for being a part of this!

Best wishes and stay healthy, Manita Chouksey