AESOP: Assessing the Effects of Submesoscale Ocean Parameterizations

1. AESOP: Assessing the Effects of Submesoscale Ocean Parameterizations Program Overview Scott Harper Code 322, Physical Oceanography Office of Naval Research harpers@onr.navy.mil

2. AESOP: A Departmental Research Initiative AESOP is a Code 32 “DRI” (all ONR money) • Programs within Code 32 pitch new DRI topics to management during an annual competition (the programs are taxed to provide the funding pool) • Typically three new topics are chosen each year • Represent a 6.1 (Basic Research) investment in a topic area of recognized naval interest • Recent initiatives have been of O(5 years) and O($7 mil) • Goal is to support focused efforts to make progress in difficult or emerging scientific areas

3. AESOP: Program Goals Primary goal: define new methods and metrics to assess the submesoscale parameterizations used in basin and coastal ocean models, specifically with respect to their impact on synoptic model predictions (For our purposes: sub-mesoscale ~ 100 m to 10 km) The focus is on the actual representation and evolution of the ocean state in short-term (one week) model predictions, to determine how well the numerical parameterizations are capturing the unresolved physics in real time. (Somewhat similar NSF’s ‘CPT’s, but for the real ocean)

4. AESOP: Formal Project Participants Observations Mike Gregg (APL/UW) Eric D’Asaro (APL/UW) James Girton (APL/UW) Shaun Johnston (Scripps) Jody Klymak (Scripps) Eric Kunze (UVic) Craig Lee (UW/APL) Rob Pinkel (Scripps) Dan Rudnick (Scripps) Modeling Jim McWilliams (UCLA) Enrique Curchister (LDEO/Columbia) Raffaele Ferrari (MIT) Oliver Fringer (Stanford) Ramsey Harcourt (APL/UW) Rich Hodur / Jim Doyle (NRL-MRY) Alexey Kaplan (LDEO/Columbia) Bill Large (NCAR) John Marshall (MIT) Jennifer MacKinnon (Scripps) Sutanu Sarkar (UCSD) Bob Street (Stanford)

5. AESOP: Schedule Initial Kickoff Meeting, March 8-9, 2005 APL/UW, Seattle, WA Field experiment: Monterey Bay area, August 2006

6. AESOP: Preliminary Observational Plans Mike Gregg / Jack Miller Explore and map diapycnal mixing, likely enhanced in this region by the interactions between the bathymetry and internal waves and tidal currents A 14-day cruise is planned with: • ship-mounted acoustic backscattering system • bottom-mounted ADCPs • towed microstructure profilers

7. AESOP: Preliminary Observational Plans Jody Klymak / Rob Pinkel Quantify the strength of the internal tide, rate of energy conversion to smaller scales, and energy pathways and rates of the dissipation mechanisms R/P FLIP will be moored for one month near the 1500m isobath (the generation site for the on-shore internal tide), equipped with two Doppler sonars and two rapidly profiling CTD’s

8. AESOP: Preliminary Observational Plans Shaun Johnston / Dan Rudnick Provide hydrography and microstructure measurements of the upper 400m at 3km/6m resolution, and current profiles down to 600m at 6-20m resolution R/V Roger Revelle will be requested for a one month cruise, towing a SeaSoar with CTD, fluorometer, and transmissometer

9. AESOP: Preliminary Observational Plans James Girton / Eric Kunze Examine the IW energy and momentum fluxes on the continental slope (500m-2000m), the energy transfer to higher wave numbers, and structure of the bottom boundary layer Ship time required for the XCP and and vertical microstructure surveys extending from the shelf out across the shelf break.

10. AESOP: Preliminary Observational Plans Eric D’Asaro / Craig Lee Examine the horizontal and vertical mixing in regions of strong lateral variability (where the dynamics are truly three dimensional) A combined program of three neutrally buoyant Lagrangian drifters deployed in a region of large horizontal gradients, with a towed Triaxus survey constantly crossing over the location of the drifters for several days

11. AESOP: Preliminary Modeling Plans Jim McWilliams / Bob Street / Oliver Fringer Nesting of non-hydrostatic SUNTANS code within the ROMS framework, to address the non-hydrostatic effects of the IW and internal tide generation and dissipation on the shelf (in conjunction with the NLIWI DRI) Sutanu Sarkar Comparison and coupling of ROMS with Fine Resolution LES code (FRLES), using momentum and buoyancy fluxes to compare against the collected observational data set

12. AESOP: Preliminary Modeling Plans John Marshall / Raf Ferrari Exploring the super-parameterization technique in the non-hydrostatic MITgcm code Alexey Kaplan / Bill Large Enrique Curchister Running ROMS model at different resolutions and filtering the contribution of various mixing parameterizations to explore the impact of resolution

13. AESOP: Preliminary Modeling Plans Jen MacKinnon LES modeling to explore wave-wave interactions on the shelf, to guide the observational program and provide additional insight into energy conversion Ramsey Harcourt Running LES models of regions with large lateral gradients, using the Lagrangian and Triaxus observations of D’Asaro and Lee, to determine if the budgets can be closed locally

14. AESOP: Project Summary • Some products we hope to generate: • new methods for assessing parameterizations • new knowledge about submesoscale ocean processes • a data set of sufficient temporal and spatial resolution to be used for future parameterization studies • insight into the relative importance of different processes at various resolutions • information on how current parameterizations affect ocean predictions • new metrics to evaluate ocean models and their predictions

15. Logistics Summary AESOP will try to work with all programs to share whatever data can be provided in real-time Need to coordinate with ASAP to get the ocean forecasts (required for the Lagrangian float deployment and Triaxus survey), and with all projects operating in the region to gather observations for use in hindcasts and diagnostics There are going to be a lot of assets in the water, and coordination will be required for the UNOLS requests (the AWACS/SWA06 experiment is taking place on the east coast at roughly the same time)