With D. Cherian, R. Holmes, S. Bachman, RC. Lien and W. Large
Due to the far-reaching societal impacts, developing models and observing systems that enable reliable forecasts of the tropical Pacific Ocean in general and the Equatorial Cold Tongue (ECT) in particular are a high priority. However, global numerical models used for this purpose have significant deficiencies. Several of these deficiencies may result from poorly-constrained parameterizations in the ocean model and/or coarse grid resolution (usually 10-100 km in the horizontal and 10 m in the vertical). For example, upwelling and vertical mixing are two processes that are crucial components of the heat budget of the ECT, but these processes have traditionally been difficult to observe and depend significantly on physics that occurs at scales much smaller than a typical model grid cell. In addition, previous studies have demonstrated that these processes are sensitive to model resolution and parameterization scheme. This collaborative project includes a team of modelers and observationalists conducting and analyzing process-oriented numerical experiments designed to reveal how small-scale (below 500 km, subannual) processes contribute to upwelling, mixing and thereby the heat budget of the ECT, a “pacemaker” of global climate. Scales from about 500 km to 1 km will be addressed with high-resolution, nested simulations in a regional ocean model and scales from about 1 km to 1 m will be addressed with turbulence-resolving large eddy simulations (LES).
Cherian, D., D.B. Whitt, R. M. Holmes, R.C. Lien, S. Bachman, W. G. Large, (2020). Off-equatorial deep cycle turbulence forced by Tropical Instability Waves in the equatorial Pacific. J. Phys. Oceanogr. [doi]
Whitt, D.B., D. Cherian, R. M. Holmes, S. Bachman, R-C. Lien, W. G. Large, J. N. Moum (2021). Simulation and scaling of the vertical heat transport in deep-cycle turbulence throughout the equatorial Pacific cold tongue