Ajayi, A., Le Sommer, J., Chassignet, E., Molines, J. - M., Xu, X., Albert, A., et al. (2020). Spatial and Temporal Variability of the North Atlantic Eddy Field From Two Kilometric-Resolution Ocean Models.
J. Geophys. Res. Oceans, 125(5).
Abstract: Ocean circulation is dominated by turbulent geostrophic eddy fields with typical scales ranging from 10 to 300 km. At mesoscales (>50 km), the size of eddy structures varies regionally following the Rossby radius of deformation. The variability of the scale of smaller eddies is not well known due to the limitations in existing numerical simulations and satellite capability. Nevertheless, it is well established that oceanic flows (<50 km) generally exhibit strong seasonality. In this study, we present a basin‐scale analysis of coherent structures down to 10 km in the North Atlantic Ocean using two submesoscale‐permitting ocean models, a NEMO‐based North Atlantic simulation with a horizontal resolution of 1/60 (NATL60) and an HYCOM‐based Atlantic simulation with a horizontal resolution of 1/50 (HYCOM50). We investigate the spatial and temporal variability of the scale of eddy structures with a particular focus on eddies with scales of 10 to 100 km, and examine the impact of the seasonality of submesoscale energy on the seasonality and distribution of coherent structures in the North Atlantic. Our results show an overall good agreement between the two models in terms of surface wave number spectra and seasonal variability. The key findings of the paper are that (i) the mean size of ocean eddies show strong seasonality; (ii) this seasonality is associated with an increased population of submesoscale eddies (10�50 km) in winter; and (iii) the net release of available potential energy associated with mixed layer instability is responsible for the emergence of the increased population of submesoscale eddies in wintertime.
Arbic, B. K., Shriver, J. F., Hogan, P. J., Hurlburt, H. E., McClean, J. L., Metzger, E. J., et al. (2009). Estimates of bottom flows and bottom boundary layer dissipation of the oceanic general circulation from global high-resolution models.
J. Geophys. Res., 114(C2).
Aretxabaleta, A., Blanton, B. O., Seim, H. E., Werner, F. E., Nelson, J. R., & Chassignet, E. P. (2007). Cold event in the South Atlantic Bight during summer of 2003: Model simulations and implications.
J. Geophys. Res., 112(C5).
Basu, S., Meyers, S. D., & O'Brien, J. J. (2000). Annual and interannual sea level variations in the Indian Ocean from TOPEX/Poseidon observations and ocean model simulations.
J. Geophys. Res., 105(C1), 975–994.
Boisserie, M., Shin, D. W., LaRow, T. E., & Cocke, S. (2006). Evaluation of soil moisture in the Florida State University climate model-National Center for Atmospheric Research community land model (FSU-CLM) using two reanalyses (R2 and ERA40) and in situ observations.
J. Geophys. Res., 111(D8).
Bourassa, M. A. (2000). Shear stress model for the aqueous boundary layer near the air-sea interface.
Journal of Geophysical Research – Oceans, 105(C1), 1167–1176.
Bourassa, M. A., Legler, D. M., O'Brien, J. J., & Smith, S. R. (2003). SeaWinds validation with research vessels.
J. Geophys. Res., 108(C2).
Bourassa, M. A., Zamudio, L., & O'Brien, J. J. (1999). Noninertial flow in NSCAT observations of Tehuantepec winds.
J. Geophys. Res., 104(C5), 11311–11319.
Bozec, A., Lozier, M. S., Chassignet, E. P., & Halliwell, G. R. (2011). On the variability of the Mediterranean Outflow Water in the North Atlantic from 1948 to 2006.
J. Geophys. Res., 116(C9).
Brunke, M. A., Zeng, X., Misra, V., & Beljaars, A. (2008). Integration of a prognostic sea surface skin temperature scheme into weather and climate models.
J. Geophys. Res., 113(D21).