Can oceanic submesoscale processes be observed with satellite altimetry?

High-resolution (2 km and hourly) observations of surface currents from High-Frequency Radars are analyzed in terms of sea level anomalies (SLA) and compared with data from two satellite altimeter ground tracks. Purpose is to investigate whether ocean submesoscale processes can be observed with satellite altimetry. Our results highlight two major problems that must be overcome before being able to resolve submesoscale processes with altimetry: (i) signal contamination from high-frequency motions and in particular from incoherent internal tides (near-inertial oscillations have no effect on SLA), and (ii) measurement noise which prevents the computation of accurate cross-track currents on scales O (10 km). The latter may be overcome by future satellite altimeter missions, but the former will require taking into account the effect of mesoscale variability on internal tide propagation in regions where internal tides are significant. Citation: Chavanne, C. P., and P. Klein (2010), Can oceanic submesoscale processes be observed with satellite altimetry?, Geophys. Res. Lett., 37, L22602, doi: 10.1029/2010GL045057.

[1]  K. Gurgel,et al.  The Surface Expression of Semidiurnal Internal Tides near a Strong Source at Hawaii. Part I: Observations and Numerical Predictions* , 2010 .

[2]  J. McWilliams,et al.  Mesoscale to Submesoscale Transition in the California Current System. Part I: Flow Structure, Eddy Flux, and Observational Tests , 2008 .

[3]  Gilles Reverdin,et al.  Global high-resolution mapping of ocean circulation from TOPEX/Poseidon and ERS-1 and -2 , 2000 .

[4]  Lee-Lueng Fu,et al.  Observing Oceanic Submesoscale Processes From Space , 2008 .

[5]  K. Gurgel,et al.  Observations of Vortex Rossby Waves Associated with a Mesoscale Cyclone , 2010 .

[6]  D. Chelton,et al.  Global observations of large oceanic eddies , 2007 .

[7]  K. Gurgel,et al.  Interactions between a Submesoscale Anticyclonic Vortex and a Front , 2010 .

[8]  G. Mitchum,et al.  Surface manifestation of internal tides generated near Hawaii , 1996 .

[9]  Patrice Klein,et al.  Upper Ocean Turbulence from High-Resolution 3D Simulations , 2008 .

[10]  E. Joseph Metzger,et al.  Concurrent Simulation of the Eddying General Circulation and Tides in a Global Ocean Model , 2010 .

[11]  Bertrand Chapron,et al.  Diagnosis of vertical velocities in the upper ocean from high resolution sea surface height , 2009 .

[12]  K. Gurgel,et al.  The Surface Expression of Semidiurnal Internal Tides near a Strong Source at Hawaii. Part II: Interactions with Mesoscale Currents* , 2010 .

[13]  Patrice Klein,et al.  Wind ringing of the ocean in presence of mesoscale eddies , 2004 .