A method for tracking individual planetary waves in remotely sensed data

We describe a methodology for tracking individual planetary waves in longitude-time plots of satellite data, based on fitting an elementary wave shape model to subsets of the data by maximum likelihood, then reconstructing the trajectory and evolution of every single wave (where for "single wave" we mean an individual positive or negative westward propagating anomaly) by joining the elementary waves according to their similarity. We then illustrate the potential of the methodology with an example at 34/spl deg/N in the Atlantic Ocean and its adaptability to different cases with a second example on eastward-propagating Kelvin waves in the equatorial Pacific. Although the examples given use sea surface height anomaly data, the technique lends itself to be applied to any space-time plot of any dataset displaying propagation and, in particular, to sea surface temperature data.

[1]  S. Basu,et al.  Eddies in the eastern Gulf of Alaska from TOPEX/POSEIDON altimetry , 1999 .

[2]  P. McCullagh,et al.  Generalized Linear Models , 1992 .

[3]  A. Gordon,et al.  Interannual variability of South Atlantic circulation from 4 years of TOPEX/POSEIDON satellite altimeter observations , 1999 .

[4]  Ananda Pascual,et al.  Mesoscale mapping capabilities of multisatellite altimeter missions: First results with real data in the Mediterranean Sea , 2007 .

[5]  D. Cromwell Sea surface height observations of the 34°N ‘waveguide' in the North Atlantic , 2001 .

[6]  M. Srokosz,et al.  SST Observations of the Agulhas and East Madagascar Retroflections by the TRMM Microwave Imager , 2002 .

[7]  G. Veronis Large Scale Ocean Circulation , 1973 .

[8]  D. Chelton,et al.  Global Observations of Oceanic Rossby Waves , 1996, Science.

[9]  Paolo Cipollini,et al.  Propagation characteristics of extratropical planetary waves observed in the ATSR global sea surface temperature record , 2000 .

[10]  Joaquín Tintoré,et al.  Real-time forecasting at weekly timescales of the SST and SLA of the Ligurian Sea with a satellite-based ocean forecasting (SOFT) system , 2004 .

[11]  R. Pingree,et al.  Westward moving waves or eddies (Storms) on the Subtropical/Azores Front near 32.5°N? Interpretation of the Eulerian currents and temperature records at moorings 155 (35.5°W) and 156 (34.4°W) , 2001 .

[12]  J. Yoder,et al.  Pumping of nutrients to ocean surface waters by the action of propagating planetary waves , 2001, Nature.

[13]  Ii. R.J. Moorhead,et al.  Signal processing aspects of scientific visualization , 1995 .

[14]  R. Stephenson A and V , 1962, The British journal of ophthalmology.

[15]  P. McCullagh,et al.  Generalized Linear Models , 1984 .

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

[17]  D. Chelton,et al.  The Speed of Observed and Theoretical Long Extratropical Planetary Waves , 1997 .

[18]  G. Dibarboure,et al.  Use of a High-Resolution Model to Analyze the Mapping Capabilities of Multiple-Altimeter Missions , 2001 .

[19]  D. Cromwell,et al.  Observations of Rossby wave propagation in the Northeast Atlantic with TOPEX/POSEIDON altimetry , 1998 .

[20]  S. Deans The Radon Transform and Some of Its Applications , 1983 .

[21]  Paolo Cipollini,et al.  Rossby waves detected in global ocean colour data , 2001 .

[22]  Paolo Cipollini,et al.  Use of the 3D radon transform to examine the properties of oceanic Rossby waves , 2001 .

[23]  Paolo Cipollini,et al.  SOFT feature-tracking software handbook , 2003 .