A Description and Evaluation of an Automated Approach for Feature-Based Tracking of Rossby Wave Packets

AbstractThis paper describes an automated approach to track Rossby wave packets (RWPs), and the sensitivity of various tracking parameters and methods used in filtering the raw data in the feature-based tracking. The NCEP–NCAR reanalysis meridional wind and geopotential height data at 300 hPa every 6 h were spectrally filtered using a Hilbert transform technique under the assumption that RWPs propagate along a waveguide defined by the 14-day running average of the 300-hPa wind. After some spatial and temporal smoothing, the local maxima in RWP amplitude (WPA) were tracked using two objective techniques: a point-based cost optimization routine and a hybrid approach using point identification and object-based tracking following rules. A variation of the total energy flux term of the eddy kinetic energy equation was used to subjectively verify RWP tracks in order to compare the performance of each tracking method. When tracking methods are verified over two winter seasons, the hybrid technique outperformed p...