Automated processing system for tidal analysis of MF radar winds

Abstract

The medium frequency (MF) radar at Platteville, Colorado (40.18° N, 104.7° W) is used to estimate the zonal and meridional wind motions in the middle atmosphere. This radar has been in operation since January 2000. We currently have four years of wind estimates sampled every five minutes. An automated processing system has been developed in IDL to process these estimates and obtain the monthly mean winds and tidal parameters. The automated processing currently processes the wind estimates in time domain analysis using a least square fitting technique. The criteria for determining when the estimated tidal parameters are valid have been studied along with the error analysis of the data and processing. The diurnal and semidiurnal parameters are obtained using this least square fitting method and these tidal parameters are assumed to be valid only when the condition number is less than 10. In the spectral domain, the fast Fourier transform and Lomb-Scargle periodogram methods have been studied. A test signal is generated and its performance using both FFT and Lomb-Scargle methods are discussed for three different cases which are equivalent to our actual data. The results of the wind estimates from 2000-2003 collected using the MF radar have been processed using the automated processing system. This automated processing system can be used to generate the wind parameters on a 24 hour, 7 day a week basis for an elaborate study. Our data are compared with MF radar data from Saskatoon, Canada and Urbana, lllinois. Most of the time our data are similar to the behavior of GSWM-02 model.