Fig. 5

Doppler-shifted velocity components measured by the radar as a function of horizontal displacement at 90 km range, for a transmitter at x = 350 km and a receiver at x = 650 km. The speeds are normalized by division by the true horizontal velocity, so approach unity at the edges. The radar-measured parameter is referred to as v_rad, by analogy with the backscatter case, but it is not truly a radial velocity. Lines are drawn horizontally near the zero-point on the abscissa—values within these lines will have measured speeds less than 0.05 of times the true horizontal speed, making inversion of the data difficult and potentially unreliable