A Comparison of Long-term Meridional Neutral Winds extracted from Arecibo Incoherent Scatter Radar with the Neutral Winds Obtained via Fabry Perot Interferometry

This ten-week summer study compares long term averages of the meridional (north-south) component of neutral winds obtained by Arecibo 630 nm Fabry Perot interferometry (FPI), with those obtained by the Arecibo incoherent scatter radar (ISR). Night-time meridional neutral winds from the ISR were plotted by year and by month for the period between 1985 and 2003, and compared to the plots produced by Robles et al [1], who investigated FPI derived neutral winds. The magnitude and trends of the ISR data fit well with the FPI study, indicating that the neutral wind vector rotated from southeast to due east mostly due to changes in the meridional (north-south) component. A shift in the vector over time is important for modeling the ionosphere, since neutral winds are one of three main forces in the F-region of the ionosphere (region of atmosphere starting at 150 km above the earth's surface) that drive the movement of plasma. The ionosphere is the primary medium of much RF communication, and modeling plasma movement assists in mitigating unwanted propagation effects.