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\begin{document}

\title{Climatology of HF propagation characteristics at very high latitudes
from SuperDARN observations}



\author[1]{Pavlo V. Ponomarenko}%
\author[1]{Kathryn A McWilliams}%
\affil[1]{University of Saskatchewan}%


\vspace{-1em}



  
  \date{May 24, 2024}


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\begin{abstract}
Conventional forecasting of high-frequency (HF, 3-30 MHz) radio wave
propagation is based on a combination of ionospheric and propagation
models. However, at very high latitudes this approach is seriously
undermined by the intrinsically dynamic ionospheric conditions regularly
perturbed by energetic particle precipitations and strong electric
fields. From this perspective, the multi-year observations of HF
propagation characteristics by SuperDARN radars across auroral and polar
cap regions represent a unique opportunity for systematic validation of
the conventional approach, as well as for creating an empirical
propagation model directly from the radar observations. Qualitative
identification and quantitative characterisation of the propagation
modes requires an accurate knowledge of the vertical angle of arrival
(elevation angle) across the high-latitude part of the radar network.
This information has become available only in recent years, facilitated
by the development of reliable data-based calibration techniques for
SuperDARN interferometry. We present the solar-cycle/seasonal/diurnal
climatology of HF propagation characteristics at very high latitudes
derived from two-frequency observations by the Rankin Inlet SuperDARN
radar.%
\end{abstract}%



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