Jun 13 – 19, 2015
University of Alberta
America/Edmonton timezone
Welcome to the 2015 CAP Congress! / Bienvenue au congrès de l'ACP 2015!

Dawn-dusk asymmetry in the intensity of polar cap flows as seen by SuperDARN

Jun 16, 2015, 3:00 PM
CAB 243 (University of Alberta)

CAB 243

University of Alberta

Oral (Non-Student) / orale (non-étudiant) Atmospheric and Space Physics / Physique atmosphérique et de l'espace (DASP-DPAE) T2-3 Ground-based / in situ observations and studies of space environment II (DASP) / Observations et études de l'environnement spatial, sur terre et in situ II (DPAE)


Alexandre Koustov (U)


Polar cap flow pattern and intensity depend on the IMF Bz and By components. For IMF Bz<0, the pattern is consistently two-celled, and previous studies indicate that flows are fastest near noon and midnight for By<0 and during afternoon-dusk hours for By>0. In this study, we investigate the polar cap flow intensity in two ways. First we consider highly-averaged (over each month of observations in 2007-2013) convection patterns inferred from all SuperDARN radar measurements and discuss typical configurations of the polar cap region with enhanced flows, depending on the IMF By, with a focus on the dusk-dawn asymmetry. We demonstrate seasonal and perhaps solar cycle changes in the asymmetry. We then consider 2 years of Clyde River radar data on the azimuthal component of the flow and show the asymmetry observed directly. We discuss the complexity of the phenomenon in contrast to the more firm conclusions of previous studies.

Primary author


Dr Robyn Fiori (NRcan) Ms Zahra Abooali zadeh (U of Saskatchewan)

Presentation materials