Using data from the Super Dual Auroral Radar Network (SuperDARN) we investigatethe ionospheric convection response to magnetospheric substorms. Substormswere identified using the Far Ultraviolet (FUV) instrument on board theImager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft, andwere then binned according to the magnetic latitude of their onset. Asuperposed epoch analysis of the ionospheric convection patterns for eachonset-latitude bin was then performed using radar data for the interval 60 minbefore onset to 90 min after. It is found that loweronset-latitude substorms are associated with generally more enhancedconvection than the higher latitude substorms, although they suffer from asignificant localised reduction of the flow in the midnight sector during theexpansion phase. Higher-latitude substorms are associated with a significantand rapid increase in the nightside convection following substorm onset, withall onset-latitude bins showing an enhancement over onset values by ~60 mininto the expansion phase. A rudimentary inspection of the concurrentauroral evolution suggests that the duration of the flow reduction followingsubstorm onset is dependent on the strength and duration of the expansionphase aurora and its associated conductivity enhancement.
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