AbstractAuroral westward flow channels (AWFCs) are intense, narrow channels of westward drift overlapping the equatorward edge of the auroral oval in the pre-magnetic midnight sector. They are a close relative of the sub-auroral polarisation stream which encompasses polarisation jets, a phenomenon also known as sub-auroral ion drift events. Recent observations made with the Tasman Geospace Environment Radar (TIGER) (147.2°E, 43.4°S Geodetic; 55.0° Geomagnetic) have revealed close associations between the appearance of AWFCs and substorm onset, and their subsequent decay toward the end of recovery phase. In fact, in terms of electric field strength, they are the strongest signatures of substorms in the ionospheric convection (>50mVm−1). In terms of electric potential difference (>10kV), they also represent a substantial fraction of the total potential difference generated during substorms. The AWFCs exhibit a diverse range of behaviour, there being no typical event. The radar observations show that radial polarisation fields sometimes oscillate towards and away from the Earth, and bifurcate, within regions of closed flux in the magnetotail throughout substorm evolution. We have identified every AWFC observed by TIGER during the first year of operation, 2000. Simple statistical arguments imply that one, if not more, AWFC probably occurs during every substorm. AWFCs are a fundamental aspect of substorm evolution.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    On the occurrence of auroral westward flow channels and substorm phase


    Contributors:
    Parkinson, M.L. (author) / Dyson, P.L. (author) / Pinnock, M. (author)

    Published in:

    Advances in Space Research ; 38 , 8 ; 1755-1762


    Publication date :

    2005-08-16


    Size :

    8 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English





    On the occurrence of auroral westward flow channels and substorm phase

    Parkinson, M. L. / Dyson, P. L. / Pinnock, M. et al. | British Library Conference Proceedings | 2006


    On the Relationship Between Parameters of Substorm Current Wedge and Westward Electrojet

    Vagina, L. I. / Sergeev, V. A. / Kotikov, A. L. et al. | British Library Conference Proceedings | 1997



    Westward Traveling Surge Dynamics and the Local Structure of an Isolated Substorm

    Lazutin, L. / Starkov, G. / Meng, C.-I. et al. | British Library Conference Proceedings | 2001