HR: 0800h
AN: SM31A-0391    [Abstracts]
TI: Coupling Between Cross Polar Cap Potential (CPCP) and Lower Auroral Electroject (AL)
AU: * Redmon, R
EM: Rob.Redmon@noaa.gov
AF: NOAA / NGDC, 325 Broadway St. E/GC2, Boulder, CO 80305 United States
AU: Zhizhin, M
EM: jjn@wdcb.ru
AF: Geophysical Center, Russian Academy of Sciences, 3 Molodezhnaya Str., Moscow, 117296 Russian Federation
AU: Kihn, E
EM: Eric.A.Kihn@noaa.gov
AF: NOAA / NGDC, 325 Broadway St. E/GC2, Boulder, CO 80305 United States
AB: We investigate coupling and synchronization between substorm onset and convection enhancement in the high latitude ionosphere during substorm events. It is known that the global auroral electrojet (AE) indices, more specifically auroral electrojet lower (AL), is an indicator of electrojet current intensity which is the most significant substorm input leading to convection enhancement in the auroral region during substorm events. Cross polar cap potential (CPCP) is also a well established indicator of high latitude convection strength. While the long term time averages (i.e. hours) of AL and CPCP are quasi linearly correlated, the same cannot be said of shorter time scales (i.e. minutes), specifically for substorms occurring after long quiet times, i.e. low convection enhancement. During such substorms, AL and CPCP do not show signs of strong linear correlation. It has been proposed that there exists a nonlinear coupling as well as synchronization between AL and CPCP at these shorter time scales. We present various measures of correlation and synchronization including time delay estimates and synchronization likelihood to characterize the coupling between AL and CPCP. These results have utility in segregating and timing of disturbances caused by enhanced convection and substorm expansion.
DE: 2475 Polar cap ionosphere
DE: 7900 SPACE WEATHER
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005