The structure of current system for polar substorm
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The Structure of Current System for Polar Substorm. A.Kotikov, Saint-Petersburg University A.Zaitsev, IZMIRAN, e-mail:

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The Structure of Current System for Polar Substorm

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The Structure of Current Systemfor Polar Substorm

A.Kotikov, Saint-Petersburg University

A.Zaitsev, IZMIRAN, e-mail:

Statistical current system based on IGY data – main sources are westward and eastward electrojets and currents in polar cap. A –convective, B – explosive,C – polar cap currentsD - complex current system


Y.Feldstein, A.Zaitsev,

Sd-variation of the magnetic field in high latitudes with different intensity of magnetic disturbances,

Annales Geoph.,v.24, n.2, pp.1-8, 1968

Eastward Electrojet : Facts and Rumors

Rumors: eastward electrojet does not exist as own source,

does not play a significant role in substorm

Facts: eastward electrojet is the essential source of polar . geomagnetic disturbances on his own,

two types of eastward electrojets are observed

Convective Explosive

Positioned around 15-18 LT positioned around 21-00 LT

Spread current sheet Distinctive jet-like current

Strong seasonal dependence No seasonal dependence

Have not accompany by riometer Accompanied by riometer absorption

Have not pronounced conjugacy Clear conjugate

Not display Harang discontinuity To form the Harang discontinuity

Have a connection with magnetosphere Have a connection with the partial

convection cell ? ring current ?

Extra strong eastward electrojet

Magnetic Superstorm at Jan.11, 1997Cape Kamenny, Yamal, Siberia

Harang discontinuity,

South Pole station, 1977

Connection solar wind – magnetosphere – ionosphere currents

Magnetometers of Prognoz-7, 8 and Interball satellites display the flapping movements of magnetopause in sequence with geomagnetic disturbances

Flapping motions of magnetosphere and vortexes formation

Flapping movements might stimulate the substorm mesoscale processes

UV Aurora as observed by Polar satellite at July 15, 2000

auroral oval as predicted

by GI , Alaska

X-ray imaging of particle precipitation

  • Global scale auroras are known to be similar, but how about mesoscales (L=100-1000 km)?

  • ASC images: evolution of individual auroral structures can also have interhemispheric similarities.

  • The real conjugate point of a station can move hundreds (tens) of km in longitude (latitude) during one hour.

  • Reference: Sato et al., GRL 2005

Example: Interhemispheric relationships in meso-scale auroras

Geophysical network on Yamal peninsula at 1972-1991.

Since 1972 there are analog recordings 20 mm/hour

Since 1985 first digital magnetometers were installed onDixon,

Bely Isl., Sabetta,

Cape Kamenny, Salekhard,

Analog data in WDC, digital data in Internet

Public Outreach and Education Program in Seykha School: Polar Geomagnetic Disturbances as Indicator of Space Weather (will plan to use THEMIS data )

Seykha School, Yamal peninsula, Siberia, Russia

geomagnetic latitude 65,0 degree

Thank you all colleagues that I have a chance to meet you !Sincerely , Alexander Zaitsev

My personal wish a great success to THEMIS project under leadership of Dr.V.Angelopulos !

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