Details

Autor(en) / Beteiligte

• Nishitani, Nozomu
• Ogawa, Tadahiko
• Pinnock, Mike
• Freeman, Mervyn P.
• Dudeney, John R.
• Villain, Jean‐Paul
• Baker, Kile B.
• Sato, Natsuo
• Yamagishi, Hisao
• Matsumoto, Haruhisa

Titel

A very large scale flow burst observed by the SuperDARN radars

Ist Teil von

• Journal of Geophysical Research, Washington, DC, 1999-10, Vol.104 (A10), p.22469-22486

Ort / Verlag

Washington, DC: Blackwell Publishing Ltd

Erscheinungsjahr

1999

Quelle

Access via Wiley Online Library

Beschreibungen/Notizen

• We examined the dynamics of the ionospheric plasma in the dayside sector by using the HF radar data at Iceland West and at Finland from 1100 to 1230 UT on September 5, 1995. During that period, the solar wind density was high and the IMF was strongly southward. The dayside magnetopause was highly compressed nearly to the geosynchronous orbit. The two radars simultaneously detected a poleward flow burst in the noon sector which, assuming uniformity of flow in the region of the data gap (1.5 MLT) between the two radars, showed a magnetic local time extent of 5 hours. This local time extent is 2 to 3 hours wider than previous results. The maximum poleward plasma velocity of the flow burst is ∼750 m/s, and the latitudinal size of the flow burst region is ∼100 to 200 km. This flow burst region initially expanded in longitude up to 5 hours, and then shifted poleward with a phase speed of 400 to 670 m/s. The flow burst has a duration of ∼20 min. This large‐scale poleward flow burst is likely to be due to large‐scale reconnection occurring at the dayside magnetopause and subsequent convection as the magnetic field lines are transported across the polar cap.