skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: High-latitude dayside electric fields and currents during strong northward interplanetary magnetic field: Observations and model simulation

Journal Article · · J. Geophys. Res.; (United States)

On July 23, 1983, the Interplanetary Magnetic Field turned strongly northward, becoming about 22 nT for several hours. Using a combined data set of ionospheric convection measurements made by the Sondre Stromfjord incoherent scatter radar and convection inferred from Greenland magnetometer measurements, we observe the onset of the reconfiguration of the high-latitude ionospheric currents to occur about 3 min following the northward IMF encountering the magnetopause. The large-scale reconfiguration of currents, however, appears to evolve over a period of about 22 min. Using a computer model in which the distribution of field-aligned current in the polar cleft is directly determined by the strength and orientation of the interplanetary electric field, we are able to simulate the time-varying pattern of ionospheric convection, including the onset of high-latitude ''reversed convection'' cells observed to form during the interval of strong northward IMF. These observations and the simulation results indicate that the dayside polar cap electric field observed during strong northward IMF is produced by a direct electrical current coupling with the solar wind. copyright American Geophysical Union 1988

Research Organization:
Space, Telecommunications and Radioscience Laboratory, Stanford Electronics Laboratories, Stanford University, Stanford, California
OSTI ID:
5190170
Journal Information:
J. Geophys. Res.; (United States), Vol. 93:A4
Country of Publication:
United States
Language:
English