Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements

Details Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements

Dec 2008

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufmsm53a1671s&link_type=abstract

American Geophysical Union, Fall Meeting 2008, abstract #SM53A-1671

Physics

6929 Ionospheric Physics (1240, 2400), 6939 Magnetospheric Physics (2700), 7811 Discontinuities (2109), 7836 Mhd Waves And Instabilities (2149, 2752, 6050), 7954 Magnetic Storms (2788)

Scientific paper

Statistical analysis of the main impulse (MI) amplitude of geomagnetic sudden commencements (SCs) observed from the dip equator to middle latitude has been made using the long-term geomagnetic field data obtained from the Yap (geomagnetic latitude, 0.38 degree), Gaum (5.22 degree), Okinawa (16.54 degree), Kakioka (27.18 degree), Memanbetsu (35.16 degree), and St. Paratunka (45.58 degree) stations. The magnetic local time (MLT) dependence of SC amplitude in the middle latitude showed the DP2-type magnetic field variations with its strong dawn-dusk asymmetry produced by ionospheric Hall currents which are driven by the dawn-to-dusk electric field accompanying a pair of field-aligned currents (FACs). The difference between the minimum and maximum values tends to become larger with increasing of magnetic latitude. In the low latitude, the maximum of the SC amplitude appears around noon (11:30, MLT), which means that the DL part of SC produced by the Chapman-Ferraro currents can be dominant in this region. However, the DP part of SC contaminated 5 percent of the DL one even in the low-latitude (16.54 degree). On the other hand, at the dip equator of the daytime sector between 8:00 and 16:00 (MLT), the equatorial enhancement of SC amplitude clearly appeared with its maximum amplitude of 3.24 (normalized SYM-H value) around 11:00 (MLT). Another interesting point is that the SC amplitude in the nighttime sector was enhanced at all the stations again, and its peak value increases with increasing of magnetic latitude. The nighttime enhancement is caused by the magnetic effects produced by the FACs associated with the MI phase of SC.

Affiliated with

Also associated with

No associations

Rating

Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic Latitude and Local Time Dependence of the Amplitude of Geomagnetic Sudden Commencements will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1099716