Objective
To understand the differences in auroral electrojet activity between the
Northern and Southern Hemispheres.
Exercise outline
The student will get a data base of northern and southern hemispheric
observations of the auroral electrojet currents as deduced from the
magnetic field data of the CHAMP satellite with the method of Juusola
et al. 2006. The data set will include the time and location information
of the satellite overpasses and current intensities. Also the solar
wind data from the ACE-satellite will be given (month files).
Steps of work:
- Conversion of the CHAMP location information and current vectors to
the magnetic dipole coordinate system (conversion routine will be available).
- Search those orbits (called Half Orbits of Constant MLT, HOCM) where the
satellite has crossed the northern and southern electrojets roughly along
the same MLT longitude (within 1 hour accuracy) and within UT-time period
of 60 minutes.
- Determining from the ACE data set the corresponding solar wind
conditions for the HOCM events, and selection for further analysis only
those HOCM with constant enough solar wind conditions (appropriate
thresholds to be defined during the work).
- Determining the season, MLT, IMF Bx, By, and Bz distribution of the
selected HOCM events.
- Investigate how big differences there are in the intensity, location,
and structure (latitude variations) of the southern and northern
electrojets as functions of season, MLT, and IMF.
Back to exercises
Contact course assistant:
Minna Palmroth_at_fmi.fi (replace _at_ with @)
Finnish Meteorological Institute, Space Research
Erik Palmenin aukio 1, (Dynamicum)
Room 1D11a, 09-1929 4696
home page
|