Effect of magnetospheric history to magnetopause energy transfer
(Minna Palmroth)

Objective

Recently, there has been indications that the magnetopause energy transfer depends on the past history of the energy transfer, such that prior large energy input tends to increase the instantaneous energy transfer. In particular, a recent study suggests that in IMF rotations, the energy input at a certain clock angle (theta) is larger, if the IMF rotated there past the maximum energy input angle (theta = 180). Here the objective is to test the scenario by statistical means.

Exercise outline

Given a large solar wind data base of hourly averages, find cases where the clock angle is about 230 degrees. Divide the data set in two groups: one in which the clock angle rotated to the 230 degrees through theta = 180 (clockwise), and one in which the IMF rotated to the 230 degrees counterclockwise. For each case, find from another data set a Polar Cap Index (PCI), and plot the PCI values for the two groups. Is there a magnitude difference? If yes, can it be an indication that the energy input was larger for the other group, even though the IMF clock angle for the two groups was similar - only the rotation direction was different?

Data


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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 469home page