Usually, aurorae are created when the magnetic field of a Coronal Mass Ejection (CME) from the Sun interacts with the magnetic field of Earth, known as the magnetosphere (Akasofu, 1991). The magnetosphere acts like a protective shield against the solar wind and space weather.  The process begins with magnetic reconnection on the dayside of Earth, causing magnetic field lines to be dragged back into the magnetotail. Magnetic flux in the magnetotail increases and leads to magnetic reconnection on the night-side. This night-side reconnection accelerates particles in the plasma sheet away from the point of reconnection. When magnetic reconnection occurs at the ring current, field-aligned currents (FACs) are set up, driving particles spiraling down Earth's magnetic field lines, toward the north and sound magnetic poles, into the ionosphere.

As electrons travel toward the poles they interact with atomic and molecular oxygen and nitrogen in the ionosphere. These interactions excite the atoms and molecules, which then release photons. This is the visible aurora.

CMEs are blobs of plasma. Plasma is often called the fourth state of matter and is basically super-heated, ionized gas (electrons and positive ions). One characteristic of plasma is that it can have a magnetic field. When the magnetic field of a CME interacts with the magnetosphere there are disturbances to the magnetic field of Earth. These disturbances are called geomagnetic storms. Waves are created in the magnetic field of Earth during geomagnetic storms (Cornilleau-Wehrlin, 2005).

My question is this: Can magnetic waves in the auroral region, created during geomagnetic storms, transform into sound waves?

1Sources:

Akasofu, S.-I. “Auroral Phenomena.” In: Meng, C.-I., M.J. Rycroft, and L.A. Frank (editors). Auroral Physics. Cambridge Univ. Press, 1991

Cornilleau-Wehrlin, N. “Magnetosphere of Earth: Waves.” Encyclopedia of Astronomy & Astrophysics [online], Nature Publishing Group, 2001/IoP Publishing, 2005

Next: Can we hear the aurorae?

How are aurorae created?
Can we hear the aurorae?
Wave transformation on the Sun
What is ß?
How can a magnetic wave transform into an acoustic wave?
Does ß=1 anywhere in Earth’s atmosphere?
Continuing research
Bibliography