Large Amplitude Alfven Waves and "Spikey" Electric and Magnetic Fields observed within the High Latitude Ionosphere with the Dynamics Explorer-2 Satellite

The high time resolution (16 s/sec) vector electric field and magnetic field measurements gathered on NASA's Dynamics Explorer-2 satellite reveal numerous examples of large amplitude Alfven waves in the high latitude ionosphere, with amplitudes that are often 100's of mV/m and 100's of nT. The waves appear in packets that typically extend for 10-60 seconds along the satellite track (100-500 km horizontal distance), with characteristic wave periods on the order of a second or less. In some cases, the wave amplitudes include well defined, periodic "spikes" separated by 10-20 seconds. We present a new analysis of the vector electric field and magnetic field data on DE-2 to reveal Poynting Flux energy flux associated with the Alfven wave and structured fields.

The data are analyzed in conjunction with energetic particle observations as well as magnetic activity. The new, detailed findings present a new perspective on magnetosphere-ionosphere coupling at high latitudes, including energy deposition and momentum exchange at different spatial and temporal scales during disturbed conditions.