In recent lidar runs we’ve seen an increase in the return photon counts from the metal layers in the atmosphere. This could be due to a number of factors but the most likely reason is geomagnetic storms. When solar winds are sustained at high speeds directed opposite to Earths magnetic field, the solar winds can transfer energy in Earths magnetosphere, causing a geomagnetic storm. Geomagnetic storms can cause changes to many things, such as radiation belts, the ionosphere, and most importantly (for us) magnetic currents. When these geomagnetic storms occur we tend to see an increase in the metal layer photon counts in our systems. These periods are especially important for us to gather data because the data is higher quality and allows for new research opportunities. The metal layer photon return can increase by 2-3x during geomagnetic storms (depending on the lidar system).

A side effect of the high speed solar wind streams that cause geomagnetic storms is an intensification of the Auroral lights. With an increase in high energy particles from the sun comes an increase in the ionospheric interactions that cause the Aurora Australis. As such, we’ve gotten some great pictures of the Aurora these past few runs.

Above: Arrival Heights Laboratory with the STAR (Na lidar system) beam visible in front of an Aurora Australis

Left: Aurora Australis over the wind energy farm
Right: Aurora Australis in the night sky with a bit of the Na beam visible in the top left