IOP4 is now over after fog came rolling in and caused heavy icing on the SUMO at around 3:30 local time last night. Before that, we measured several cold pool events with up to 4°C difference over a vertical distance of 5 meters. The first pronounced cold pool event started at 14 UTC and ended around 16 UTC (18 local time, around sunset) when winds were picking up a bit. We did several profiles with our drones during this event and look forward to look more closely at the data from the different instruments. The second cold pool event started around 20 UTC and was flavoured with beautiful northern lights. As the weather conditions are still good, we aim for a short IOP this evening. But first some rest…
Evolution of temperature at around 1 m (pink), 2 m (light green) and 7 m (dark green) from our weather mast at 18 February from about 8 to 0 UTC. IOP4 started at 14 UTC.
Launching the SUMO at sunset during the first cold pool event of IOP4.
SUMO flight and northern lights during the second cold pool event. The bright arc on the left of the picture is the track of our SUMO.