Snow White and the 7 flights

Today we took off for the 7th and last time with Polar 5. With a newly mixed crew, all PhDs were able to fly again, one of them even made her debut as PI. Mika actively supported her and helped, for example, to write the flight log.
As a PI, of course, you also have other tasks. The day before, the flight route has to be planned and a flight plan has to be written and sent out. During the flight, you have to keep an eye on the flight altitude and the times when the planned points are reached. You also communicate with the pilots from time to time and make sure that all measurements are started and finished at the right time. But of course, everyone thinks along and knows what to do with their instruments, so they make it easier for you to complete the PI tasks.
The view during the flight was great again – we flew over Porsangerfjord on the north coast of Norway, where we could observe the cloud cover thickening towards the north. On the satellite track we launched 5 dropsondes this time and the satellite flew over us in such a way that Polar 5 can be seen again as a signal in the EarthCARE radar data!
Everyone was very happy with this last flight. But Mika was also a little sad because it was the last flight for COMPEX-EC and he had enjoyed flying so much. But the next campaign is sure to come and you can also look forward to a final blog entry in which we look back on the campaign and say goodbye to you!

From watching clouds to eating chocolate cake

Yesterday’s flight took us out over the open sea, where we expected to see some beautiful convective clouds towering up to 4 km. That meant we had to climb higher again — this time to about 4.5 km. Just before takeoff, we checked the latest satellite images and saw that we’d be flying right into a cold air outbreak (CAO) combined with a small low-pressure system moving eastward towards the Barents Sea. Such weather conditions are always fascinating to fly in, as you can expect an interesting mix of clouds and clear sky. In a CAO, cold air is advected over the relatively warm ocean, leading to a strong temperature difference between the sea surface and the higher layers of the troposphere. This causes the atmosphere near the ground to become unstable – the air can rise, cool down – and condensation occurs: clouds form that can tower up impressively. These promising prospects were, of course, particularly exciting for Mika. During the flight, he carefully monitored the dropsondes – and even threw one or two of them out of the plane himself (but only once they were ready for measurement, of course!). And when there was nothing to do, he was busy taking photos of the beautiful clouds that we were able to admire during our flight. Thanks to Mika, we were able to drop a total of 9 dropsondes, the highest number ever during our campaign! This flight was truly special, as our PI of this flight, Marcus, had his 40th birthday! After landing back in Kiruna, our ground team surprised him with a chocolate birthday cake. Naturally, we gathered the whole crew for a birthday photo. Not only did we have a successful flight with lots of stunning clouds along our track, but we also had a special birthday celebration for our PI. Happy 40th birthday, Marcus!

From runway to bowling lane

After two days without a flight, today we could finally take off again. The conditions could have been a little better, but that didn’t stop us from flying to continue our research. The forecast was clear – higher clouds than on the first flights, which is why we needed to go up to over 5 km. But before we got on the plane, the group photo of the entire COMPEX-EC crew was on the agenda. A perfect photo on the first try, and we were ready to board the plane.
The EarthCARE track north of Kiruna over the Norwegian Sea was well suited for the day and the planning focused on flying on the track against and with the satellite flight direction. In addition, dropsondes on a regular grid were launched to provide more precise vertical profiles on the way there and back.
Said, done!
The flight went very well with 6 dropsondes and the EarthCARE underflight. We were also able to observe interesting clouds again, including the typical cellular convection pattern of a cold-air outbreak and some showers. As Polar 5 had to stand outside during the nights, frozen water persisted on the windows, but did not stop us from taking pictures of the cloud formations.
After the successful completion of also this research flight, the fifth successful one by the way, the team enjoyed an evening together in the bowling center. The pins were hit just as well as we matched EarthCARE satellite with our flights – Doublestrike! Mika also took part, but clearly had a hard time with the big bowling balls.
Stay tuned, because the campaign is not over yet!

From Polar Lights to Polar Flights – COMPEX-EC Takes Off!

After we arrived in Kiruna yesterday and were greeted with polar lights, today our research aircraft Polar 5 has landed – ready to begin the COMPEX-EC campaign! Over the next two weeks, we will conduct research flights, focusing on cloud analysis in connection with the recently launched EarthCARE satellite.
With all participants and equipment in place, flight planning is already in full swing. Using the mission support system (MSS), we are mapping out possible flight paths on a large screen. One of our key challenges? Aligning our flight tracks with the EarthCARE satellite’s orbit to ensure at least 30 minutes of overlapping observations. This requires precise coordination — timing is everything.
Another critical factor is the weather. We are analyzing weather maps to identify optimal conditions for our flights. Especially cloud coverage and wind play a role in deciding when and where we can fly. Together with Jonas from ESA, we have already had an extensive weather briefing, and the forecasts look promising for our first flight, expected to take place this Friday.
Our (AC)³ mascot, Arctic fox Mika, could also hardly wait to see Polar 5 land here. With big eyes, he watched with us as the research aircraft was maneuvered into the hangar and, of course, made sure that everything went smoothly when the luggage was removed.
Of course, we also took a look inside the cockpit with him.
He is really looking forward to this time and hopes to discover and experience a lot more.
Exciting days lie ahead— stay tuned as we share our experiences, flight updates, and first results right here on the blog!

Ready…Set…Go!

Over the last two weeks, instruments were installed, cables laid, and the seats tightened into the aircraft to prepare for the COMPEX-EC (Clouds over cOMPlEX environment – EarthCARE) campaign in Kiruna. During the first half of April (2.-16.4.2025), scientists from the Universities of Cologne and Leipzig will conduct an EarthCARE validation campaign with the Polar 5 research aircraft from the Alfred Wegener Institute. Equipped with a suite of cloud remote sensing instruments, we will make research flights along the track of the overpassing EarthCARE satellite to validate its performance. Stay tuned for some impressions and regular updates from Kiruna.