First ice station: ready, set, go! A mass of red-clothed people flooded the ice and was ready to start their measurements – before a polar bear was spotted sitting on the same floe a couple hundred meters from the ship and sniffing around. Everyone was called back inside and we decided on a stricter polar bear protection mode, with additional people watching the bear at all times. A first test to our nerves. But all went well, we were able to successfully conduct our measurements on the ice: snow and ice properties in the footprint of the radiometers standing on the upper deck of the ship. And on the second day of the ice station, the polar bear had taken off, and the ice work could continue with slightly less jittery nerves.
When the excitement doesn’t come from the outside, you have to generate it yourself: on the last ice station day, we accidentally dropped a phone in one of our ice holes (its drilling can be seen in the picture above). The ice was already drilled down to the sea water, so the phone could have simply taken a 4000 m dive, but it got stuck on the icy walls of the hole, and fortunately the crew provided us with long gripping tongs and we could recover the phone. And we’re proud to announce that the phone is still working!
At the ice edge, we met Tara Polar Station, a drifting station for the polar regions, which is starting its first test drift through the Arctic sea ice now. It cannot break ice, so it waited for us at the ice edge, where it was anchored to Polarstern for a short meeting of the captains and so that the Taranauts (as we call them) could come over to Polarstern and get a break from the swaying and wobbling of the Tara Station which is a lot stronger than Polarstern’s roll and pitch. Later, they just followed in our ice-free path for one and a half days until they were far enough from the ice edge that they can drift through the ice for some time. Yesterday we said goodbye to Tara Polar Station and hope they have a good time drifting on!
Aaaand we’re off to another round: VAMPIRE-2 has started last week on board of the research vessel Polarstern as part of the CONTRASTS campaign. We boarded the ship in Tromsø where our amazing support team (Johanna, Nils, Pavel, and Mario) had already installed and calibrated most of the instruments on the deck of Polarstern the previous days. We set off towards the north and also installed the radiation sensors on a mast at the bow of the ship which now have to be cleaned regularly wearing a life vest and a harness. With all devices up and standing, we finally reached the ice edge yesterday morning and could start measuring sea ice emissivity on top of the ongoing atmospheric measurements. More importantly, we now take every opportunity to go outside and watch the sea ice, its always fluctuating shapes and colors as we pass through it. Stay tuned to hear of our first ice station coming soon!
After Polar 5 arrived yesterday, it was time to familiarize ourselves with the instruments and perform calibrations for the radar, the radiometer, and the spectrometers. We are ready for our first research flight tomorrow. Let’s go!
Time to celebrate! We received the great news that the CRC/TRR “Arctic Amplification(AC)³” will be funded by DFG for another 4 years (2024-2027). We are looking forward to continuing to do fascinating research in the high north!
Find below some press releases where you can read more about that:
As we reported earlier in this blog, we participated in the airborne field campaign HALO-(AC)³ In March and April 2022. The goal of the campaign was to improve the understanding of the airmasses transformation when transported into or out of the Arctic. Two types of airmass transports were of particular interest: First, moist and warm air intrusions that transport high amounts of heat and moisture from the mid-latitudes into the Arctic. Second, marine cold air outbreaks that lead to the formation of cloud streets and convective cells when cold and dry air from the central Arctic is transported southwards over the relatively warm North Atlantic. In our study, we analyse the weather (and sea ice) conditions during the HALO-(AC)³ campaign.
Map of the study area of the HALO-(AC)³ campaign including the flight tracks of the research aircraft HALO, Polar 5 (P5) and Polar 6 (P6). The study area has been separated into three subregions.
We separated the campaign into a warm and a cold period with the help of northwards humidity transport (IVT) and the so-called cold air outbreak index (MCAO index). The cold air outbreak indicates the strength of the temperature difference between the surface and the lower atmosphere. High differences suggest cold air outbreak conditions with strong interactions between the cold ocean and the atmosphere. The warm period was dominated by northward winds and warm air intrusions while the cold period featured several cold air outbreaks.
(a) Northward water vapour transport (IVTnorth) and (b) marine cold air outbreak (MCAO) index for the campaign duration in 2022 (black line). Grey shading indicates the climatology over the years 1979-2022. The red box shows the warm period, while the blue box illustrates the cold period.
During an extremely strong warm air intrusion, record breaking near-surface temperatures occurred in the central Arctic compared to the March 1979-2022 climatology. Also at Ny-Ålesund, the weather station recorded the highest near-surface temperatures for March since the beginning of the measurements in 1975. This warm air intrusion was detected as so-called Atmospheric River, a thin but long band of extremely strong moisture transport. Over the sea ice northwest of Svalbard, record breaking rainfall rates occurred.
Average 2 m temperature in March 2022 north of 80°N (red line). Thin black lines show the temperature for each year between 1979 and 2022 and the thick black line illustrates the average over those years.
At the beginning of the cold period, a strong cold air outbreak led to an extremely dry atmosphere over Ny-Ålesund with integrated water vapour content of just 1.1 kg m-2 (24 March 2022). Less than 3 % of all radiosondes launched since 1993 recorded drier conditions.
Humidity measurements from radiosondes (weather balloons) launched at Ny-Ålesund (Svalbard) during HALO-(AC)³. The colours indicate the specific humidity (fraction of water vapour mass to total air mass) while the black line shows the total humidity content of the troposphere (lowest layer of the atmosphere).
During the cold period, we also observed the Arctic version of a hurricane, a Polar Low. Polar Lows are characterised by convective (cumulus) clouds, relatively strong winds (at least gale force) and precipitation, while extending only over a few 100 kilometers. They also have a relatively cloud free centre like the eye of a hurricane. We analysed the environmental conditions for the formation of the Polar Low.
Photo taken from the research aircraft HALO during the flight to observe the Polar Low.
Luckily, the weather conditions were quite favourable to achieve the goals of the campaign because we could capture both types of airmass exchange between mid-latitudes and the Arctic. The publication has been submitted to the European Geosciences Union journal Atmospheric Chemistry and Physics.
The Transregional Collaborative Research Centre TR 172 (AC)³ and the University of Helsinki organized a joint winter school on Arctic amplification at the Hyytiälä Forestry Field Station in Finland. The field station is located about 200 km north of Helsinki in a boreal forest. This remote place served as the perfect place to learn about state-of-the-art observations of the atmosphere and biosphere.
Our daily program consisted of lectures in the morning by scientists from Europe and the U.S. and a combination of group work and field excursions in the afternoon. The lectures covered all research topics of (AC)³: surface energy budget over sea ice and open ocean, cloud microphysics, aerosols, ocean and atmosphere remote sensing, climate feedback mechanisms, Arctic water cycle, atmospheric rivers, and polar-midlatitude linkages. A highlight was an excursion to the meteorological towers that observe for example the formation of new aerosol particles and the deposition of CO₂ by the forest (see photos below).
Group photo in front of the old dining hall. (Photo: Christa Genz)94 GHz cloud radar (left) and microwave radiometer (right) observing clouds, precipitation, and thermodynamic profiles above the boreal forest. (Photo: Christa Genz)The 127 m high tower SMEAR II.A sonic anemometer above the canopy.
This week Mario and myself traveled to Ny-Ålesund, Svalbard, to exchange our cloud radar MiRAC-A with the cloud radar JOYRAD94. Since MiRAC-A is needed for campaign preparations, it has to travel back to Germany. Swapping the instruments on the roof of the atmospheric observatory of AWIPEV (https://www.awipev.eu/) went very smoothly.
Crane operation to lift the cloud radar JOYRAD94 on top of the AWIPEV atmospheric observatory
Thanks also to the AWIPEV and Kingsbay support! What a wonderful place to do measurements!
In December, Kerstin was interviewed by a journalist in the local newspaper “Kölnische Rundschau”. The article (in German) about climate change in the Arctic and about our measurement activities in the Arctic, in particular at AWIPEV (Ny-Ålesund, Svalbard), was published on Dec 27, 2022.
What is it about?
The article highlights the importance of long-term data and data analysis for climate studies. It is always great to have the chance to communicate our science to the broader public! And of course it is a challenge as well…
When the COVID-19 pandemic started, scientist around the world migrated quickly to online meeting and zoom conferences. However, if there is something that we all can conclude after this experience, it is the fact that nothing can replace the experience of face-to-face meetings. Not only because of the interactions between the colleagues and scientific discussions that take places everywhere, but also the experience to visit different places, cities, and cultures. Next, you can read the experience of Kerstin Ebell, member of AWARES:
In August, Susanne, Rosa and me went to the American Meteorological Society (AMS) Collective Madison Meeting at Madison, Wisconsin. The conference collection was about cloud physics, polar meteorology and oceanography, atmospheric radiation and satellite applications. After 2 years, this was my first international travel, and I was very excited to go. It was really great to meet international colleagues again and see old and new faces!
We had very good discussions during and around the conference and could enjoy the city of Madison (with an impressive water ski show!) and the hospitality of our American colleagues. My non-conference highlight was the corncob that we had for dinner at a friends place. So delicious! Sometimes the simplest things are the best things in life…
Left: Sunset at the Memorial Union Terrace at Madison. Right: Kerstin Ebell’s poster.
