2020, Lampert, Astrid, Altstädter, Barbara, Bärfuss, Konrad, Bretschneider, Lutz, Sandgaard, Jesper, Michaelis, Janosch, Lobitz, Lennart, Asmussen, Magnus, Damm, Ellen, Käthner, Ralf, Krüger, Thomas, Lüpkes, Christof, Nowak, Stefan, Peuker, Alexander, Rausch, Thomas, Reiser, Fabian, Scholtz, Andreas, Zakharov, Denis Sotomayor, Gaus, Dominik, Bansmer, Stephan, Wehner, Birgit, Pätzold, Falk

Unmanned aerial systems (UAS) fill a gap in high-resolution observations of meteorological parameters on small scales in the atmospheric boundary layer (ABL). Especially in the remote polar areas, there is a strong need for such detailed observations with different research foci. In this study, three systems are presented which have been adapted to the particular needs for operating in harsh polar environments: The fixed-wing aircraft M2AV with a mass of 6 kg, the quadrocopter ALICE with a mass of 19 kg, and the fixed-wing aircraft ALADINA with a mass of almost 25 kg. For all three systems, their particular modifications for polar operations are documented, in particular the insulation and heating requirements for low temperatures. Each system has completed meteorological observations under challenging conditions, including take-offand landing on the ice surface, low temperatures (down to-28 °C), icing, and, for the quadrocopter, under the impact of the rotor downwash. The influence on the measured parameters is addressed here in the form of numerical simulations and spectral data analysis. Furthermore, results from several case studies are discussed: With the M2AV, low-level flights above leads in Antarctic sea ice were performed to study the impact of areas of open water within ice surfaces on the ABL, and a comparison with simulations was performed. ALICE was used to study the small-scale structure and short-term variability of the ABL during a cruise of RV Polarstern to the 79° N glacier in Greenland. With ALADINA, aerosol measurements of different size classes were performed in Ny-Alesund, Svalbard, in highly complex terrain. In particular, very small, freshly formed particles are difficult to monitor and require the active control of temperature inside the instruments. The main aim of the article is to demonstrate the potential of UAS for ABL studies in polar environments, and to provide practical advice for future research activities with similar systems. © 2020 by the authors.

2022, Schön, Martin, Suomi, Irene, Altstädter, Barbara, van Kesteren, Bram, zum Berge, Kjell, Platis, Andreas, Wehner, Birgit, Lampert, Astrid, Bange, Jens

The wind field in Arctic fjords is strongly influenced by glaciers, local orography and the interaction between sea and land. Ny-Ålesund, an important location for atmospheric research in the Arctic, is located in Kongsfjorden, a fjord with a complex local wind field that influences measurements in Ny-Ålesund. Using wind measurements from UAS (unmanned aircraft systems), ground measurements, radiosonde and reanalysis data, characteristic processes that determine the wind field around Ny-Ålesund are identified and analysed. UAS measurements and ground measurements show, as did previous studies, a south-east flow along Kongsfjorden, dominating the wind conditions in Ny-Ålesund. The wind measured by the UAS in a valley 1 km west of Ny-Ålesund differs from the wind measured at the ground in Ny-Ålesund. In this valley, we identify a small-scale catabatic flow from the south to south-west as the cause for this difference. Case studies show a backing (counterclockwise rotation with increasing altitude) of the wind direction close to the ground. A katabatic flow is measured near the ground, with a horizontal wind speed up to 5 m s-1. Both the larger-scale south-east flow along the fjord and the local katabatic flows lead to a highly variable wind field, so ground measurements and weather models alone give an incomplete picture. The comparison of UAS measurements, ground measurements and weather conditions analysis using a synoptic model is used to show that the effects measured in the case studies play a role in the Ny-Ålesund wind field in spring.

2020, Petäjä, Tuukka, Duplissy, Ella-Maria, Tabakova, Ksenia, Schmale, Julia, Altstädter, Barbara, Ancellet, Gerard, Arshinov, Mikhail, Balin, Yurii, Baltensperger, Urs, Bange, Jens, Beamish, Alison, Belan, Boris, Berchet, Antoine, Bossi, Rossana, Cairns, Warren R.L., Ebinghaus, Ralf, El Haddad, Imad, Ferreira-Araujo, Beatriz, Franck, Anna, Huang, Lin, Hyvärinen, Antti, Humbert, Angelika, Kalogridis, Athina-Cerise, Konstantinov, Pavel, Lampert, Astrid, MacLeod, Matthew, Magand, Olivier, Mahura, Alexander, Marelle, Louis, Masloboev, Vladimir, Moisseev, Dmitri, Moschos, Vaios, Neckel, Niklas, Onishi, Tatsuo, Osterwalder, Stefan, Ovaska, Aino, Paasonen, Pauli, Panchenko, Mikhail, Pankratov, Fidel, Pernov, Jakob B., Platis, Andreas, Popovicheva, Olga, Raut, Jean-Christophe, Riandet, Aurélie, Sachs, Torsten, Salvatori, Rosamaria, Salzano, Roberto, Schröder, Ludwig, Schön, Martin, Shevchenko, Vladimir, Skov, Henrik, Sonke, Jeroen E., Spolaor, Andrea, Stathopoulos, Vasileios K., Strahlendorff, Mikko, Thomas, Jennie L., Vitale, Vito, Vratolis, Sterios, Barbante, Carlo, Chabrillat, Sabine, Dommergue, Aurélien, Eleftheriadis, Konstantinos, Heilimo, Jyri, Law, Kathy S., Massling, Andreas, Noe, Steffen M., Paris, Jean-Daniel, Prévôt, André S.H., Riipinen, Ilona, Wehner, Birgit, Xie, Zhiyong, Lappalainen, Hanna K.

The role of polar regions is increasing in terms of megatrends such as globalization, new transport routes, demography, and the use of natural resources with consequent effects on regional and transported pollutant concentrations. We set up the ERA-PLANET Strand 4 project “iCUPE – integrative and Comprehensive Understanding on Polar Environments” to provide novel insights and observational data on global grand challenges with an Arctic focus. We utilize an integrated approach combining in situ observations, satellite remote sensing Earth observations (EOs), and multi-scale modeling to synthesize data from comprehensive long-term measurements, intensive campaigns, and satellites to deliver data products, metrics, and indicators to stakeholders concerning the environmental status, availability, and extraction of natural resources in the polar areas. The iCUPE work consists of thematic state-of-the-art research and the provision of novel data in atmospheric pollution, local sources and transboundary transport, the characterization of arctic surfaces and their changes, an assessment of the concentrations and impacts of heavy metals and persistent organic pollutants and their cycling, the quantification of emissions from natural resource extraction, and the validation and optimization of satellite Earth observation (EO) data streams. In this paper we introduce the iCUPE project and summarize initial results arising out of the integration of comprehensive in situ observations, satellite remote sensing, and multi-scale modeling in the Arctic context.