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1. Atmospheric and Surface Processes, and Feedback Mechanisms Determining Arctic Amplification: A Review of First Results and Prospects of the (AC)3 Project

Author

Wendisch, M., Brückner, M., Crewell, Susanne, Ehrlich, A., Notholt, J., Lüpkes, C., Macke, A., Burrows, J. P., Rinke, A., Quaas, J., Maturilli, M., Schemann, V., Shupe, M. D., Akansu, E. F., Barrientos-Velasco, C., Bärfuss, K., Blechschmidt, A.-M., Block, K., Bougoudis, I., Bozem, H., Böckmann, C., Bracher, A., Bresson, H., Bretschneider, L., Buschmann, M., Chechin, D. G., Chylik, J., Dahlke, S., Deneke, H., Dethloff, K., Donth, T., Dorn, W., Dupuy, R., Ebell, K., Egerer, U., Engelmann, R., Eppers, O., Gerdes, R., Gierens, R., Gorodetskaya, I. V., Gottschalk, M., Griesche, H., Gryanik, V. M., Handorf, D., Harm-Altstädter, B., Hartmann, J., Hartmann, M., Heinold, B., Herber, A., Herrmann, H., Heygster, G., Höschel, I., Hofmann, Z., Hölemann, J., Hünerbein, A., Jafariserajehlou, S., Jäkel, E., Jacobi, C., Janout, M., Jansen, F., Jourdan, O., Jurányi, Z., Kalesse-Los, H., Kanzow, T., Käthner, R., Kliesch, L. L., Klingebiel, M., Knudsen, E. M., Kovács, T., Körtke, W., Krampe, D., Kretzschmar, J., Kreyling, D., Kulla, B., Kunkel, D., Lampert, A., Lauer, M., Lelli, L., von Lerber, A., Linke, O., Löhnert, U., Lonardi, M., Losa, S. N., Losch, M., Maahn, M., Mech, M., Mei, L., Mertes, S., Metzner, E., Mewes, D., Michaelis, J., Mioche, G., Moser, Manuel, Nakoudi, K., Neggers, R., Neuber, R., Nomokonova, T., Oelker, J., Papakonstantinou-Presvelou, I., Pätzold, F., Pefanis, V., Pohl, C., van Pinxteren, M., Radovan, A., Rhein, M., Rex, Markus, Richter, A., Risse, N., Ritter, C., Rostosky, P., Rozanov, V. V., Ruiz Donoso, E., Saavedra-Garfias, P., Salzmann, M., Schacht, J., Schäfer, M., Schneider, J., Schnierstein, N., Seifert, P., Seo, S., Siebert, H., Soppa, M. A., Spreen, G., Stachlewska, I. S., Stapf, J., Stratmann, F., Tegen, I., Viceto, C., Voigt, Christiane, Vountas, M., Walbröl, A., Walter, M., Wehner, B., Wex, H., Willmes, S., Zanatta, M., Zeppenfeld, S., Laboratoire de Météorologie Physique (LaMP), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, [SDU]Sciences of the Universe [physics], clouds, Arctic amplification
Abstract

Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC)3 project was established in 2016 (www.ac3-tr.de/). It comprises modeling and data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, shipborne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data. For example, a distinct atmospheric moistening, an increase of regional storm activities, an amplified winter warming in the Svalbard and North Pole regions, and a decrease of sea ice thickness in the Fram Strait and of snow depth on sea ice have been identified. A positive trend of tropospheric bromine monoxide (BrO) column densities during polar spring was verified. Local marine/biogenic sources for cloud condensation nuclei and ice nucleating particles were found. Atmospheric–ocean and radiative transfer models were advanced by applying new parameterizations of surface albedo, cloud droplet activation, convective plumes and related processes over leads, and turbulent transfer coefficients for stable surface layers. Four modes of the surface radiative energy budget were explored and reproduced by simulations. To advance the future synthesis of the results, cross-cutting activities are being developed aiming to answer key questions in four focus areas: lapse rate feedback, surface processes, Arctic mixed-phase clouds, and airmass transport and transformation.

Published
2023
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2. Atmospheric and Surface Processes, and Feedback Mechanisms Determining Arctic Amplification: A Review of First Results and Prospects of the (AC)3 Project

Author

Wendisch, M, Brückner, M, Crewell, S, Ehrlich, A, Notholt, J, Lüpkes, C, Macke, A, Burrows, JP, Rinke, A, Quaas, J, Maturilli, M, Schemann, V, Shupe, MD, Akansu, EF, Barrientos-Velasco, C, Bärfuss, K, Blechschmidt, A-M, Block, K, Bougoudis, I, Bozem, H, Böckmann, C, Bracher, A, Bresson, H, Bretschneider, L, Buschmann, M, Chechin, DG, Chylik, J, Dahlke, S, Deneke, H, Dethloff, K, Donth, T, Dorn, W, Dupuy, R, Ebell, K, Egerer, U, Engelmann, R, Eppers, O, Gerdes, R, Gierens, R, Gorodetskaya, IV, Gottschalk, M, Griesche, H, Gryanik, VM, Handorf, D, Harm-Altstädter, B, Hartmann, J, Hartmann, M, Heinold, B, Herber, A, Herrmann, H, Heygster, G, Höschel, I, Hofmann, Z, Hölemann, J, Hünerbein, A, Jafariserajehlou, S, Jäkel, E, Jacobi, C, Janout, M, Jansen, F, Jourdan, O, Jurányi, Z, Kalesse-Los, H, Kanzow, T, Käthner, R, Kliesch, LL, Klingebiel, M, Knudsen, EM, Kovács, T, Körtke, W, Krampe, D, Kretzschmar, J, Kreyling, D, Kulla, B, Kunkel, D, Lampert, A, Lauer, M, Lelli, L, von Lerber, A, Linke, O, Löhnert, U, Lonardi, M, Losa, SN, Losch, M, Maahn, M, Mech, M, Mei, L, Mertes, S, Metzner, E, Mewes, D, Michaelis, J, Mioche, G, Moser, M, Nakoudi, K, Neggers, R, Neuber, R, Nomokonova, T, Oelker, J, Papakonstantinou-Presvelou, I, Pätzold, F, Pefanis, V, Pohl, C, van Pinxteren, M, Radovan, A, Rhein, M, Rex, M, Richter, A, Risse, N, Ritter, C, Rostosky, P, Rozanov, VV, Donoso, E Ruiz, Saavedra Garfias, P, Salzmann, M, Schacht, J, Schäfer, M, Schneider, J, Schnierstein, N, Seifert, P, Seo, S, Siebert, H, Soppa, MA, Spreen, G, Stachlewska, IS, Stapf, J, Stratmann, F, Tegen, I, Viceto, C, Voigt, C, Vountas, M, Walbröl, A, Walter, M, Wehner, B, Wex, H, Willmes, S, Zanatta, M, Zeppenfeld, S, Wendisch, M, Brückner, M, Crewell, S, Ehrlich, A, Notholt, J, Lüpkes, C, Macke, A, Burrows, JP, Rinke, A, Quaas, J, Maturilli, M, Schemann, V, Shupe, MD, Akansu, EF, Barrientos-Velasco, C, Bärfuss, K, Blechschmidt, A-M, Block, K, Bougoudis, I, Bozem, H, Böckmann, C, Bracher, A, Bresson, H, Bretschneider, L, Buschmann, M, Chechin, DG, Chylik, J, Dahlke, S, Deneke, H, Dethloff, K, Donth, T, Dorn, W, Dupuy, R, Ebell, K, Egerer, U, Engelmann, R, Eppers, O, Gerdes, R, Gierens, R, Gorodetskaya, IV, Gottschalk, M, Griesche, H, Gryanik, VM, Handorf, D, Harm-Altstädter, B, Hartmann, J, Hartmann, M, Heinold, B, Herber, A, Herrmann, H, Heygster, G, Höschel, I, Hofmann, Z, Hölemann, J, Hünerbein, A, Jafariserajehlou, S, Jäkel, E, Jacobi, C, Janout, M, Jansen, F, Jourdan, O, Jurányi, Z, Kalesse-Los, H, Kanzow, T, Käthner, R, Kliesch, LL, Klingebiel, M, Knudsen, EM, Kovács, T, Körtke, W, Krampe, D, Kretzschmar, J, Kreyling, D, Kulla, B, Kunkel, D, Lampert, A, Lauer, M, Lelli, L, von Lerber, A, Linke, O, Löhnert, U, Lonardi, M, Losa, SN, Losch, M, Maahn, M, Mech, M, Mei, L, Mertes, S, Metzner, E, Mewes, D, Michaelis, J, Mioche, G, Moser, M, Nakoudi, K, Neggers, R, Neuber, R, Nomokonova, T, Oelker, J, Papakonstantinou-Presvelou, I, Pätzold, F, Pefanis, V, Pohl, C, van Pinxteren, M, Radovan, A, Rhein, M, Rex, M, Richter, A, Risse, N, Ritter, C, Rostosky, P, Rozanov, VV, Donoso, E Ruiz, Saavedra Garfias, P, Salzmann, M, Schacht, J, Schäfer, M, Schneider, J, Schnierstein, N, Seifert, P, Seo, S, Siebert, H, Soppa, MA, Spreen, G, Stachlewska, IS, Stapf, J, Stratmann, F, Tegen, I, Viceto, C, Voigt, C, Vountas, M, Walbröl, A, Walter, M, Wehner, B, Wex, H, Willmes, S, Zanatta, M, and Zeppenfeld, S

Abstract

Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC)3 project was established in 2016 (www.ac3-tr.de/). It comprises modeling and data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, shipborne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data. For example, a distinct atmospheric moistening, an increase of regional storm activities, an amplified winter warming in the Svalbard and North Pole regions, and a decrease of sea ice thickness in the Fram Strait and of snow depth on sea ice have been identified. A positive trend of tropospheric bromine monoxide (BrO) column densities during polar spring was verified. Local marine/biogenic sources for cloud condensation nuclei and ice nucleating particles were found. Atmospheric–ocean and radiative transfer models were advanced by applying new parameterizations of surface albedo, cloud droplet activation, convective plumes and related processes over leads, and turbulent transfer coefficients for stable surface layers. Four modes of the surface radiative energy budget were explored and reproduced by simulations. To advance the future synthesis of the results, cross-cutting activities are being developed aiming to answer key questions in four focus areas: lapse rate feedback, surface processes, Arctic mixed-phase clouds, and airmass transport and transformation.

Published
2023

4. Investigating the potential to retrieve cloud droplet number concentration from ship-based measurements of spectral solar radiance during EUREC4A

Author

Ehrlich, A., Stapf, J., Emmanouilidis, A., Wolf, K., Schäfer, M., Kalesse-Los, H., Ehrlich, A., Stapf, J., Emmanouilidis, A., Wolf, K., Schäfer, M., and Kalesse-Los, H.

Abstract

Ship-based cloud remote sensing observations made onboard R/V Meteor during the ElUcidating the RolE of Cloud-Circulation Coupling in ClimAte, EUREC4A, campaign are presented and used to calculate cloud droplet number concentrations. The calculation is based on cloud liquid water path LWP and droplet effective radius reff retrieved from spectral measurements of transmitted solar radiance. It is shown that measurement uncertainties and retrieval assumptions impact the accuracy of the results. A case study indicates that the retrieval of LWP and reff is most affected by 3D-radiative effects in case of shallow cumulus and drizzle, which violates the adiabatic theory and plan-parallel geometry on which the radiative transfer simulations of the retrieval are based. Depending on the cloud thickness, the retrieval of reff might suffers from ambiguity. These retrieval uncertainties and their implications on the estimated cloud droplet number concentration are investigated by a sensitivity study. The analysis showed that most of the uncertainty is introduced by reff, whereas LWP contributes significantly to the uncertainty only for thin clouds. Therefore, it is concluded that only selected cloud cases, which do not violate the retrieval assumption, such as stratiform cloud layers, are suited to apply the retrieval approach in further studies., Fernerkundungsmessungen von Wolken auf dem Forschungsschiff R/V Meteor während der ElUcidating the RolE of Cloud-Circulation Coupling in ClimAte, EUREC4A, Kampagnewerden vorgestellt und zur Berechnung der Tröpfchenanzahlkonzentration verwendet. Die Berechnung basiert auf Messungen des Flüssigwasserpfads LWP und dem effektiven Tröpfchenradius reff, welche aus spektralen Messungen der transmittierten solaren Strahldichte abgeleitet wurden. Es wird gezeigt, dass Messunsicherheiten und Annahmen bei der Ableitung der Wolkeneigenschaften die Genauigkeit der Ergebnisse beeinflussen. Eine Fallstudie zeigt, dass die Ableitung von LWP und reff am stärksten durch 3-dimensionale Strahlungseffekte von flachen Cumuli und Nieselregen beeinflusst wird. Beides wiederspricht den Idealisierungen von adiabatischen Wolken und einer planparallelen Geometrie, auf denen die Strahlungstransfersimulationen des Verfahrens beruhen. Abhängig von der Wolkendicke kann die Ableitung von reff zusätzlich durch Mehrdeutigkeiten beeinflusst sein.

Published
2022

6. EUREC4A: Overview of LIM contributions

Author

Luebke, A. E., Röttenbacher, J., Ehrlich, A., Schäfer, M., Wolf, K., Kalesse-Los, H., Wendisch, M., Stapf, J., and Thoböll, J.

Subjects
Wind, Mesosphäre, Oszillation, ddc:551, wind, mesosphere, oscillation
Published
2021

9. MOSAiC-ACA and AFLUX - Arctic airborne campaigns characterizing the exit area of MOSAiC.

Author

Mech M, Ehrlich A, Herber A, Lüpkes C, Wendisch M, Becker S, Boose Y, Chechin D, Crewell S, Dupuy R, Gourbeyre C, Hartmann J, Jäkel E, Jourdan O, Kliesch LL, Klingebiel M, Kulla BS, Mioche G, Moser M, Risse N, Ruiz-Donoso E, Schäfer M, Stapf J, and Voigt C

Abstract

Two airborne field campaigns focusing on observations of Arctic mixed-phase clouds and boundary layer processes and their role with respect to Arctic amplification have been carried out in spring 2019 and late summer 2020 over the Fram Strait northwest of Svalbard. The latter campaign was closely connected to the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. Comprehensive datasets of the cloudy Arctic atmosphere have been collected by operating remote sensing instruments, in-situ probes, instruments for the measurement of turbulent fluxes of energy and momentum, and dropsondes on board the AWI research aircraft Polar 5. In total, 24 flights with 111 flight hours have been performed over open ocean, the marginal sea ice zone, and sea ice. The datasets follow documented methods and quality assurance and are suited for studies on Arctic mixed-phase clouds and their transformation processes, for studies with a focus on Arctic boundary layer processes, and for satellite validation applications. All datasets are freely available via the world data center PANGAEA., (© 2022. The Author(s).)

Published
2022
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10. Testing the feasibility and safety of the Nintendo Wii gaming console in orthopedic rehabilitation: a pilot randomized controlled study.

Author

Ficklscherer A, Stapf J, Meissner KM, Niethammer T, Lahner M, Wagenhäuser M, Müller PE, and Pietschmann MF

Abstract

Introduction: The Nintendo Wii game console is already used as an additional training device for e.g. neurological wards. Still there are limited data available regarding orthopedic rehabilitation. The authors' objective was to examine whether the Nintendo Wii is an appropriate and safe tool in rehabilitation after orthopedic knee surgery., Material and Methods: A prospective, randomized, controlled study comparing standard physiotherapy vs. standard physiotherapy plus game console training (Wii group) in patients having anterior cruciate ligament (ACL) repair or knee arthroplasty was conducted. The subjects of the Wii group ( n = 17; mean age: 54 ±19 years) performed simple knee exercises daily under the supervision of a physiotherapist in addition to the normal rehabilitation program. The patients of the control group ( n = 13; 52 ±18 years) were treated with physiotherapy only. The participants of both groups completed a questionnaire including the International Knee Documentation Committee (IKDC) score, the Modified Cincinnati Rating System and the Tegner Lysholm Knee Score prior to the operation, before discharge from hospital and four weeks after treatment., Results: There was no significant difference in the score results between the Wii and the control group ( p > 0.05)., Conclusions: We demonstrated that physiotherapy using the Nintendo Wii gaming console after ACL reconstruction and knee arthroplasty does not negatively influence outcome. Because training with the Wii device was highly accepted by patients, we see an opportunity whereby additional training with a gaming console for a longer period of time could lead to even better results, regarding the training motivation and the outcome after orthopedic surgery., Competing Interests: The authors declare no conflict of interest.

Published
2016
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11. Blood culture Gram stain and simple clinical categorisation can be used to identify patients at risk for delay in appropriate antibiotic treatment.

Author

Veijola S, Burtonwood M, Stapf J, Kauma H, Kauppila J, Koskela M, and Hautala T

Subjects
Bacteremia blood, Community-Acquired Infections drug therapy, Community-Acquired Infections microbiology, Fungemia blood, Fungemia drug therapy, Fungemia microbiology, Gram-Negative Bacterial Infections drug therapy, Gram-Negative Bacterial Infections microbiology, Gram-Positive Bacterial Infections drug therapy, Gram-Positive Bacterial Infections microbiology, Humans, Staining and Labeling, Anti-Bacterial Agents therapeutic use, Bacteremia drug therapy, Bacteremia microbiology, Bacteria classification
Published
2008
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