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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

3. Marine carbohydrates in the Arctic- from the ocean to the atmosphere

Author

Zeppenfeld, S., van Pinxteren, M., Hartmann, S., Wex, H., and Herrmann, H.

Abstract

Marine carbohydrates are produced by microbes in the ocean and contribute significantly to dissolved and particulate organic carbon in the seawater. Recent studies showed that the carbohydrates released by Arctic microorganisms exhibit an extraordinarily high ice nucleating activity making them potentially important ice nucleating particles (INP). These carbohydrates enter the atmosphere as part of sea spray aerosol (SSA) through wind-driven processes and eventually contribute to cloud formation processes. However, the emission processes of marine carbohydrates and their atmospheric aging are still not well understood. Here, we present marine carbohydrates found in bulk seawater (at 1m depth), the sea surface microlayer (SML), size-resolved aerosol particles and fog water collected in the Arctic during the PASCAL/SiPCA cruise (May-July 2017). Chemical and statistical analyses revealed a chemo-selective transfer of carbohydrates towards sodium during the sea-air transfer. Additionally, strong evidence could be found for bacterial modifications of the aerosolized carbohydrates in the atmosphere after their oceanic emission causing quick aging. Finally, we present the influence of sea ice on the sea-air transfer by forming different sea ice related environments, such as the marginal ice zone, open leads, melt ponds and the ice-free ocean with different biological activities and wind conditions.As a consequence of the retreat of sea ice enhanced by Arctic amplification, these processes may lead to a changing availability of potential INP influencing the cloud formation and their microphysical properties., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023
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4. Leakage Rates of Refrigerants CFC-12, HCFC-22, and HFC-134a from Operating Mobile Air Conditioning Systems in Guangzhou, China: Tests inside a Busy Urban Tunnel under Hot and Humid Weather Conditions

Author

van Pinxteren, M., Fomba, K., Triesch, N., Stolle, C., Wurl, O., Bahlmann, E., Gong, X., Voigtlaender, J., Wex, H., Robinson, T., Barthel, S., Zeppenfeld, S., Hoffmann, E., Roveretto, M., Li, C., Grosselin, B., Daele, V., Senf, F., van Pinxteren, D., Manzi, M., Zabalegui, N., Frka, S., Gasparovic, B., Pereira, R., Li, T., Wen, L., Li, J., Zhu, C., Chen, H., Chen, J., Fiedler, B., Von Tuempling, W., Read, K., Punjabi, S., Lewis, A., Hopkins, J., Carpenter, L., Peeken, I., Rixen, T., Schulz-Bull, D., Monge, M., Mellouki, A., George, C., Stratmann, F., Herrmann, H., Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut des Sciences de l'Ingénierie et des Systèmes (INSIS), IRCELYON-Catalytic and Atmospheric Reactivity for the Environment (CARE), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), European Project: 690958,H2020,H2020-MSCA-RISE-2015,MARSU(2016), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
Engineering, South china, 010504 meteorology & atmospheric sciences, Ecology, Waste management, business.industry, Health, Toxicology and Mutagenesis, Environmental engineering, [CHIM.CATA]Chemical Sciences/Catalysis, 010501 environmental sciences, [SDE.ES]Environmental Sciences/Environmental and Society, 7. Clean energy, 01 natural sciences, Pollution, Refrigerant, 13. Climate action, Air conditioning, 11. Sustainability, Environmental Chemistry, business, Waste Management and Disposal, Hot and humid, 0105 earth and related environmental sciences, Water Science and Technology, Leakage (electronics)
Abstract

SSCI-VIDE+CARE+CGO:XWG; International audience; Determining the leakage rates of halogenated refrigerants from operating mobile air conditioning systems (MACs) is a challenging task. Here, we take advantage of a heavily trafficked tunnel with a traffic flow of over 40,000 motor vehicles per day in south China. We carried out measurements in 2014 on hot and humid days, and therefore, it is reasonable to assume that essentially all of the MAC units would be turned on to ensure the thermo-comfort of the occupants. Thus, we obtained the leakage rates of the three most important refrigerants from the operating MACs aboard the on-road vehicles. The emission factors (EFs) of HFC-134a, HCFC-22, and CFC-12 from the on-road operating MACs are 1.27 ± 0.11, 0.47 ± 0.04, and 0.17 ± 0.04 mg km −1 veh −1 , respectively. Normalized by the percentages of vehicles using different refrigerants in their MACs, the emission rates of HFC-134a, HCFC-22, and CFC-12 are 52.2, 329, and 59.5 mg h −1 veh −1 , respectively. This emission rate of HFC-134a is approximately 10 times higher than those previously reported in Europe for stationary conditions and a whole-lifetime average of fugitive losses. The unusually high leakage rates suggest that improving the leak tightness of MACs in China would help to greatly lower their emissions. The global warming potentials associated with refrigerant leakage is equal to 1.4% of the CO 2 directly emitted due to fuel consumptions.

Published
2017
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5. Marine organic matter in the remote environment of the Cape Verde islands – an introduction and overview to the MarParCloud campaign

Author

van Pinxteren, M., Wadinga Fomba, K., Triesch, N., Stolle, C., Wurl, O., Bahlmann, E., Gong, X., Voigtländer, J., Wex, H., Robinson, T.-B., Barthel, S., Zeppenfeld, S., Hoffmann, E.H., Roveretto, M., Li, C., Grosselin, B., Daële, V., Senf, F., van Pinxteren, D., Manzi, M., Zabalegui, N., Frka, S., Gašparović, B., Pereira, R., Li, T., Wen, L., Li, J., Zhu, C., Chen, H., Chen, J., Fiedler, B., von Tümpling, Wolf, Read, K.A., Punjabi, S., Lewis, A.C.C., Hopkins, J.R., Carpenter, L.J., Peeken, I., Rixen, T., Schulz-Bull, D., Monge, M.E., Mellouki, A., George, C., Stratmann, F., Herrmann, H., van Pinxteren, M., Wadinga Fomba, K., Triesch, N., Stolle, C., Wurl, O., Bahlmann, E., Gong, X., Voigtländer, J., Wex, H., Robinson, T.-B., Barthel, S., Zeppenfeld, S., Hoffmann, E.H., Roveretto, M., Li, C., Grosselin, B., Daële, V., Senf, F., van Pinxteren, D., Manzi, M., Zabalegui, N., Frka, S., Gašparović, B., Pereira, R., Li, T., Wen, L., Li, J., Zhu, C., Chen, H., Chen, J., Fiedler, B., von Tümpling, Wolf, Read, K.A., Punjabi, S., Lewis, A.C.C., Hopkins, J.R., Carpenter, L.J., Peeken, I., Rixen, T., Schulz-Bull, D., Monge, M.E., Mellouki, A., George, C., Stratmann, F., and Herrmann, H.

Abstract

The project MarParCloud (Marine biological production, organic aerosol Particles and marine Clouds: a process chain) aims at improving our understanding of the genesis, modification and impact of marine organic matter (OM), from its biological production, via its export to marine aerosol particles and, finally, towards its ability to act as ice nucleating particles (INP) and cloud condensation nuclei (CCN). A field campaign at the Cape Verde Atmospheric Observatory (CVAO) in the tropics in September/October 2017 formed the core of this project that was jointly performed with the project (MARine atmospheric Science Unravelled). A suite of chemical, physical, biological and meteorological techniques was applied and comprehensive measurements of bulk water, the sea surface microlayer (SML), cloud water and ambient aerosol particles collected at a ground-based and a mountain station took place. Key variables comprised the chemical characterization of the atmospherically relevant OM components in the ocean and the atmosphere as well as measurements of INP and CCN. Moreover, bacterial cell counts, mercury species and trace gases were analysed. To interpret the results, the measurements were accompanied by various auxiliary parameters such as air mass back trajectory analysis, vertical atmospheric profile analysis, cloud observations and pigment measurements in seawater. Additional modelling studies supported the experimental analysis. During the campaign, the CVAO exhibited marine air masses with low and partly moderate dust influences. The marine boundary layer was well mixed as indicated by an almost uniform particle number size distribution within the boundary layer. Lipid biomarkers were present in the aerosol particles in typical concentrations of marine background conditions. Accumulation and coarse mode particles served as CCN and were efficiently transferred to the cloud water. The ascent of ocean-derived compounds, such as sea salt and sugar-like compounds, to th

Published
2020

6. Glucose as a potential chemical marker for ice nucleating activity in Arctic seawater samples.

Author

Zeppenfeld, S., von Pnxteren, M., Hartmann, M., Bracher, Astrid, Stratmann, F., Herrmann, H., Zeppenfeld, S., von Pnxteren, M., Hartmann, M., Bracher, Astrid, Stratmann, F., and Herrmann, H.

Abstract

Recent studies pointed to a high ice nucleating activity (INA) in the Arctic sea surface microlayer (SML). However, related chemical information is still sparse. In the present study, INA and free glucose concentrations were quantified in Arctic SML and bulk water samples from the marginal ice zone, the ice-free ocean, melt ponds, and open waters within the ice pack. T50 (defining INA) ranged from −17.4 to −26.8 °C. Glucose concentrations varied from 0.6 to 51 μg/L with highest values in the SML from the marginal ice zone and melt ponds (median 16.3 and 13.5 μg/L) and lower values in the SML from the ice pack and the ice-free ocean (median 3.9 and 4.0 μg/L). Enrichment factors between the SML and the bulk ranged from 0.4 to 17. A positive correlation was observed between free glucose concentration and INA in Arctic water samples (T50(°C) = (−25.6 ± 0.6) + (0.15 ± 0.04)·Glucose(μg/L), RP = 0.66, n = 74). Clustering water samples based on phytoplankton pigment composition resulted in robust but different correlations within the four clusters (RP between 0.67 and 0.96), indicating a strong link to phytoplankton-related processes. Since glucose did not show significant INA itself, free glucose may serve as a potential tracer for INA in Arctic water samples.

Published
2019

7. Rapid growth of Aitken-mode particles during Arctic summer by fog chemical processing and its implication.

Author

Kecorius S, Hoffmann EH, Tilgner A, Barrientos-Velasco C, van Pinxteren M, Zeppenfeld S, Vogl T, Madueño L, Lovrić M, Wiedensohler A, Kulmala M, Paasonen P, and Herrmann H

Abstract

In the Arctic, new particle formation (NPF) and subsequent growth processes are the keys to produce Aitken-mode particles, which under certain conditions can act as cloud condensation nuclei (CCNs). The activation of Aitken-mode particles increases the CCN budget of Arctic low-level clouds and, accordingly, affects Arctic climate forcing. However, the growth mechanism of Aitken-mode particles from NPF into CCN range in the summertime Arctic boundary layer remains a subject of current research. In this combined Arctic cruise field and modeling study, we investigated Aitken-mode particle growth to sizes above 80 nm. A mechanism is suggested that explains how Aitken-mode particles can become CCN without requiring high water vapor supersaturation. Model simulations suggest the formation of semivolatile compounds, such as methanesulfonic acid (MSA) in fog droplets. When the fog droplets evaporate, these compounds repartition from CCNs into the gas phase and into the condensed phase of nonactivated Aitken-mode particles. For MSA, a mass increase factor of 18 is modeled. The postfog redistribution mechanism of semivolatile acidic and basic compounds could explain the observed growth of >20 nm h -1 for 60-nm particles to sizes above 100 nm. Overall, this study implies that the increasing frequency of NPF and fog-related particle processing can affect Arctic cloud properties in the summertime boundary layer., (© The Author(s) 2023. Published by Oxford University Press on behalf of National Academy of Sciences.)

Published
2023
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