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2. Variability and change in the west Antarctic Peninsula marine system: Research priorities and opportunities

Author

Henley, Sian F, Schofield, Oscar M, Hendry, Katharine R, Schloss, Irene R, Steinberg, Deborah K, Moffat, Carlos, Peck, Lloyd S, Costa, Daniel P, Bakker, Dorothee CE, Hughes, Claire, Rozema, Patrick D, Ducklow, Hugh W, Abele, Doris, Stefels, Jacqueline, Van Leeuwe, Maria A, Brussaard, Corina PD, Buma, Anita GJ, Kohut, Josh, Sahade, Ricardo, Friedlaender, Ari S, Stammerjohn, Sharon E, Venables, Hugh J, and Meredith, Michael P

Subjects
Life Below Water, Climate Action, Physical oceanography, Nutrient and carbon cycling, Ecosystems, Primary production, Sea ice, Climate change, Geology, Oceanography
Published
2019

4. Overview of the MOSAiC expedition: Ecosystem

Author

Fong, Allison A., Hoppe, Clara J. M., Aberle, Nicole, Ashjian, Carin J., Assmy, Philipp, Bai, Youcheng, Bakker, Dorothee C. E., Balmonte, John P., Barry, Kevin R., Bertilsson, Stefan, Boulton, William, Bowman, Jeff, Bozzato, Deborah, Bratbak, Gunnar, Buck, Moritz, Campbell, Robert G., Castellani, Giulia, Chamberlain, Emelia J., Chen, Jianfang, Chierici, Melissa, Cornils, Astrid, Creamean, Jessie M., Damm, Ellen, Dethloff, Klaus, Droste, Elise S., Ebenhöh, Oliver, Eggers, Sarah L., Engel, Anja, Flores, Hauke, Fransson, Agneta, Frickenhaus, Stephan, Gardner, Jessie, Gelfman, Cecilia E., Granskog, Mats A., Graeve, Martin, Havermans, Charlotte, Heuzé, Céline, Hildebrandt, Nicole, Hill, Thomas C. J., Hoppema, Mario, Immerz, Antonia, Jin, Haiyan, Koch, Boris P., Kong, Xianyu, Kraberg, Alexandra, Lan, Musheng, Lange, Benjamin A., Larsen, Aud, Lebreton, Benoit, Leu, Eva, Loose, Brice, Maslowski, Wieslaw, Mavis, Camille, Metfies, Katja, Mock, Thomas, Müller, Oliver, Nicolaus, Marcel, Niehoff, Barbara, Nomura, Daiki, Nöthig, Eva-Maria, Oggier, Marc, Oldenburg, Ellen, Olsen, Lasse Mork, Peeken, Ilka, Perovich, Donald K., Popa, Ovidiu, Rabe, Benjamin, Ren, Jian, Rex, Markus, Rinke, Annette, Rokitta, Sebastian, Rost, Björn, Sakinan, Serdar, Salganik, Evgenii, Schaafsma, Fokje L., Schäfer, Hendrik, Schmidt, Katrin, Shoemaker, Katyanne M., Shupe, Matthew D., Snoeijs-Leijonmalm, Pauline, Stefels, Jacqueline, Svenson, Anders, Tao, Ran, Torres-Valdés, Sinhué, Torstensson, Anders, Toseland, Andrew, Ulfsbo, Adam, Van Leeuwe, Maria A., Vortkamp, Martina, Webb, Alison L., Zhuang, Yanpei, Gradinger, Rolf R., Fong, Allison A., Hoppe, Clara J. M., Aberle, Nicole, Ashjian, Carin J., Assmy, Philipp, Bai, Youcheng, Bakker, Dorothee C. E., Balmonte, John P., Barry, Kevin R., Bertilsson, Stefan, Boulton, William, Bowman, Jeff, Bozzato, Deborah, Bratbak, Gunnar, Buck, Moritz, Campbell, Robert G., Castellani, Giulia, Chamberlain, Emelia J., Chen, Jianfang, Chierici, Melissa, Cornils, Astrid, Creamean, Jessie M., Damm, Ellen, Dethloff, Klaus, Droste, Elise S., Ebenhöh, Oliver, Eggers, Sarah L., Engel, Anja, Flores, Hauke, Fransson, Agneta, Frickenhaus, Stephan, Gardner, Jessie, Gelfman, Cecilia E., Granskog, Mats A., Graeve, Martin, Havermans, Charlotte, Heuzé, Céline, Hildebrandt, Nicole, Hill, Thomas C. J., Hoppema, Mario, Immerz, Antonia, Jin, Haiyan, Koch, Boris P., Kong, Xianyu, Kraberg, Alexandra, Lan, Musheng, Lange, Benjamin A., Larsen, Aud, Lebreton, Benoit, Leu, Eva, Loose, Brice, Maslowski, Wieslaw, Mavis, Camille, Metfies, Katja, Mock, Thomas, Müller, Oliver, Nicolaus, Marcel, Niehoff, Barbara, Nomura, Daiki, Nöthig, Eva-Maria, Oggier, Marc, Oldenburg, Ellen, Olsen, Lasse Mork, Peeken, Ilka, Perovich, Donald K., Popa, Ovidiu, Rabe, Benjamin, Ren, Jian, Rex, Markus, Rinke, Annette, Rokitta, Sebastian, Rost, Björn, Sakinan, Serdar, Salganik, Evgenii, Schaafsma, Fokje L., Schäfer, Hendrik, Schmidt, Katrin, Shoemaker, Katyanne M., Shupe, Matthew D., Snoeijs-Leijonmalm, Pauline, Stefels, Jacqueline, Svenson, Anders, Tao, Ran, Torres-Valdés, Sinhué, Torstensson, Anders, Toseland, Andrew, Ulfsbo, Adam, Van Leeuwe, Maria A., Vortkamp, Martina, Webb, Alison L., Zhuang, Yanpei, and Gradinger, Rolf R.

Abstract

The international and interdisciplinary sea-ice drift expedition “The Multidisciplinary drifting Observatory for the Study of Arctic Climate” (MOSAiC) was conducted from October 2019 to September 2020. The aim of MOSAiC was to study the interconnected physical, chemical, and biological characteristics and processes from the atmosphere to the deep sea of the central Arctic system. The ecosystem team addressed current knowledge gaps and explored unknown biological properties over a complete seasonal cycle focusing on three major research areas: biodiversity, biogeochemical cycles, and linkages to the environment. In addition to the measurements of core properties along a complete seasonal cycle, dedicated projects covered specific processes and habitats, or organisms on higher taxonomic or temporal resolution in specific time windows. A wide range of sampling instruments and approaches, including sea-ice coring, lead sampling with pumps, rosette-based water sampling, plankton nets, remotely operated vehicles, and acoustic buoys, was applied to address the science objectives. Further, a broad range of process-related measurements to address, for example, productivity patterns, seasonal migrations, and diversity shifts, were made both in situ and onboard RV Polarstern. This article provides a detailed overview of the sampling approaches used to address the three main science objectives. It highlights the core sampling program and provides examples of habitat- or process-specific sampling. The initial results presented include high biological activities in wintertime and the discovery of biological hotspots in underexplored habitats. The unique interconnectivity of the coordinated sampling efforts also revealed insights into cross-disciplinary interactions like the impact of biota on Arctic cloud formation. This overview further presents both lessons learned from conducting such a demanding field campaign and an outlook on spin-off projects to be conducted over the next

Published
2024
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5. The future of Arctic sea-ice biogeochemistry and ice-associated ecosystems

Author

Lannuzel, Delphine, Tedesco, Letizia, van Leeuwe, Maria, Campbell, Karley, Flores, Hauke, Delille, Bruno, Miller, Lisa, Stefels, Jacqueline, Assmy, Philipp, Bowman, Jeff, Brown, Kristina, Castellani, Giulia, Chierici, Melissa, Crabeck, Odile, Damm, Ellen, Else, Brent, Fransson, Agneta, Fripiat, François, Geilfus, Nicolas-Xavier, Jacques, Caroline, Jones, Elizabeth, Kaartokallio, Hermanni, Kotovitch, Marie, Meiners, Klaus, Moreau, Sébastien, Nomura, Daiki, Peeken, Ilka, Rintala, Janne-Markus, Steiner, Nadja, Tison, Jean-Louis, Vancoppenolle, Martin, Van der Linden, Fanny, Vichi, Marcello, and Wongpan, Pat

Published
2020
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6. Variability and change in the west Antarctic Peninsula marine system: Research priorities and opportunities

Author

Henley, Sian F., Schofield, Oscar M., Hendry, Katharine R., Schloss, Irene R., Steinberg, Deborah K., Moffat, Carlos, Peck, Lloyd S., Costa, Daniel P., Bakker, Dorothee C.E., Hughes, Claire, Rozema, Patrick D., Ducklow, Hugh W., Abele, Doris, Stefels, Jacqueline, Van Leeuwe, Maria A., Brussaard, Corina P.D., Buma, Anita G.J., Kohut, Josh, Sahade, Ricardo, Friedlaender, Ari S., Stammerjohn, Sharon E., Venables, Hugh J., and Meredith, Michael P.

Published
2019
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10. Evolving research directions in Surface Ocean–Lower Atmosphere (SOLAS) science

Author

Law, Cliff S, Brévière, Emilie, de Leeuw, Gerrit, Garçon, Véronique, Guieu, Cécile, Kieber, David J, Kontradowitz, Stefan, Paulmier, Aurélien, Quinn, Patricia K, Saltzman, Eric S, Stefels, Jacqueline, and von Glasow, Roland

Subjects
Climate Action, Life Below Water, Chemical Sciences, Earth Sciences, Environmental Sciences
Abstract

This review focuses on critical issues in ocean-atmosphere exchange that will be addressed by new research strategies developed by the international Surface Ocean-Lower Atmosphere Study (SOLAS) research community. Eastern boundary upwelling systems are important sites for CO2 and trace gas emission to the atmosphere, and the proposed research will examine how heterotrophic processes in the underlying oxygen-deficient waters interact with the climate system. The second regional research focus will examine the role of sea-ice biogeochemistry and its interaction with atmospheric chemistry. Marine aerosols are the focus of a research theme directed at understanding the processes that determine their abundance, chemistry and radiative properties. A further area of aerosol-related research examines atmospheric nutrient deposition in the surface ocean, and how differences in origin, atmospheric processing and composition influence surface ocean biogeochemistry. Ship emissions are an increasing source of aerosols, nutrients and toxins to the atmosphere and ocean surface, and an emerging area of research will examine their effect on ocean biogeochemistry and atmospheric chemistry. The primary role of SOLAS is to coordinate coupled multi-disciplinary research within research strategies that address these issues, to achieve robust representation of critical ocean-atmosphere exchange processes in Earth System models. © 2013 CSIRO.

Published
2013

16. Thin and transient meltwater layers and false bottoms in the Arctic sea ice pack—Recent insights on these historically overlooked features

Author

Smith, Madison M, Angot, Hélène, Chamberlain, Emelia J, Droste, Elise S, Karam, Salar, Muilwijk, Morven, Webb, Alison L, Archer, Stephen D, Beck, Ivo, Blomquist, Byron W, Bowman, Jeff, Boyer, Matthew, Bozzato, Deborah, Chierici, Melissa, Creamean, Jessie, D’Angelo, Alessandra, Delille, Bruno, Fer, Ilker, Fong, Allison A, Fransson, Agneta, Fuchs, Niels, Gardner, Jessie, Granskog, Mats A, Hoppe, Clara JM, Hoppema, Mario, Hoppmann, Mario, Mock, Thomas, Muller, Sofia, Müller, Oliver, Nicolaus, Marcel, Nomura, Daiki, Petäjä, Tuukka, Salganik, Evgenii, Schmale, Julia, Schmidt, Katrin, Schulz, Kirstin M, Shupe, Matthew D, Stefels, Jacqueline, Thielke, Linda, Tippenhauer, Sandra, Ulfsbo, Adam, van Leeuwe, Maria, Webster, Melinda, Yoshimura, Masaki, Zhan, Liyang, Smith, Madison M, Angot, Hélène, Chamberlain, Emelia J, Droste, Elise S, Karam, Salar, Muilwijk, Morven, Webb, Alison L, Archer, Stephen D, Beck, Ivo, Blomquist, Byron W, Bowman, Jeff, Boyer, Matthew, Bozzato, Deborah, Chierici, Melissa, Creamean, Jessie, D’Angelo, Alessandra, Delille, Bruno, Fer, Ilker, Fong, Allison A, Fransson, Agneta, Fuchs, Niels, Gardner, Jessie, Granskog, Mats A, Hoppe, Clara JM, Hoppema, Mario, Hoppmann, Mario, Mock, Thomas, Muller, Sofia, Müller, Oliver, Nicolaus, Marcel, Nomura, Daiki, Petäjä, Tuukka, Salganik, Evgenii, Schmale, Julia, Schmidt, Katrin, Schulz, Kirstin M, Shupe, Matthew D, Stefels, Jacqueline, Thielke, Linda, Tippenhauer, Sandra, Ulfsbo, Adam, van Leeuwe, Maria, Webster, Melinda, Yoshimura, Masaki, and Zhan, Liyang

Abstract

The rapid melt of snow and sea ice during the Arctic summer provides a significant source of low-salinity meltwater to the surface ocean on the local scale. The accumulation of this meltwater on, under, and around sea ice floes can result in relatively thin meltwater layers in the upper ocean. Due to the small-scale nature of these upper-ocean features, typically on the order of 1 m thick or less, they are rarely detected by standard methods, but are nevertheless pervasive and critically important in Arctic summer. Observations during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in summer 2020 focused on the evolution of such layers and made significant advancements in understanding their role in the coupled Arctic system. Here we provide a review of thin meltwater layers in the Arctic, with emphasis on the new findings from MOSAiC. Both prior and recent observational datasets indicate an intermittent yet longlasting (weeks to months) meltwater layer in the upper ocean on the order of 0.1 m to 1.0 m in thickness, with a large spatial range. The presence of meltwater layers impacts the physical system by reducing bottom ice melt and allowing new ice formation via false bottom growth. Collectively, the meltwater layer and false bottoms reduce atmosphere-ocean exchanges of momentum, energy, and material.The impacts on the coupled Arctic system are far-reaching, including acting as a barrier for nutrient and gas exchange and impacting ecosystem diversity and productivity.

Published
2023

17. An international circumpolar compilation of macronutrient concentrations in Antarctic land-fast sea ice: science highlights and open access data

Author

Southern Ocean Observing System Symposium (14-18 August 2023: Hobart, Australia), Henley, Sian S.F., Cozzi, Stefano, Fripiat, François, Lannuzel, Delphine, Nomura, Daïki, Thomas, David D.N., Meiners, Klaus Martin, Vancoppenolle, Martin, Arrigo, Kevin K.R., Stefels, Jacqueline, Van Leeuwe, Maria M.A., Moreau, Sébastien, Jones, Elisabeth, Fransson, Agneta A.F., Chierici, Melissa M.C., Delille, B., Southern Ocean Observing System Symposium (14-18 August 2023: Hobart, Australia), Henley, Sian S.F., Cozzi, Stefano, Fripiat, François, Lannuzel, Delphine, Nomura, Daïki, Thomas, David D.N., Meiners, Klaus Martin, Vancoppenolle, Martin, Arrigo, Kevin K.R., Stefels, Jacqueline, Van Leeuwe, Maria M.A., Moreau, Sébastien, Jones, Elisabeth, Fransson, Agneta A.F., Chierici, Melissa M.C., and Delille, B.

Abstract

info:eu-repo/semantics/nonPublished

Published
2023

18. Establishing an International, Multidisciplinary Community of Practice for the Study of Methylated Sulfur Compounds in the Ocean: SCOR Working Group DMS-Pro

Author

Galí, Martí, del Valle, Daniela A., Archer, Steve D., Bange, Hermann, Bucciarelli, Eva, Deschaseaux, Elisabeth, González, José M., Hayashida, Hakase, Hopkins, Frances, Kameyama, Sohiko, McParland, Erin, Park, Ki-Tae, Shenoy, Damodar, Stefels, Jacqueline, Todd, Jonathan, Tortell, Philippe, Winkel, Lenny, Yang, Gui-Peng, Zárate, Marcos, Zhang, Miming, Galí, Martí, del Valle, Daniela A., Archer, Steve D., Bange, Hermann, Bucciarelli, Eva, Deschaseaux, Elisabeth, González, José M., Hayashida, Hakase, Hopkins, Frances, Kameyama, Sohiko, McParland, Erin, Park, Ki-Tae, Shenoy, Damodar, Stefels, Jacqueline, Todd, Jonathan, Tortell, Philippe, Winkel, Lenny, Yang, Gui-Peng, Zárate, Marcos, and Zhang, Miming

Abstract

Organic methylated sulfur compounds (MSCs) play key roles in marine planktonic food webs and are also involved in climate regulation through the emission of aerosol-forming gases (dimethylsulfide and methanethiol). Therefore, the study of MSCs naturally bridges a wide range of disciplines, from molecular ecology, through oceanography, up to Earth System modelling. In 2022, a new SCOR Working Group named DMS-PRO was created to address knowledge gaps in MSC research by (i) compiling an open-access database of MSC cycling rates; (ii) publishing standardized operating practices for the determination of MSC cycling rates; and (iii) providing guidance to data users, e.g. modelers. DMS-PRO nucleates 20 researchers from 14 countries in Asia, North and South America, Oceania, and Europe; including 6 members from low- and upper-middle income countries and 6 early-career researchers. Forming a group with a balanced geographic spread was challenging because researchers focusing in this area of study are overwhelmingly associated to institutions based in developed countries. To reduce this imbalance, an overarching aspiration of DMS-PRO is to stimulate research, build capacity, and establish an international, multidisciplinary community of practice on the oceanic cycle of MSCs that can share knowledge and skills with the broader oceanographic and Earth system science communities. In this presentation we will briefly introduce DMS-PRO, share the lessons learned during the initial phase of the project, and outline our plans for achieving the group’s objectives

Published
2023

21. Critically important, yet forgotten: thin and transient meltwater layers and false bottoms in the Arctic sea ice pack

Author

Smith, Madison M., Angot, Helene, Chamberlain, Emelia J., Droste, Elise, Karam, Salar, Muilwijk, Morven, Webb, Alison, Archer, Stephen, Beck, Ivo, Blomquist, Byron, Bowman, Jeff, Boyer, Matthew, Bozzato, Deborah, Chierici, Melissa, Creamean, Jessie, D'Angelo, Alessandra, Delille, Bruno, Fer, Ilker, Fong, Allison A., Fransson, Agneta, Fuchs, Niels, Gardner, Jessie, Granskog, Mats A., Hoppe, Clara J. M., Hoppema, Mario, Hoppmann, Mario, Mock, Thomas, Muller, Sofia, Müller, Oliver, Nicolaus, Marcel, Nomura, Daiki, Petäjä, Tuukka, Salganik, Evgenii, Schmale, Julia, Schmidt, Katrin, Schulz, Kirstin, Shupe, Matthew D., Stefels, Jacqueline, Thielke, Linda, Tippenhauer, Sandra, Ulfsbo, Adam, van Leeuwe, Maria, Webster, Melinda, Yoshimura, Masaki, and Zhan, Liyang

Subjects
Arctic, meltwater, interdisciplinary science, sea ice
Abstract

The rapid melt of snow and sea ice during the Arctic summer provides a significant source of low-salinity meltwater to the surface ocean on the local scale. The accumulation of this meltwater on, under, and around sea ice floes can result in relatively thin meltwater layers in the upper ocean. Due to the small-scale nature of these upper-ocean features, typically on the order of 1 m thick or less, they are rarely detected by standard methods, but are nevertheless pervasive and critically important in Arctic summer. Observations during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition in summer 2020 focused on the evolution of such layers and made significant advancements in understanding their role in the coupled Arctic system. Here we provide a review of thin meltwater layers in the Arctic, with emphasis on the new findings from MOSAiC. Both prior and recent observational datasets indicate an intermittent yet long-lasting (weeks to months) meltwater layer in the upper ocean on the order of 0.1 to 1.0 m in thickness, with a large spatial range. The presence of meltwater layers impacts the physical system by reducing bottom ice melt and allowing new ice formation via false bottom growth. Collectively, the meltwater layer and false bottoms reduce atmosphere-ocean exchanges of momentum, energy, and material. The impacts on the coupled Arctic system are far-reaching, including acting as a barrier for nutrient and gas exchange and impacting ecosystem diversity and productivity.

Published
2023
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22. Short-Lived Trace Gases in the Surface Ocean and the Atmosphere

Author

Liss, Peter S., Marandino, Christa A., Dahl, Elizabeth E., Helmig, Detlev, Hintsa, Eric J., Hughes, Claire, Johnson, Martin T., Moore, Robert M., Plane, John M. C., Quack, Birgit, Singh, Hanwant B., Stefels, Jacqueline, von Glasow, Roland, Williams, Jonathan, Liss, Peter S., editor, and Johnson, Martin T., editor

Published
2014
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23. Thin and transient meltwater layers and false bottoms in the Arctic sea ice pack—Recent insights on these historically overlooked features

Author

Smith, Madison M., primary, Angot, Hélène, additional, Chamberlain, Emelia J., additional, Droste, Elise S., additional, Karam, Salar, additional, Muilwijk, Morven, additional, Webb, Alison L., additional, Archer, Stephen D., additional, Beck, Ivo, additional, Blomquist, Byron W., additional, Bowman, Jeff, additional, Boyer, Matthew, additional, Bozzato, Deborah, additional, Chierici, Melissa, additional, Creamean, Jessie, additional, D’Angelo, Alessandra, additional, Delille, Bruno, additional, Fer, Ilker, additional, Fong, Allison A., additional, Fransson, Agneta, additional, Fuchs, Niels, additional, Gardner, Jessie, additional, Granskog, Mats A., additional, Hoppe, Clara J. M., additional, Hoppema, Mario, additional, Hoppmann, Mario, additional, Mock, Thomas, additional, Muller, Sofia, additional, Müller, Oliver, additional, Nicolaus, Marcel, additional, Nomura, Daiki, additional, Petäjä, Tuukka, additional, Salganik, Evgenii, additional, Schmale, Julia, additional, Schmidt, Katrin, additional, Schulz, Kirstin M., additional, Shupe, Matthew D., additional, Stefels, Jacqueline, additional, Thielke, Linda, additional, Tippenhauer, Sandra, additional, Ulfsbo, Adam, additional, van Leeuwe, Maria, additional, Webster, Melinda, additional, Yoshimura, Masaki, additional, and Zhan, Liyang, additional

Published
2023
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28. Deciphering the Properties of Different Arctic Ice Types During the Growth Phase of MOSAiC: Implications for Future Studies on Gas Pathways

Author

Angelopoulos, Michael, primary, Damm, Ellen, additional, Simões Pereira, Patric, additional, Abrahamsson, Katarina, additional, Bauch, Dorothea, additional, Bowman, Jeff, additional, Castellani, Giulia, additional, Creamean, Jessie, additional, Divine, Dmitry V., additional, Dumitrascu, Adela, additional, Fons, Steven W., additional, Granskog, Mats A., additional, Kolabutin, Nikolai, additional, Krumpen, Thomas, additional, Marsay, Chris, additional, Nicolaus, Marcel, additional, Oggier, Marc, additional, Rinke, Annette, additional, Sachs, Torsten, additional, Shimanchuk, Egor, additional, Stefels, Jacqueline, additional, Stephens, Mark, additional, Ulfsbo, Adam, additional, Verdugo, Josefa, additional, Wang, Lei, additional, Zhan, Liyang, additional, and Haas, Christian, additional

Published
2022
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31. Species-Level Differences in Osmoprotectants and Antioxidants Contribute to Stress Tolerance of Quercus robur L., and Q. cerris L. Seedlings under Water Deficit and High Temperatures

Author

Kebert, Marko, primary, Vuksanović, Vanja, additional, Stefels, Jacqueline, additional, Bojović, Mirjana, additional, Horák, Rita, additional, Kostić, Saša, additional, Kovačević, Branislav, additional, Orlović, Saša, additional, Neri, Luisa, additional, Magli, Massimiliano, additional, and Rapparini, Francesca, additional

Published
2022
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32. On the phenology and seeding potential of sea-ice microalgal species

Author

van Leeuwe, Maria A., Fenton, Mairi, Davey, Emily, Rintala, Jann-Markus, Jones, Elizabeth M., Meredith, Michael P., Stefels, Jacqueline, van Leeuwe, Maria A., Fenton, Mairi, Davey, Emily, Rintala, Jann-Markus, Jones, Elizabeth M., Meredith, Michael P., and Stefels, Jacqueline

Abstract

Sea ice is an important habitat for a wide variety of microalgal species. Depending on the species composition, sea ice can be a seeding source for pelagic phytoplankton blooms after ice melt in spring. Sea-ice algal communities were studied over 2 full winter seasons in 2014 and 2016 at Rothera Research Station, situated at the Western Antarctic Peninsula (WAP). Algal pigment patterns and microscopic observations were combined with photophysiological studies based on fluorescence analyses to monitor and explain the phenology of ice-algal species. Clear patterns in species succession were identified. Young sea ice contained a mixture of algal species including dinoflagellates, cryptophytes and diatoms like Chaetoceros spp. and Fragillariopsis spp. In winter, severe environmental conditions resulted in a decline in species diversity and selection towards heterotrophy. Pennate diatoms like Amphiprora kufferathii and Berkeleya adeliensis were the first to dominate the nutrient-enriched bottom-ice layers in early spring. The bottom communities exhibited a remarkably stable value for the photoadaptation parameter, Ek, of circa 25 µmol photons m–2 s–1. Whereas pennate diatoms were most abundant in spring ice, the initial seeding event linked to ice melt was associated with flagellate species. Haptophyte species like Phaeocystis antarctica and prymnesiophytes like Pyramimonas spp. best sustained the transition from sea ice to seawater. Comparison with previous studies shows that the seeding patterns observed in Ryder Bay were characteristic over the wider sea-ice domain, Arctic and Antarctic. Over the course of this century, the WAP is predicted to experience continuing thinning and decline in sea-ice cover. For the near future, we expect that especially microalgal communities of haptophytes and chlorophytes will benefit from the changes, with yet unknown implications for carbon fluxes and higher trophic levels.

Published
2022

33. Deciphering the Properties of Different Arctic Ice Types During the Growth Phase of MOSAiC: Implications for Future Studies on Gas Pathways

Author

Angelopoulos, Michael, Damm, Ellen, Simões Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Castellani, Giulia, Creamean, Jessie, Divine, Dmitry V., Dumitrascu, Adela, Fons, Steven W., Granskog, Mats A., Kolabutin, Nikolai, Krumpen, Thomas, Marsay, Chris, Nicolaus, Marcel, Oggier, Marc, Rinke, Annette, Sachs, Torsten, Shimanchuk, Egor, Stefels, Jacqueline, Stephens, Mark, Ulfsbo, Adam, Verdugo, Josefa, Wang, Lei, Zhan, Liyang, Haas, Christian, Angelopoulos, Michael, Damm, Ellen, Simões Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Castellani, Giulia, Creamean, Jessie, Divine, Dmitry V., Dumitrascu, Adela, Fons, Steven W., Granskog, Mats A., Kolabutin, Nikolai, Krumpen, Thomas, Marsay, Chris, Nicolaus, Marcel, Oggier, Marc, Rinke, Annette, Sachs, Torsten, Shimanchuk, Egor, Stefels, Jacqueline, Stephens, Mark, Ulfsbo, Adam, Verdugo, Josefa, Wang, Lei, Zhan, Liyang, and Haas, Christian

Abstract

The increased fraction of first year ice (FYI) at the expense of old ice (second-year ice (SYI) and multi-year ice (MYI)) likely affects the permeability of the Arctic ice cover. This in turn influences the pathways of gases circulating therein and the exchange at interfaces with the atmosphere and ocean. We present sea ice temperature and salinity time series from different ice types relevant to temporal development of sea ice permeability and brine drainage efficiency from freeze-up in October to the onset of spring warming in May. Our study is based on a dataset collected during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 and 2020. These physical properties were used to derive sea ice permeability and Rayleigh numbers. The main sites included FYI and SYI. The latter was composed of an upper layer of residual ice that had desalinated but survived the previous summer melt and became SYI. Below this ice a layer of new first-year ice formed. As the layer of new first-year ice has no direct contact with the atmosphere, we call it insulated first-year ice (IFYI). The residual/SYI-layer also contained refrozen melt ponds in some areas. During the freezing season, the residual/SYI-layer was consistently impermeable, acting as barrier for gas exchange between the atmosphere and ocean. While both FYI and SYI temperatures responded similarly to atmospheric warming events, SYI was more resilient to brine volume fraction changes because of its low salinity (< 2). Furthermore, later bottom ice growth during spring warming was observed for SYI in comparison to FYI. The projected increase in the fraction of more permeable FYI in autumn and spring in the coming decades may favor gas exchange at the atmosphere-ice interface when sea ice acts as a source relative to the atmosphere. While the areal extent of old ice is decreasing, so is its thickness at the onset of freeze-up. Our study sets the foundation for studies on gas

Published
2022
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34. Species-Level Differences in Osmoprotectants and Antioxidants Contribute to Stress Tolerance of Quercus robur L., and Q. cerris L. Seedlings under Water Deficit and High Temperatures

Author

Kebert, Marko, Vuksanović, Vanja, Stefels, Jacqueline, Bojović, Mirjana, Horak, Rita, Kostić, Sasa, Kovacević, Branislav, Orlović, Saša, Neri, Luisa, Magli, Massimiliano, Rapparini, Francesca, Kebert, Marko, Vuksanović, Vanja, Stefels, Jacqueline, Bojović, Mirjana, Horak, Rita, Kostić, Sasa, Kovacević, Branislav, Orlović, Saša, Neri, Luisa, Magli, Massimiliano, and Rapparini, Francesca

Abstract

The general aim of this work was to compare the leaf-level responses of different protective components to water deficit and high temperatures in Quercus cerris L. and Quercus robur L. Several biochemical components of the osmotic adjustment and antioxidant system were investigated together with changes in hormones. Q. cerris and Q. robur seedlings responded to water deficit and high temperatures by: (1) activating a different pattern of osmoregulation and antioxidant mechanisms depending on the species and on the nature of the stress; (2) upregulating the synthesis of a newly-explored osmoprotectant, dimethylsulphoniopropionate (DMSP); (3) trading-off between metabolites; and (4) modulating hormone levels. Under water deficit, Q. cerris had a higher antioxidant capacity compared to Q. robur, which showed a lower investment in the antioxidant system. In both species, exposure to high temperatures induced a strong osmoregulation capacity that appeared largely conferred by DMSP in Q. cerris and by glycine betaine in Q. robur. Collectively, the more stress-responsive compounds in each species were those present at a significant basal level in non-stress conditions. Our results were discussed in terms of pre-adaptation and stress-induced metabolic patterns as related to species-specific stress tolerance features.

Published
2022

35. Nutrients in Antarctic land-fast sea ice and exchange with the surface ocean

Author

the UK Challenger Society biennial meeting (2022-09-5), Henley, Sian S.F., Cozzi, Stefano, Fripiat, François, Meiners, Klaus Martin, Vancoppenolle, Martin, Lannuzel, Delphine, Thomas, David D.N., Nomura, Daïki, Arrigo, Kevin K.R., Delille, Bruno, Deman, Florian, Stefels, Jacqueline, Van Leeuwe, Maria M.A., Jones, Elisabeth, Fransson, Agneta A.F., Chierici, Melissa M.C., Moreau, Sébastien, the UK Challenger Society biennial meeting (2022-09-5), Henley, Sian S.F., Cozzi, Stefano, Fripiat, François, Meiners, Klaus Martin, Vancoppenolle, Martin, Lannuzel, Delphine, Thomas, David D.N., Nomura, Daïki, Arrigo, Kevin K.R., Delille, Bruno, Deman, Florian, Stefels, Jacqueline, Van Leeuwe, Maria M.A., Jones, Elisabeth, Fransson, Agneta A.F., Chierici, Melissa M.C., and Moreau, Sébastien

Abstract

info:eu-repo/semantics/nonPublished

Published
2022

40. Carbon and nutrient cycling in Antarctic landfast sea ice from winter to summer.

Author

Jones, Elizabeth M., Henley, Sian F., van Leeuwe, Maria A., Stefels, Jacqueline, Meredith, Michael P., Fenton, Mairi, and Venables, Hugh J.

Subjects
NUTRIENT cycles, CARBON cycle, SPRING, BIOGEOCHEMICAL cycles, ATMOSPHERIC carbon dioxide, SEA ice, SUMMER
Abstract

Seasonal cycling in carbon, alkalinity, and nutrients in landfast sea ice in Hangar Cove, Adelaide Island, West Antarctic Peninsula, were investigated during winter, spring, and summer 2014–2015. Temporal dynamics were driven by changes in the sea‐ice physicochemical conditions, ice‐algal community composition, and organic matter production. Winter sea ice was enriched with dissolved inorganic carbon (DIC) and inorganic nutrients from organic matter remineralization. Variations in alkalinity (Alk) and DIC indicated that abiotic calcium carbonate (ikaite) precipitation had taken place. Relative to other nutrients, low phosphate (PO4) concentrations potentially resulted from co‐precipitation with ikaite. Seawater flooding and meltwater induced variability in the physical and biogeochemical properties in the upper ice in spring where nutrient resupply supported haptophyte productivity and increased particulate organic carbon (POC) in the interstitial layer. Rapid nitrate (NO3) and DIC (< 165 μmol kg−1) uptake occurred alongside substantial build‐up of algal biomass (746 μg chlorophyll a L−1) and POC (6191 μmol L−1) during summer. Silicic acid drawdown followed NO3 depletion by approximately 1 month with a shift to diatom‐dominated communities. Accumulation of PO4 in the lower ice layers in summer likely resulted from PO4 released during ikaite dissolution in the presence of biofilms. Increased Alk : DIC ratios in the lower ice and under‐ice water suggested that ikaite dissolution buffered against meltwater dilution and enhanced the potential for atmospheric CO2 uptake. This study revealed strong seasonality in carbon and nutrient cycling in landfast sea ice and showed the importance of sea ice in biogeochemical cycling in seasonally ice‐covered waters around Antarctica. [ABSTRACT FROM AUTHOR]

Published
2023
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43. Evolution of physical properties of sea ice for multiple ice types at the MOSAiC central floe and the distributed network

Author

Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Nomura, Daiki, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, Zhan, Liyang, Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Nomura, Daiki, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, and Zhan, Liyang

Published
2021

44. Sea ice permeability evolution on Arctic first and second-year ice on the drifting MOSAiC floe from autumn to spring

Author

Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, Zhan, Liyang, Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, and Zhan, Liyang

Published
2021

45. Spatial variability and evolution of sea ice permeability on the MOSAiC central floe from autumn to spring: Biogeochemistry research sites

Author

Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Oggier, Marc, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, Zhan, Liyang, Haas, Christian, Angelopoulos, Michael, Damm, Ellen, Simoes Pereira, Patric, Abrahamsson, Katarina, Bauch, Dorothea, Bowman, Jeff, Dumitrascu, Adela, Krumpen, Thomas, Marsay, Chris, Oggier, Marc, Rinke, Annette, Stefels, Jacqueline, Sachs, Torsten, Stephens, Mark, Verdugo, Maria Josefa, Wang, Lei, Zhan, Liyang, and Haas, Christian

Published
2021

46. BEPSII Arctic Policy Brief

Author

Steiner, Nadja, Stefels, Jacqueline, Bowman, Jeff S., Castellani, Giulia, Crabeck, Odile, Delille, B., Else, Brent, Flores, Hauke, Fripiat, François, Lannuzel, Delphine, Meiners, K., Miller, L., Moreau, Sébastien, Nomura, Daïki, Tedesco, Letizia, Vancoppenolle, Martin, Steiner, Nadja, Stefels, Jacqueline, Bowman, Jeff S., Castellani, Giulia, Crabeck, Odile, Delille, B., Else, Brent, Flores, Hauke, Fripiat, François, Lannuzel, Delphine, Meiners, K., Miller, L., Moreau, Sébastien, Nomura, Daïki, Tedesco, Letizia, and Vancoppenolle, Martin

Abstract

info:eu-repo/semantics/published

Published
2021

47. Short-Lived Trace Gases in the Surface Ocean and the Atmosphere

Author

Liss, Peter S., primary, Marandino, Christa A., additional, Dahl, Elizabeth E., additional, Helmig, Detlev, additional, Hintsa, Eric J., additional, Hughes, Claire, additional, Johnson, Martin T., additional, Moore, Robert M., additional, Plane, John M. C., additional, Quack, Birgit, additional, Singh, Hanwant B., additional, Stefels, Jacqueline, additional, von Glasow, Roland, additional, and Williams, Jonathan, additional

Published
2013
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