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3. Overview of the MOSAiC expedition - Atmosphere

Author

Shupe, Matthew D., Rex, Markus, Blomquist, Byron, Persson, P. Ola G., Schmale, Julia, Uttal, Taneil, Althausen, Dietrich, Angot, Hélène, Archer, Stephen, Bariteau, Ludovic, Beck, Ivo, Bilberry, John, Bucci, Silvia, Buck, Clifton, Boyer, Matt, Brasseur, Zoé, Brooks, Ian M., Calmer, Radiance, Cassano, John, Castro, Vagner, Chu, David, Costa, David, Cox, Christopher J., Creamean, Jessie, Crewell, Susanne, Dahlke, Sandro, Damm, Ellen, de Boer, Gijs, Deckelmann, Holger, Dethloff, Klaus, Dütsch, Marina, Ebell, Kerstin, Ehrlich, André, Ellis, Jody, Engelmann, Ronny, Fong, Allison A., Frey, Markus M., Gallagher, Michael R., Ganzeveld, Laurens, Gradinger, Rolf, Graeser, Jürgen, Greenamyer, Vernon, Griesche, Hannes, Griffiths, Steele, Hamilton, Jonathan, Heinemann, Günther, Helmig, Detlev, Herber, Andreas, Heuzé, Céline, Hofer, Julian, Houchens, Todd, Howard, Dean, Inoue, Jun, Jacobi, Hans-Werner, Jaiser, Ralf, Jokinen, Tuija, Jourdan, Olivier, Jozef, Gina, King, Wessley, Kirchgaessner, Amelie, Klingebiel, Marcus, Krassovski, Misha, Krumpen, Thomas, Lampert, Astrid, Landing, William, Laurila, Tiia, Lawrence, Dale, Lonardi, Michael, Loose, Brice, Lüpkes, Christof, Maahn, Maximilian, Macke, Andreas, Maslowski, Wieslaw, Marsay, Christopher, Maturilli, Marion, Mech, Mario, Morris, Sara, Moser, Manuel, Nicolaus, Marcel, Ortega, Paul, Osborn, Jackson, Pätzold, Falk, Perovich, Donald K., Petäjä, Tuukka, Pilz, Christian, Pirazzini, Roberta, Posman, Kevin, Powers, Heath, Pratt, Kerri A., Preußer, Andreas, Quéléver, Lauriane, Radenz, Martin, Rabe, Benjamin, Rinke, Annette, Sachs, Torsten, Schulz, Alexander, Siebert, Holger, Silva, Tercio, Solomon, Amy, Sommerfeld, Anja, Spreen, Gunnar, Stephens, Mark, Stohl, Andreas, Svensson, Gunilla, Uin, Janek, Viegas, Juarez, Voigt, Christiane, von der Gathen, Peter, Wehner, Birgit, Welker, Jeffrey M., Wendisch, Manfred, Werner, Martin, Xie, ZhouQing, Yue, Fange, Shupe, Matthew D., Rex, Markus, Blomquist, Byron, Persson, P. Ola G., Schmale, Julia, Uttal, Taneil, Althausen, Dietrich, Angot, Hélène, Archer, Stephen, Bariteau, Ludovic, Beck, Ivo, Bilberry, John, Bucci, Silvia, Buck, Clifton, Boyer, Matt, Brasseur, Zoé, Brooks, Ian M., Calmer, Radiance, Cassano, John, Castro, Vagner, Chu, David, Costa, David, Cox, Christopher J., Creamean, Jessie, Crewell, Susanne, Dahlke, Sandro, Damm, Ellen, de Boer, Gijs, Deckelmann, Holger, Dethloff, Klaus, Dütsch, Marina, Ebell, Kerstin, Ehrlich, André, Ellis, Jody, Engelmann, Ronny, Fong, Allison A., Frey, Markus M., Gallagher, Michael R., Ganzeveld, Laurens, Gradinger, Rolf, Graeser, Jürgen, Greenamyer, Vernon, Griesche, Hannes, Griffiths, Steele, Hamilton, Jonathan, Heinemann, Günther, Helmig, Detlev, Herber, Andreas, Heuzé, Céline, Hofer, Julian, Houchens, Todd, Howard, Dean, Inoue, Jun, Jacobi, Hans-Werner, Jaiser, Ralf, Jokinen, Tuija, Jourdan, Olivier, Jozef, Gina, King, Wessley, Kirchgaessner, Amelie, Klingebiel, Marcus, Krassovski, Misha, Krumpen, Thomas, Lampert, Astrid, Landing, William, Laurila, Tiia, Lawrence, Dale, Lonardi, Michael, Loose, Brice, Lüpkes, Christof, Maahn, Maximilian, Macke, Andreas, Maslowski, Wieslaw, Marsay, Christopher, Maturilli, Marion, Mech, Mario, Morris, Sara, Moser, Manuel, Nicolaus, Marcel, Ortega, Paul, Osborn, Jackson, Pätzold, Falk, Perovich, Donald K., Petäjä, Tuukka, Pilz, Christian, Pirazzini, Roberta, Posman, Kevin, Powers, Heath, Pratt, Kerri A., Preußer, Andreas, Quéléver, Lauriane, Radenz, Martin, Rabe, Benjamin, Rinke, Annette, Sachs, Torsten, Schulz, Alexander, Siebert, Holger, Silva, Tercio, Solomon, Amy, Sommerfeld, Anja, Spreen, Gunnar, Stephens, Mark, Stohl, Andreas, Svensson, Gunilla, Uin, Janek, Viegas, Juarez, Voigt, Christiane, von der Gathen, Peter, Wehner, Birgit, Welker, Jeffrey M., Wendisch, Manfred, Werner, Martin, Xie, ZhouQing, and Yue, Fange

Abstract

With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore cross-cutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system

Published
2022

4. Overview of the MOSAiC expedition: Physical oceanography

Author

Rabe, Benjamin, Heuzé, Céline, Regnery, Julia, Aksenov, Yevgeny, Allerholt, Jacob, Athanase, Marylou, Bai, Youcheng, Basque, Chris, Bauch, Dorothea, Baumann, Till M., Chen, Dake, Cole, Sylvia T., Craw, Lisa, Davies, Andrew, Damm, Ellen, Dethloff, Klaus, Divine, Dmitry V., Doglioni, Francesca, Ebert, Falk, Fang, Ying-Chih, Fer, Ilker, Fong, Allison A., Gradinger, Rolf, Granskog, Mats A., Graupner, Rainer, Haas, Christian, He, Hailun, He, Yan, Hoppmann, Mario, Janout, Markus, Kadko, David, Kanzow, Torsten, Karam, Salar, Kawaguchi, Yusuke, Koenig, Zoe, Kong, Bin, Krishfield, Richard A., Krumpen, Thomas, Kuhlmey, David, Kuznetsov, Ivan, Lan, Musheng, Laukert, Georgi, Lei, Ruibo, Li, Tao, Torres-Valdés, Sinhué, Lin, Lina, Lin, Long, Liu, Hailong, Liu, Na, Loose, Brice, Ma, Xiaobing, McKay, Rosalie, Mallet, Maria, Mallett, Robbie D. C., Maslowski, Wieslaw, Mertens, Christian, Mohrholz, Volker, Muilwijk, Morven, Nicolaus, Marcel, O’Brien, Jeffrey K., Perovich, Donald, Ren, Jian, Rex, Markus, Ribeiro, Natalia, Rinke, Annette, Schaffer, Janin, Schuffenhauer, Ingo, Schulz, Kirstin, Shupe, Matthew D., Shaw, William, Sokolov, Vladimir, Sommerfeld, Anja, Spreen, Gunnar, Stanton, Timothy, Stephens, Mark, Su, Jie, Sukhikh, Natalia, Sundfjord, Arild, Thomisch, Karolin, Tippenhauer, Sandra, Toole, John M., Vredenborg, Myriel, Walter, Maren, Wang, Hangzhou, Wang, Lei, Wang, Yuntao, Wendisch, Manfred, Zhao, Jinping, Zhou, Meng, Zhu, Jialiang, Rabe, Benjamin, Heuzé, Céline, Regnery, Julia, Aksenov, Yevgeny, Allerholt, Jacob, Athanase, Marylou, Bai, Youcheng, Basque, Chris, Bauch, Dorothea, Baumann, Till M., Chen, Dake, Cole, Sylvia T., Craw, Lisa, Davies, Andrew, Damm, Ellen, Dethloff, Klaus, Divine, Dmitry V., Doglioni, Francesca, Ebert, Falk, Fang, Ying-Chih, Fer, Ilker, Fong, Allison A., Gradinger, Rolf, Granskog, Mats A., Graupner, Rainer, Haas, Christian, He, Hailun, He, Yan, Hoppmann, Mario, Janout, Markus, Kadko, David, Kanzow, Torsten, Karam, Salar, Kawaguchi, Yusuke, Koenig, Zoe, Kong, Bin, Krishfield, Richard A., Krumpen, Thomas, Kuhlmey, David, Kuznetsov, Ivan, Lan, Musheng, Laukert, Georgi, Lei, Ruibo, Li, Tao, Torres-Valdés, Sinhué, Lin, Lina, Lin, Long, Liu, Hailong, Liu, Na, Loose, Brice, Ma, Xiaobing, McKay, Rosalie, Mallet, Maria, Mallett, Robbie D. C., Maslowski, Wieslaw, Mertens, Christian, Mohrholz, Volker, Muilwijk, Morven, Nicolaus, Marcel, O’Brien, Jeffrey K., Perovich, Donald, Ren, Jian, Rex, Markus, Ribeiro, Natalia, Rinke, Annette, Schaffer, Janin, Schuffenhauer, Ingo, Schulz, Kirstin, Shupe, Matthew D., Shaw, William, Sokolov, Vladimir, Sommerfeld, Anja, Spreen, Gunnar, Stanton, Timothy, Stephens, Mark, Su, Jie, Sukhikh, Natalia, Sundfjord, Arild, Thomisch, Karolin, Tippenhauer, Sandra, Toole, John M., Vredenborg, Myriel, Walter, Maren, Wang, Hangzhou, Wang, Lei, Wang, Yuntao, Wendisch, Manfred, Zhao, Jinping, Zhou, Meng, and Zhu, Jialiang

Abstract

Arctic Ocean properties and processes are highly relevant to the regional and global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography observations as part of the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC), a drift with the Arctic sea ice from October 2019 to September 2020. An international team designed and implemented the program to characterize the Arctic Ocean system in unprecedented detail, from the seafloor to the air-sea ice-ocean interface, from sub-mesoscales to pan-Arctic. The oceanographic measurements were coordinated with the other teams to explore the ocean physics and linkages to the climate and ecosystem. This paper introduces the major components of the physical oceanography program and complements the other team overviews of the MOSAiC observational program. Team OCEAN’s sampling strategy was designed around hydrographic ship-, ice- and autonomous platform-based measurements to improve the understanding of regional circulation and mixing processes. Measurements were carried out both routinely, with a regular schedule, and in response to storms or opening leads. Here we present alongdrift time series of hydrographic properties, allowing insights into the seasonal and regional evolution of the water column from winter in the Laptev Sea to early summer in Fram Strait: freshening of the surface, deepening of the mixed layer, increase in temperature and salinity of the Atlantic Water. We also highlight the presence of Canada Basin deep water intrusions and a surface meltwater layer in leads. MOSAiC most likely was the most comprehensive program ever conducted over the ice-covered Arctic Ocean. While data analysis and interpretation are ongoing, the acquired datasets will support a wide range of physical oceanography and multi-disciplinary research. They will provide a significant foundation for assessing and advancing modeling cap

Published
2022

5. Arctic sea ice anomalies during the MOSAiC winter 2019/20

Author

Dethloff, Klaus, Maslowski, Wieslaw, Hendricks, Stefan, Lee, Younjoo J., Goessling, Helge F., Krumpen, Thomas, Haas, Christian, Handorf, Dörthe, Ricker, Robert, Bessonov, Vladimir, Cassano, John J., Kinney, Jaclyn Clement, Osinski, Robert, Rex, Markus, Rinke, Annette, Sokolova, Julia, Sommerfeld, Anja, Dethloff, Klaus, Maslowski, Wieslaw, Hendricks, Stefan, Lee, Younjoo J., Goessling, Helge F., Krumpen, Thomas, Haas, Christian, Handorf, Dörthe, Ricker, Robert, Bessonov, Vladimir, Cassano, John J., Kinney, Jaclyn Clement, Osinski, Robert, Rex, Markus, Rinke, Annette, Sokolova, Julia, and Sommerfeld, Anja

Published
2022

6. Overview of the MOSAiC expedition-Atmosphere INTRODUCTION

Author

Shupe, Matthew D., Rex, Markus, Blomquist, Byron, Persson, P. Ola G., Schmale, Julia, Uttal, Taneil, Althausen, Dietrich, Angot, Helene, Archer, Stephen, Bariteau, Ludovic, Beck, Ivo, Bilberry, John, Bucci, Silvia, Buck, Clifton, Boyer, Matt, Brasseur, Zoe, Brooks, Ian M., Calmer, Radiance, Cassano, John, Castro, Vagner, Chu, David, Costa, David, Cox, Christopher J., Creamean, Jessie, Crewell, Susanne, Dahlke, Sandro, Damm, Ellen, de Boer, Gijs, Deckelmann, Holger, Dethloff, Klaus, Duetsch, Marina, Ebell, Kerstin, Ehrlich, Andre, Ellis, Jody, Engelmann, Ronny, Fong, Allison A., Frey, Markus M., Gallagher, Michael R., Ganzeveld, Laurens, Gradinger, Rolf, Graeser, Juergen, Greenamyer, Vernon, Griesche, Hannes, Griffiths, Steele, Hamilton, Jonathan, Heinemann, Guenther, Helmig, Detlev, Herber, Andreas, Heuze, Celine, Hofer, Julian, Houchens, Todd, Howard, Dean, Inoue, Jun, Jacobi, Hans-Werner, Jaiser, Ralf, Jokinen, Tuija, Jourdan, Olivier, Jozef, Gina, King, Wessley, Kirchgaessner, Amelie, Klingebiel, Marcus, Krassovski, Misha, Krumpen, Thomas, Lampert, Astrid, Landing, William, Laurila, Tiia, Lawrence, Dale, Lonardi, Michael, Loose, Brice, Luepkes, Christof, Maahn, Maximilian, Macke, Andreas, Maslowski, Wieslaw, Marsay, Christopher, Maturilli, Marion, Mech, Mario, Morris, Sara, Moser, Manuel, Nicolaus, Marcel, Ortega, Paul, Osborn, Jackson, Paetzold, Falk, Perovich, Donald K., Petaja, Tuukka, Pilz, Christian, Pirazzini, Roberta, Posman, Kevin, Powers, Heath, Pratt, Kerri A., Preusser, Andreas, Quelever, Lauriane, Radenz, Martin, Rabe, Benjamin, Rinke, Annette, Sachs, Torsten, Schulz, Alexander, Siebert, Holger, Silva, Tercio, Solomon, Amy, Sommerfeld, Anja, Spreen, Gunnar, Stephens, Mark, Stohl, Andreas, Svensson, Gunilla, Uin, Janek, Viegas, Juarez, Voigt, Christiane, von der Gathen, Peter, Wehner, Birgit, Welker, Jeffrey M., Wendisch, Manfred, Werner, Martin, Xie, ZhouQing, Yue, Fange, Shupe, Matthew D., Rex, Markus, Blomquist, Byron, Persson, P. Ola G., Schmale, Julia, Uttal, Taneil, Althausen, Dietrich, Angot, Helene, Archer, Stephen, Bariteau, Ludovic, Beck, Ivo, Bilberry, John, Bucci, Silvia, Buck, Clifton, Boyer, Matt, Brasseur, Zoe, Brooks, Ian M., Calmer, Radiance, Cassano, John, Castro, Vagner, Chu, David, Costa, David, Cox, Christopher J., Creamean, Jessie, Crewell, Susanne, Dahlke, Sandro, Damm, Ellen, de Boer, Gijs, Deckelmann, Holger, Dethloff, Klaus, Duetsch, Marina, Ebell, Kerstin, Ehrlich, Andre, Ellis, Jody, Engelmann, Ronny, Fong, Allison A., Frey, Markus M., Gallagher, Michael R., Ganzeveld, Laurens, Gradinger, Rolf, Graeser, Juergen, Greenamyer, Vernon, Griesche, Hannes, Griffiths, Steele, Hamilton, Jonathan, Heinemann, Guenther, Helmig, Detlev, Herber, Andreas, Heuze, Celine, Hofer, Julian, Houchens, Todd, Howard, Dean, Inoue, Jun, Jacobi, Hans-Werner, Jaiser, Ralf, Jokinen, Tuija, Jourdan, Olivier, Jozef, Gina, King, Wessley, Kirchgaessner, Amelie, Klingebiel, Marcus, Krassovski, Misha, Krumpen, Thomas, Lampert, Astrid, Landing, William, Laurila, Tiia, Lawrence, Dale, Lonardi, Michael, Loose, Brice, Luepkes, Christof, Maahn, Maximilian, Macke, Andreas, Maslowski, Wieslaw, Marsay, Christopher, Maturilli, Marion, Mech, Mario, Morris, Sara, Moser, Manuel, Nicolaus, Marcel, Ortega, Paul, Osborn, Jackson, Paetzold, Falk, Perovich, Donald K., Petaja, Tuukka, Pilz, Christian, Pirazzini, Roberta, Posman, Kevin, Powers, Heath, Pratt, Kerri A., Preusser, Andreas, Quelever, Lauriane, Radenz, Martin, Rabe, Benjamin, Rinke, Annette, Sachs, Torsten, Schulz, Alexander, Siebert, Holger, Silva, Tercio, Solomon, Amy, Sommerfeld, Anja, Spreen, Gunnar, Stephens, Mark, Stohl, Andreas, Svensson, Gunilla, Uin, Janek, Viegas, Juarez, Voigt, Christiane, von der Gathen, Peter, Wehner, Birgit, Welker, Jeffrey M., Wendisch, Manfred, Werner, Martin, Xie, ZhouQing, and Yue, Fange

Abstract

With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore crosscutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system s

Published
2022

7. Arctic sea ice anomalies during the MOSAiC winter 2019/20

Author

Dethloff, Klaus, primary, Maslowski, Wieslaw, additional, Hendricks, Stefan, additional, Lee, Younjoo J., additional, Goessling, Helge F., additional, Krumpen, Thomas, additional, Haas, Christian, additional, Handorf, Dörthe, additional, Ricker, Robert, additional, Bessonov, Vladimir, additional, Cassano, John J., additional, Kinney, Jaclyn Clement, additional, Osinski, Robert, additional, Rex, Markus, additional, Rinke, Annette, additional, Sokolova, Julia, additional, and Sommerfeld, Anja, additional

Published
2022
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8. Overview of the MOSAiC expedition: Atmosphere

Author

Shupe, Matthew, Rex, Markus, Blomquist, Byron, Ola, P, Persson, G, Schmale, Julia, Uttal, Taneil, Althausen, Dietrich, Lè Ne Angot, Hé, Archer, Stephen, Bariteau, Ludovic, Beck, Ivo, Bilberry, John, Bucci, Silvia, Buck, Clifton, Boyer, Matt, Brasseur, Zoé, Brooks, Ian, Cassano, John, Castro, Vagner, Chu, David, Costa, David, Cox, Christopher, Creamean, Jessie, Crewell, Susanne, Dahlke, Sandro, Damm, Ellen, de Boer, Gijs, Deckelmann, Holger, Dethloff, Klaus, Dütsch, Marina, Ebell, Kerstin, Ehrlich, André, Ellis, Jody, Engelmann, Ronny, Fong, Allison, Frey, Markus, Gallagher, Michael, Ganzeveld, Laurens, Gradinger, Rolf, Graeser, Jürgen, Greenamyer, Vernon, Griesche, Hannes, Griffiths, Steele, Hamilton, Jonathan, Heinemann, Günther, Helmig, Detlev, Herber, Andreas, Line Heuzé, Cé, Hofer, Julian, Houchens, Todd, Inoue, Jun, Jacobi, Hans-Werner, Jaiser, Ralf, Jokinen, Tuija, Jourdan, Olivier, King, Wessley, Kirchgaessner, Amelie, Klingebiel, Marcus, Krassovski, Misha, Krumpen, Thomas, Lampert, Astrid, Landing, William, Laurila, Tiia, Lawrence, Dale, Lonardi, Michael, Loose, Brice, Lüpkes, Christof, Maahn, Maximilian, Macke, Andreas, Maslowski, Wieslaw, Marsay, Christopher, Maturilli, Marion, Mech, Mario, Morris, Sara, Moser, Manuel, Nicolaus, Marcel, Ortega, Paul, Osborn, Jackson, Pätzold, Falk, Perovich, Donald, Petäjä, Tuukka, Pilz, Christian, Pirazzini, Roberta, Posman, Kevin, Powers, Heath, Pratt, Kerri, Preusser, Andreas, Qué Lé Ver, Lauriane, Radenz, Martin, Rabe, Benjamin, Rinke, Annette, Sachs, Torsten, Schulz, Alexander, Siebert, Holger, Silva, Tercio, Solomon, Amy, Sommerfeld, Anja, Spreen, Gunnar, Stephens, Mark, Stohl, Andreas, Svensson, Gunilla, Uin, Janek, Viegas, Juarez, Voigt, Christiane, von Der Gathen, Peter, Wehner, Birgit, Welker, Jeffrey, Wendisch, Manfred, Werner, Martin, Xie, Zhouqing, Yue, Fange, Jourdan, Olivier, 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
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Arctic, Field campaign, Atmosphere, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere
Abstract

International audience; With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore crosscutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge.The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system scientific research and provide an important foundation for advancing multiscale modeling capabilities in the Arctic.

Published
2022

9. Overview of the MOSAiC expedition: Physical oceanography

Author

Rabe, Benjamin, primary, Heuzé, Céline, additional, Regnery, Julia, additional, Aksenov, Yevgeny, additional, Allerholt, Jacob, additional, Athanase, Marylou, additional, Bai, Youcheng, additional, Basque, Chris, additional, Bauch, Dorothea, additional, Baumann, Till M., additional, Chen, Dake, additional, Cole, Sylvia T., additional, Craw, Lisa, additional, Davies, Andrew, additional, Damm, Ellen, additional, Dethloff, Klaus, additional, Divine, Dmitry V., additional, Doglioni, Francesca, additional, Ebert, Falk, additional, Fang, Ying-Chih, additional, Fer, Ilker, additional, Fong, Allison A., additional, Gradinger, Rolf, additional, Granskog, Mats A., additional, Graupner, Rainer, additional, Haas, Christian, additional, He, Hailun, additional, He, Yan, additional, Hoppmann, Mario, additional, Janout, Markus, additional, Kadko, David, additional, Kanzow, Torsten, additional, Karam, Salar, additional, Kawaguchi, Yusuke, additional, Koenig, Zoe, additional, Kong, Bin, additional, Krishfield, Richard A., additional, Krumpen, Thomas, additional, Kuhlmey, David, additional, Kuznetsov, Ivan, additional, Lan, Musheng, additional, Laukert, Georgi, additional, Lei, Ruibo, additional, Li, Tao, additional, Torres-Valdés, Sinhué, additional, Lin, Lina, additional, Lin, Long, additional, Liu, Hailong, additional, Liu, Na, additional, Loose, Brice, additional, Ma, Xiaobing, additional, McKay, Rosalie, additional, Mallet, Maria, additional, Mallett, Robbie D. C., additional, Maslowski, Wieslaw, additional, Mertens, Christian, additional, Mohrholz, Volker, additional, Muilwijk, Morven, additional, Nicolaus, Marcel, additional, O’Brien, Jeffrey K., additional, Perovich, Donald, additional, Ren, Jian, additional, Rex, Markus, additional, Ribeiro, Natalia, additional, Rinke, Annette, additional, Schaffer, Janin, additional, Schuffenhauer, Ingo, additional, Schulz, Kirstin, additional, Shupe, Matthew D., additional, Shaw, William, additional, Sokolov, Vladimir, additional, Sommerfeld, Anja, additional, Spreen, Gunnar, additional, Stanton, Timothy, additional, Stephens, Mark, additional, Su, Jie, additional, Sukhikh, Natalia, additional, Sundfjord, Arild, additional, Thomisch, Karolin, additional, Tippenhauer, Sandra, additional, Toole, John M., additional, Vredenborg, Myriel, additional, Walter, Maren, additional, Wang, Hangzhou, additional, Wang, Lei, additional, Wang, Yuntao, additional, Wendisch, Manfred, additional, Zhao, Jinping, additional, Zhou, Meng, additional, and Zhu, Jialiang, additional

Published
2022
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10. MOSAiC Extended Acknowledgement

Author

Nixdorf, Uwe, Dethloff, Klaus, Rex, Markus, Shupe, Matthew, Sommerfeld, Anja, Perovich, Donald K., Nicolaus, Marcel, Heuzé, Céline, Rabe, Benjamin, Loose, Brice, Damm, Ellen, Gradinger, Rolf, Fong, Allison, Maslowski, Wieslaw, Rinke, Annette, Kwok, Ronald, Spreen, Gunnar, Wendisch, Manfred, Herber, Andreas, Hirsekorn, Marius, Mohaupt, Verena, Frickenhaus, Stephan, Immerz, Antonia, Weiss-Tuider, Katharina, König, Bjela, Mengedoht, Dirk, Regnery, Julia, Gerchow, Peter, Ransby, Daniela, Krumpen, Thomas, Morgenstern, Anne, Haas, Christian, Kanzow, Torsten, Rack, Frank R., Saitzev, Vladimir, Sokolov, Vladimir, Makarov, Alexander, Schwarze, Stefan, Wunderlich, Thomas, Wurr, Karsten, Boetius, Antje, Nixdorf, Uwe, Dethloff, Klaus, Rex, Markus, Shupe, Matthew, Sommerfeld, Anja, Perovich, Donald K., Nicolaus, Marcel, Heuzé, Céline, Rabe, Benjamin, Loose, Brice, Damm, Ellen, Gradinger, Rolf, Fong, Allison, Maslowski, Wieslaw, Rinke, Annette, Kwok, Ronald, Spreen, Gunnar, Wendisch, Manfred, Herber, Andreas, Hirsekorn, Marius, Mohaupt, Verena, Frickenhaus, Stephan, Immerz, Antonia, Weiss-Tuider, Katharina, König, Bjela, Mengedoht, Dirk, Regnery, Julia, Gerchow, Peter, Ransby, Daniela, Krumpen, Thomas, Morgenstern, Anne, Haas, Christian, Kanzow, Torsten, Rack, Frank R., Saitzev, Vladimir, Sokolov, Vladimir, Makarov, Alexander, Schwarze, Stefan, Wunderlich, Thomas, Wurr, Karsten, and Boetius, Antje

Abstract

For years, the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), together with the international MOSAiC partners, had been planning and developing the scientific, logistical and financial concept for the implementation of the MOSAiC expedition. The planning and organization of this endeavor was an enormous e˙ort, involving more than 80 institutions from 20 countries. The number of groups and individuals that significantly contributed to the success of the drift observatory goes far beyond the scope of usual polar expeditions.

Published
2021

11. Arctic sea ice anomalies during the MOSAiC winter 2019/20

Author

Dethloff, Klaus, primary, Maslowski, Wieslaw, additional, Hendricks, Stefan, additional, Lee, Younjoo, additional, Goessling, Helge F., additional, Krumpen, Thomas, additional, Haas, Christian, additional, Handorf, Dörthe, additional, Ricker, Robert, additional, Bessonov, Vladimir, additional, Cassano, John J., additional, Kinney, Jaclyn Clement, additional, Osinski, Robert, additional, Rex, Markus, additional, Rinke, Annette, additional, Sokolova, Julia, additional, and Sommerfeld, Anja, additional

Published
2021
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12. Supplementary material to "Arctic sea ice anomalies during the MOSAiC winter 2019/20"

Author

Dethloff, Klaus, primary, Maslowski, Wieslaw, additional, Hendricks, Stefan, additional, Lee, Younjoo, additional, Goessling, Helge F., additional, Krumpen, Thomas, additional, Haas, Christian, additional, Handorf, Dörthe, additional, Ricker, Robert, additional, Bessonov, Vladimir, additional, Cassano, John J., additional, Kinney, Jaclyn Clement, additional, Osinski, Robert, additional, Rex, Markus, additional, Rinke, Annette, additional, Sokolova, Julia, additional, and Sommerfeld, Anja, additional

Published
2021
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13. MOSAiC School.

Author

Lenz, Josefine, Rackow, Thomas, Fugmann, Gerlis, Sommerfeld, Anja, Schneider, Andrea, and Grosfeld, Lisa

Published
2020

14. Quantifizierung der modellinternen Variabilität der Arktischen Sommeratmosphäre basierend auf HIRHAM5 Ensemblesimulationen

Author

Sommerfeld, Anja

Subjects
pacs:92.60.Uy, Institut für Physik und Astronomie, ddc:530, pacs:92.60.Aa
Abstract

The non-linear behaviour of the atmospheric dynamics is not well understood and makes the evaluation and usage of regional climate models (RCMs) difficult. Due to these non-linearities, chaos and internal variability (IV) within the RCMs are induced, leading to a sensitivity of RCMs to their initial conditions (IC). The IV is the ability of RCMs to realise different solutions of simulations that differ in their IC, but have the same lower and lateral boundary conditions (LBC), hence can be defined as the across-member spread between the ensemble members. For the investigation of the IV and the dynamical and diabatic contributions generating the IV four ensembles of RCM simulations are performed with the atmospheric regional model HIRHAM5. The integration area is the Arctic and each ensemble consists of 20 members. The ensembles cover the time period from July to September for the years 2006, 2007, 2009 and 2012. The ensemble members have the same LBC and differ in their IC only. The different IC are arranged by an initialisation time that shifts successively by six hours. Within each ensemble the first simulation starts on 1st July at 00 UTC and the last simulation starts on 5th July at 18 UTC and each simulation runs until 30th September. The analysed time period ranges from 6th July to 30th September, the time period that is covered by all ensemble members. The model runs without any nudging to allow a free development of each simulation to get the full internal variability within the HIRHAM5. As a measure of the model generated IV, the across-member standard deviation and the across-member variance is used and the dynamical and diabatic processes influencing the IV are estimated by applying a diagnostic budget study for the IV tendency of the potential temperature developed by Nikiema and Laprise [2010] and Nikiema and Laprise [2011]. The diagnostic budget study is based on the first law of thermodynamics for potential temperature and the mass-continuity equation. The resulting budget equation reveals seven contributions to the potential temperature IV tendency. As a first study, this work analyses the IV within the HIRHAM5. Therefore, atmospheric circulation parameters and the potential temperature for all four ensemble years are investigated. Similar to previous studies, the IV fluctuates strongly in time. Further, due to the fact that all ensemble members are forced with the same LBC, the IV depends on the vertical level within the troposphere, with high values in the lower troposphere and at 500 hPa and low values in the upper troposphere and at the surface. By the same reason, the spatial distribution shows low values of IV at the boundaries of the model domain. The diagnostic budget study for the IV tendency of potential temperature reveals that the seven contributions fluctuate in time like the IV. However, the individual terms reach different absolute magnitudes. The budget study identifies the horizontal and vertical ‘baroclinic’ terms as the main contributors to the IV tendency, with the horizontal ‘baroclinic’ term producing and the vertical ‘baroclinic’ term reducing the IV. The other terms fluctuate around zero, because they are small in general or are balanced due to the domain average. The comparison of the results obtained for the four different ensembles (summers 2006, 2007, 2009 and 2012) reveals that on average the findings for each ensemble are quite similar concerning the magnitude and the general pattern of IV and its contributions. However, near the surface a weaker IV is produced with decreasing sea ice extent. This is caused by a smaller impact of the horizontal 'baroclinic' term over some regions and by the changing diabatic processes, particularly a more intense reducing tendency of the IV due to condensative heating. However, it has to be emphasised that the behaviour of the IV and its dynamical and diabatic contributions are influenced mainly by complex atmospheric feedbacks and large-scale processes and not by the sea ice distribution. Additionally, a comparison with a second RCM covering the Arctic and using the same LBCs and IC is performed. For both models very similar results concerning the IV and its dynamical and diabatic contributions are found. Hence, this investigation leads to the conclusion that the IV is a natural phenomenon and is independent from the applied RCM. Das nicht-lineare Verhalten der atmosphärischen Dynamik ist noch immer nicht ausreichend verstanden und daher sind die Evaluierung und die Anwendung von regionalen Klimamodellen (RCM) schwierig. Aufgrund dieser Nicht-Linearitäten wird Chaos und modellinterne Variabilität (IV) in RCMs erzeugt, was zur Sensitivität der RCMs bezüglich ihrer Anfangsbedingungen führt. Die IV ist die Fähigkeit von RCMs, verschiedene Lösungen für Simulationen zu erzeugen, die sich in ihren Anfangsbedingungen unterschieden, aber die gleichen unteren und seitlichen Randbedingungen aufweisen. Daher kann die IV als die Spannweite zwischen den Ensemblemitgliedern definiert werden. Für die Untersuchung der IV und deren dynamische und diabatische Beiträge werden vier Ensembles mit dem atmosphärischen Regionalmodell HIRHAM5 erzeugt. Das Integrationsgebiet ist die Arktis und jedes Ensemble besteht aus 20 Ensemblemitgliedern. Die Ensembles umfassen den Zeitraum von Juli bis September für die Jahre 2006, 2007, 2009 und 2012. Die Mitglieder eines Ensembles haben alle die gleichen unteren und seitlichen Randbedingungen und unterscheiden sich nur in ihren Anfangsbedingungen. Die unterschiedlichen Anfangsbedingungen werden durch eine Verschiebung der Initialisierungszeit um jeweils 6 Stunden erzeugt. Innerhalb eines jeden Ensembles wird die erste Simulation am 1. Juli um 00 UTC gestartet und die letzte Simulation beginnt am 5. Juli um 18 UTC. Jede Simulation endet am 30. September. Um gleich lange Simulationen für die Auswertung zu gewährleisten, wird die Studie für den Zeitraum vom 6. Juli bis 30. September durchgeführt. Das Modell wird ohne Nudging betrieben, um jeder Simulation eine freie Entwicklung zu gewähren und damit die modellinterne Variabilität des HIRHAM5 vollständig zu erhalten. Als Maβ für die im Modell generierte IV wird die Standardabweichung und die Varianz zwischen den Ensemblemitgliedern bestimmt. Die die IV beeinflussenden dynamischen und diabatischen Prozesse werden mit Hilfe der diagnostischen Budgetstudie zur Berechnung der IV Tendenz der potentiellen Temperatur bestimmt. Diese diagnostische Budgetstudie wurde von Nikiema and Laprise [2010] und Nikiema and Laprise [2011] entwickelt und basiert auf dem ersten Hauptsatz der Thermodynamik für die potentielle Temperatur und der Massenkontinuitätsgleichung. Aus der resultierenden Budgetgleichung können sieben Terme, die zu der Tendenz der potentiellen Temperatur beitragen, berechnet werden. In dieser Arbeit wird erstmalig die IV des HIRHAM5 analysiert. Dafür werden Parameter der atmosphärischen Zirkulation und die potentiellen Temperatur für alle vier Ensemblejahre analysiert. Wie auch frühere Studien zeigten, schwankt die IV stark mit der Zeit. Auβerdem wird eine vertikale Abhängigkeit der IV innerhalb der Troposphäre gefunden, mit hohen Werten in der unteren Troposphäre und in 500 hPa. Geringe Werte hingegen treten in der oberen Troposphäre und am Erdboden auf, da alle Ensemblemitglieder mit den gleichen Randbedingungen angetrieben werden. Daher zeigt auch die räumliche Verteilung niedrige IV Werte am Rand des Modellgebietes. Die diagnostische Budgetstudie für die IV Tendenz der potentiellen Temperatur verdeutlicht, dass die sieben Beiträge ebenfalls mit der Zeit schwanken wie die IV selbst. Jedoch erreichen die einzelnen Terme unterschiedliche Intensitäten. Mit Hilfe der Budgetstudie können der horizontale und vertikale 'Baroklinitätsterm' als die wichtigsten Beiträge zur Tendenz der IV ermittelt werden. Dabei trägt der horizontale 'Baroklinitätsterm' zur Produktion und der vertikale 'Baroklinitätsterm' zur Reduktion der IV bei. Die anderen Beiträge schwanken um Null, weil sie an sich klein oder aufgrund des Gebietsmittels ausbalanciert sind. Der Vergleich der Resultate für die Ensembles untereinander (Sommer 2006, 2007, 2009 und 2012) führt zu der Erkenntnis, das im Mittel die Ergebnisse für die IV und ihre Beiträge, die Gröβenordnung und die Muster betreffend, sehr ähnlich sind. Nur nahe der Erdoberfläche wird mit abnehmender Meereisausdehnung eine schwächere IV generiert. Dies ist bedingt durch einen geringeren Einfluss des horizontale 'Baroklinitätsterms' der in manchen Region auftritt sowie durch die sich ändernden diabatischen Prozesse (Tendenz zur intensiveren Reduktion der IV) aufgrund von Erwärmung durch Kondensation. Jedoch ist das Verhalten der IV und ihrer dynamischen und diabatischen Beiträge durch komplexe atmosphärische Rückkopplungen und groβskaligen Prozessen beeinflusst und nicht nur durch die Meereisverteilung. Des Weiteren wird ein Vergleich mit einem zweiten RCM durchgeführt. Dieses zweite RCM wird mit den selben unteren und seitlichen Randbedingungen und Anfangsbedingungen angetrieben wie das HIRHAM5. Für beide Modelle werden sehr ähnliche Ergebnisse für die IV und ihre dynamischen und diabatischen Beiträge gefunden. Daher führt die Untersuchung zu dem Schluss, dass die IV ein natürlichen Phänomen und damit unabhängig von dem verwendeten RCM ist.

Published
2015

17. Arctic budget study of intermember variability using HIRHAM5 ensemble simulations

Author

Sommerfeld, Anja, Nikiema, Oumarou, Rinke, Annette, Dethloff, Klaus, Laprise, René, Sommerfeld, Anja, Nikiema, Oumarou, Rinke, Annette, Dethloff, Klaus, and Laprise, René

Abstract

One of the challenges in evaluating and applying regional climate models (RCMs) is the nonlinear behavior of atmospheric processes, which is still poorly understood. The nonlinearities induce chaos which leads to an internal variability in the model. Therefore, an ensemble of RCM simulations has been run and a budget study for potential temperature has been applied to investigate the internally generated variability. Hence, the physical processes associated with diabatic and dynamical terms inducing the intermember variability have been analyzed. The study is applied over the Arctic on an ensemble of 20 members, differing in their initial conditions, simulated with the RCM HIRHAM5 during summer 2012. This time period is of particular importance because of the melting sea ice and its influence on atmospheric circulation and the resulting effect on the intermember variability. The amplitude of the intermember variability of the simulations fluctuates strongly both temporally and spatially. During the beginning of August 2012 the intermember variability is strongest and coincides with the great Arctic cyclone event. The most important contributions for the intermember variability tendency are the horizontal and vertical “baroclinic” terms. Both terms have largest absolute values along the coastlines of the Arctic Ocean which are associated with the Arctic frontal zone leading to the cyclone maximum over the Arctic Ocean during summer.

Published
2015

18. Quantification of Internal Variability of the Arctic Summer Atmodphere based on HIRHAM5 Ensemble Simulations

Author

Sommerfeld, Anja and Sommerfeld, Anja

Abstract

The non-linear behaviour of the atmospheric dynamics is not well understood and makes the evaluation and usage of regional climate models (RCMs) difficult. Due to these non-linearities, chaos and internal variability (IV) within the RCMs are induced, leading to a sensitivity of RCMs to their initial conditions (IC). The IV is the ability of RCMs to realise different solutions of simulations that differ in their IC, but have the same lower and lateral boundary conditions (LBC), hence can be defined as the across-member spread between the ensemble members. For the investigation of the IV and the dynamical and diabatic contributions generating the IV four ensembles of RCM simulations are performed with the atmospheric regional model HIRHAM5. The integration area is the Arctic and each ensemble consists of 20 members. The ensembles cover the time period from July to September for the years 2006, 2007, 2009 and 2012. This time period is chosen because of the melting sea ice and its impact on the atmospheric circulation and the resulting influence on the IV. The specific years are selected due to their minimum summer sea ice area that was achieved within the years. Based on the mean September sea ice area, the years 2007 and 2012 are defined as low ice years and 2006 and 2009 as high ice years. The investigation of these classified years enables an analysis of a relationship between the sea ice conditions and the internally generated ariability. The ensemble members have the same LBC and differ in their IC only. The different IC are arranged by an initialisation time that shifts successively by six hours. Within each ensemble the first simulation starts on 1st July at 00 UTC and the last simulation starts on 5th July at 18 UTC and each simulation runs until 30th September. The analysed time period ranges from 6th July to 30th September, the time period that is covered by all ensemble members. The model runs without any nudging to allow a free development of each simulatio

Published
2015

20. CHAPTER 10: SEA ICE PHYSICS.

Author

Katlein, Christian, Nicolaus, Marcel, Sommerfeld, Anja, Copalorado, Veronica, Tiemann, Louisa, Zanatta, Marco, Schulz, Hannes, and Lange, Benjamin

Published
2018

25. Area of Actions: Equal Opportunities for Women in Physics in Germany.

Author

Sommerfeld, Anja, Kränkl, Susanne, and Sandow, Barbara

Subjects
*WOMEN in physics, *GENDER differences (Psychology), *PHYSICS education, *WOMEN physicists
Abstract

We present the current situation of women in physics in Germany, focusing on women in industry, in academia, and in the German Physical Society (Deutsche Physikalische Gesellschaft e.V.). Progress can be reported, but there is still a long way to go toward equal opportunities. [ABSTRACT FROM AUTHOR]

Published
2015
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27. Arctic budget study of intermember variability using HIRHAM5 ensemble simulations

Author

Sommerfeld, Anja, Nikiema, Oumarou, Rinke, Annette, Dethloff, Klaus, Laprise, René, Sommerfeld, Anja, Nikiema, Oumarou, Rinke, Annette, Dethloff, Klaus, and Laprise, René

Abstract

One of the challenges in evaluating and applying regional climate models (RCMs) is the nonlinear behavior of atmospheric processes, which is still poorly understood. The nonlinearities induce chaos which leads to an internal variability in the model. Therefore, an ensemble of RCM simulations has been run and a budget study for potential temperature has been applied to investigate the internally generated variability. Hence, the physical processes associated with diabatic and dynamical terms inducing the intermember variability have been analyzed. The study is applied over the Arctic on an ensemble of 20 members, differing in their initial conditions, simulated with the RCM HIRHAM5 during summer 2012. This time period is of particular importance because of the melting sea ice and its influence on atmospheric circulation and the resulting effect on the intermember variability. The amplitude of the intermember variability of the simulations fluctuates strongly both temporally and spatially. During the beginning of August 2012 the intermember variability is strongest and coincides with the great Arctic cyclone event. The most important contributions for the intermember variability tendency are the horizontal and vertical “baroclinic” terms. Both terms have largest absolute values along the coastlines of the Arctic Ocean which are associated with the Arctic frontal zone leading to the cyclone maximum over the Arctic Ocean during summer.

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