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101. Surface velocity estimates of the North Indian Ocean from satellite gravity and altimeter missions.

Author

Raj, Roshin P.

Subjects
*OCEAN, *ALTIMETERS, *WINDS, *GEOSTROPHIC wind
Abstract

The circulation in the North Indian Ocean (NIO) is one of the most complex systems compared with other regions of global oceans, mostly due to its interactions with the monsoon winds. In recent years, our ability to measure the ocean's mean dynamic topography (MDT) from space has improved immensely with the availability of satellite gravity measurements from Gravity Recovery and Climate Experiment (GRACE) and Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) missions. The present study uses data from GOCE and GRACE satellite gravity missions together with altimeter data in retrieving the geoid, satellite-only MDT, and surface velocities in the NIO. The study estimates geoid heights of the NIO from all five releases of the direct approach and the time-wise GOCE gravity data. The formal error associated with geoid heights at different resolutions is found to be the lowest for the latest release of direct approach GOCE data. In addition, a new satellite-only MDT is estimated from the direct approach GOCE geoid and the CNES_CLS11 mean sea surface. This MDT corrected to a 20-year time reference is used together with the newly reprocessed sea level anomaly data to estimate absolute dynamic topography and surface geostrophic velocities in the NIO. The total surface velocities computed from the Ekman and geostrophic velocity fields reproduce all major surface currents in the NIO, along with their seasonality. Furthermore, total surface velocity estimates computed here are validated using surface drifters and are found to be highly comparable (difference within ± 10 cm s–1) with more than 170,000 individual surface drifter observations. Finally, the total velocities estimated here are used to examine the variability of the East India Coastal Current. [ABSTRACT FROM AUTHOR]

Published
2017
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102. Monitoring the mesoscale eddies of the Lofoten Basin: i mportance, progress, and challenges.

Author

Raj, Roshin P. and Halo, Issufo

Subjects
*MESOSCALE eddies, *REMOTE sensing, *ALTIMETERS, *ENVIRONMENTAL monitoring
Abstract

The Lofoten Basin is a ‘hot spot’ of intense mesoscale eddy activity in the Nordic Seas. The mesoscale eddies of the Lofoten Basin can be coupled to the heat transport, local climate, and fisheries of the region. During the past two decades, the European satellite missions European Remote Sensing (ERS) satellite and Environmental Satellite (ENVISAT) have played a major part in delivering continuous altimeter measurements over the Lofoten Basin. In recent years, automated eddy detection and tracking methods have revolutionized the long-term monitoring of eddies in the Lofoten Basin from the gridded altimeter data. Another major recent development in this field is the possibility of monitoring eddies on a daily basis from the globally available daily gridded altimeter data. This study assesses the performance of the new daily data compared to the previous weekly data in terms of eddy detection and eddy statistics in the Lofoten Basin. Analysis found that the long-lived eddies detected using the weekly data are counted as separate short-lived eddies when using daily data. In addition, the daily data returns lower eddy intensities (22–40%) with higher eddy radius estimates, which is linked to the anisotropy in the grid spacing of the data. Interestingly, the mean eddy drift in the Lofoten Basin is better represented in the daily data. The daily data shows the westward movement of eddies from the slope current and their subsequent northwestward movement following the topography, before joining the cyclonic drift in the western Lofoten Basin. The study supports the need for a regional gridded data set with high temporal and spatial resolution (in both zonal and meridional scales), in order to optimize the use of satellite altimeter data in the Lofoten Basin. [ABSTRACT FROM PUBLISHER]

Published
2016
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103. Copernicus Marine Service Ocean State Report, Issue 5

Author

von Schuckmann, Karina, Le Traon, Pierre-Yves, Smith, Neville, Pascual, Ananda, Djavidnia, Samuel, Gattuso, Jean-Pierre, Grégoire, Marilaure, Aaboe, Signe, Alari, Victor, Alexander, Brittany E., Alonso-Martirena, Andrés, Aydogdu, Ali, Azzopardi, Joel, Bajo, Marco, Barbariol, Francesco, Batistić, Mirna, Behrens, Arno, Ismail, Sana Ben, Benetazzo, Alvise, Bitetto, Isabella, Borghini, Mireno, Bray, Laura, Capet, Arthur, Carlucci, Roberto, Chatterjee, Sourav, Chiggiato, Jacopo, Ciliberti, Stefania, Cipriano, Giulia, Clementi, Emanuela, Cochrane, Paul, Cossarini, Gianpiero, D'Andrea, Lorenzo, Davison, Silvio, Down, Emily, Drago, Aldo, Druon, Jean-Noël, Engelhard, Georg, Federico, Ivan, Garić, Rade, Gauci, Adam, Gerin, Riccardo, Geyer, Gerhard, Giesen, Rianne, Good, Simon, Graham, Richard, Greiner, Eric, Gundersen, Kjell, Hélaouët, Pierre, Hendricks, Stefan, Heymans, Johanna J., Holt, Jason, Hure, Marijana, Juza, Mélanie, Kassis, Dimitris, Kellett, Paula, Knol-Kauffman, Maaike, Kountouris, Panagiotis, Kõuts, Marilii, Lagemaa, Priidik, Lavergne, Thomas, Legeais, Jean-François, Libralato, Simone, Lien, Vidar S., Lima, Leonardo, Lind, Sigrid, Liu, Ye, Macías, Diego, Maljutenko, Ilja, Mangin, Antoine, Männik, Aarne, Marinova, Veselka, Martellucci, Riccardo, Masnadi, Francesco, Mauri, Elena, Mayer, Michael, Menna, Milena, Meulders, Catherine, Møgster, Jane S., Monier, Maeva, Mork, Kjell Arne, Müller, Malte, Nilsen, Jan Even Øie, Notarstefano, Giulio, Oviedo, José L., Palerme, Cyril, Palialexis, Andreas, Panzeri, Diego, Pardo, Silvia, Peneva, Elisaveta, Pezzutto, Paolo, Pirro, Annunziata, Platt, Trevor, Poulain, Pierre-Marie, Prieto, Laura, Querin, Stefano, Rabenstein, Lasse, Raj, Roshin P., Raudsepp, Urmas, Reale, Marco, Renshaw, Richard, Ricchi, Antonio, Ricker, Robert, Rikka, Sander, Ruiz, Javier, Russo, Tommaso, Sanchez, Jorge, Santoleri, Rosalia, Sathyendranath, Shubha, Scarcella, Giuseppe, Schroeder, Katrin, Sparnocchia, Stefania, Spedicato, Maria Teresa, Stanev, Emil, Staneva, Joanna, Stocker, Alexandra, Stoffelen, Ad, Teruzzi, Anna, Townhill, Bryony, Uiboupin, Rivo, Valcheva, Nadejda, Vandenbulcke, Luc, Vindenes, Håvard, Vrgoč, Nedo, Wakelin, Sarah, and Zupa, Walter

Subjects
14. Life underwater
Abstract

Copernicus Marine Service Ocean State Report, Issue 5

104. Copernicus Marine Service Ocean State Report, Issue 5

Author

von Schuckmann, Karina, Le Traon, Pierre-Yves, Smith, Neville, Pascual, Ananda, Djavidnia, Samuel, Gattuso, Jean-Pierre, Grégoire, Marilaure, Aaboe, Signe, Alari, Victor, Alexander, Brittany E., Alonso-Martirena, Andrés, Aydogdu, Ali, Azzopardi, Joel, Bajo, Marco, Barbariol, Francesco, Batistić, Mirna, Behrens, Arno, Ismail, Sana Ben, Benetazzo, Alvise, Bitetto, Isabella, Borghini, Mireno, Bray, Laura, Capet, Arthur, Carlucci, Roberto, Chatterjee, Sourav, Chiggiato, Jacopo, Ciliberti, Stefania, Cipriano, Giulia, Clementi, Emanuela, Cochrane, Paul, Cossarini, Gianpiero, D'Andrea, Lorenzo, Davison, Silvio, Down, Emily, Drago, Aldo, Druon, Jean-Noël, Engelhard, Georg, Federico, Ivan, Garić, Rade, Gauci, Adam, Gerin, Riccardo, Geyer, Gerhard, Giesen, Rianne, Good, Simon, Graham, Richard, Greiner, Eric, Gundersen, Kjell, Hélaouët, Pierre, Hendricks, Stefan, Heymans, Johanna J., Holt, Jason, Hure, Marijana, Juza, Mélanie, Kassis, Dimitris, Kellett, Paula, Knol-Kauffman, Maaike, Kountouris, Panagiotis, Kõuts, Marilii, Lagemaa, Priidik, Lavergne, Thomas, Legeais, Jean-François, Libralato, Simone, Lien, Vidar S., Lima, Leonardo, Lind, Sigrid, Liu, Ye, Macías, Diego, Maljutenko, Ilja, Mangin, Antoine, Männik, Aarne, Marinova, Veselka, Martellucci, Riccardo, Masnadi, Francesco, Mauri, Elena, Mayer, Michael, Menna, Milena, Meulders, Catherine, Møgster, Jane S., Monier, Maeva, Mork, Kjell Arne, Müller, Malte, Nilsen, Jan Even Øie, Notarstefano, Giulio, Oviedo, José L., Palerme, Cyril, Palialexis, Andreas, Panzeri, Diego, Pardo, Silvia, Peneva, Elisaveta, Pezzutto, Paolo, Pirro, Annunziata, Platt, Trevor, Poulain, Pierre-Marie, Prieto, Laura, Querin, Stefano, Rabenstein, Lasse, Raj, Roshin P., Raudsepp, Urmas, Reale, Marco, Renshaw, Richard, Ricchi, Antonio, Ricker, Robert, Rikka, Sander, Ruiz, Javier, Russo, Tommaso, Sanchez, Jorge, Santoleri, Rosalia, Sathyendranath, Shubha, Scarcella, Giuseppe, Schroeder, Katrin, Sparnocchia, Stefania, Spedicato, Maria Teresa, Stanev, Emil, Staneva, Joanna, Stocker, Alexandra, Stoffelen, Ad, Teruzzi, Anna, Townhill, Bryony, Uiboupin, Rivo, Valcheva, Nadejda, Vandenbulcke, Luc, Vindenes, Håvard, Vrgoč, Nedo, Wakelin, Sarah, and Zupa, Walter

Subjects
14. Life underwater
Abstract

Copernicus Marine Service Ocean State Report, Issue 5

105. The Lofoten Vortex of the Nordic Seas

Author

Raj, Roshin P., Chafik, Léon, Nilsen, J. Even Ø., Eldevik, Tor, Raj, Roshin P., Chafik, Léon, Nilsen, J. Even Ø., and Eldevik, Tor

106. The Copernicus Marine Environment Monitoring Service Ocean State Report

Author

Simon A. Good, Roshin P. Raj, Tanguy Szekely, Yann Drillet, Pierre-Marie Poulain, Charles Desportes, M. Hamon, Irene Perez-Gonzalez, Sandrine Mulet, Lars Axell, Enrique Álvarez-Fanjul, Owen Embury, Gerasimos Korres, Clement Bricaud, Elin Almroth-Rosell, Bruno Buongiorno Nardelli, Jean François Legeais, Quentin Dagneaux, Vidar S. Lien, Shubha Sathyendranath, Angélique Melet, Marie-Fanny Racault, Marcos García Sotillo, Pat Hyder, Aurélien Paulmier, Nathalie Verbrugge, Stephen Dye, Robert J. W. Brewin, Jun She, Mélanie Juza, Antonio G. Ramos, Laurent Parent, Elodie Gutknecht, Isabelle Pujol, Jérôme Gourrion, John Kennedy, Jason Holt, Antonio Bonaduce, Annette Samuelsen, Clotilde Dubois, Stephanie Guinehut, Florent Gasparin, Begoña Pérez-Gómez, Jonathan Tinker, Benoit Meyssignac, Lars-Anders Breivik, Karina von Schuckmann, Peter Sykes, Enda O'Dea, Magdalena Balmaseda, Bengt Karlson, Michael Ablain, Fabrice Hernandez, Gianpiero Cossarini, Alvaro De Pascual, Lena Viktorsson, Emanuela Clementi, Herve Roquet, Urmas Raudsepp, Rosemary Morrow, Giulio Notarstefano, Pierre-Yves Le Traon, Rebecca Reid, Cosimo Solidoro, Joaquín Tintoré, Marie Drevillon, Gilles Garric, Andrea Pisano, Dionysios E. Raitsos, Simona Simoncelli, Eric Greiner, Einar Olason, Coralie Perruche, Hélène Etienne, Fernando Manzano-Munoz, Claudia Fratianni, Nadia Pinardi, Bruno Levier, von Schuckmann, Karina, Le Traon, Pierre-Yve, Alvarez-Fanjul, Enrique, Axell, Lar, Balmaseda, Magdalena, Breivik, Lars-Ander, Brewin, Robert J. W., Bricaud, Clement, Drevillon, Marie, Drillet, Yann, Dubois, Clotilde, Embury, Owen, Etienne, Hélène, Sotillo, Marcos García, Garric, Gille, Gasparin, Florent, Gutknecht, Elodie, Guinehut, Stéphanie, Hernandez, Fabrice, Juza, Melanie, Karlson, Bengt, Korres, Gerasimo, Legeais, Jean-Françoi, Levier, Bruno, Lien, Vidar S., Morrow, Rosemary, Notarstefano, Giulio, Parent, Laurent, Pascual, Álvaro, Pérez-Gómez, Begoña, Perruche, Coralie, Pinardi, Nadia, Pisano, Andrea, Poulain, Pierre-Marie, Pujol, Isabelle M., Raj, Roshin P., Raudsepp, Urma, Roquet, Hervé, Samuelsen, Annette, Sathyendranath, Shubha, She, Jun, Simoncelli, Simona, Solidoro, Cosimo, Tinker, Jonathan, Tintoré, Joaquín, Viktorsson, Lena, Ablain, Michael, Almroth-Rosell, Elin, Bonaduce, Antonio, Clementi, Emanuela, Cossarini, Gianpiero, Dagneaux, Quentin, Desportes, Charle, Dye, Stephen, Fratianni, Claudia, Good, Simon, Greiner, Eric, Gourrion, Jerome, Hamon, Mathieu, Holt, Jason, Hyder, Pat, Kennedy, John, Manzano-Muñoz, Fernando, Melet, Angélique, Meyssignac, Benoit, Mulet, Sandrine, Buongiorno Nardelli, Bruno, O’Dea, Enda, Olason, Einar, Paulmier, Aurélien, Pérez-González, Irene, Reid, Rebecca, Racault, Marie-Fanny, Raitsos, Dionysios E., Ramos, Antonio, Sykes, Peter, Szekely, Tanguy, and Verbrugge, Nathalie

Subjects
0106 biological sciences, Arctic sea ice decline, State of the ocean, 010504 meteorology & atmospheric sciences, Effects of global warming on oceans, Antarctic sea ice, Oceanografi, hydrologi och vattenresurser, Oceanography, Ocean reporting, 01 natural sciences, Oceanography, Hydrology and Water Resources, Copernicus Marine Environment Monitoring Service, Sea ice, Operational oceanography, Ocean climate variability, 14. Life underwater, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, 010604 marine biology & hydrobiology, Arctic ice pack, Sea surface temperature, 13. Climate action, Climatology, Environmental science, Thermohaline circulation, Ocean variability, Ocean monitoring, Ocean heat content
Abstract

The Copernicus Marine Environment Monitoring Service (CMEMS) Ocean State Report (OSR) provides an annual report of the state of the global ocean and European regional seas for policy and decision-makers with the additional aim of increasing general public awareness about the status of, and changes in, the marine environment. The CMEMS OSR draws on expert analysis and provides a 3-D view (through reanalysis systems), a view from above (through remote-sensing data) and a direct view of the interior (through in situ measurements) of the global ocean and the European regional seas. The report is based on the unique CMEMS monitoring capabilities of the blue (hydrography, currents), white (sea ice) and green (e.g. Chlorophyll) marine environment. This first issue of the CMEMS OSR provides guidance on Essential Variables, large-scale changes and specific events related to the physical ocean state over the period 1993–2015. Principal findings of this first CMEMS OSR show a significant increase in global and regional sea levels, thermosteric expansion, ocean heat content, sea surface temperature and Antarctic sea ice extent and conversely a decrease in Arctic sea ice extent during the 1993–2015 period. During the year 2015 exceptionally strong large-scale changes were monitored such as, for example, a strong El Niño Southern Oscillation, a high frequency of extreme storms and sea level events in specific regions in addition to areas of high sea level and harmful algae blooms. At the same time, some areas in the Arctic Ocean experienced exceptionally low sea ice extent and temperatures below average were observed in the North Atlantic Ocean.

Published
2016

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