Articles | Volume 11, issue 3
https://doi.org/10.5194/os-11-483-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/os-11-483-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
30 Jun 2015
Research article |
| 30 Jun 2015
Decadal variability and trends of the Benguela upwelling system as simulated in a high-resolution ocean simulation
Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
E. Zorita
Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
B. Hünicke
Helmholtz-Zentrum Geesthacht, Institute of Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
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Sitar Karabil, Eduardo Zorita, and Birgit Hünicke
Earth Syst. Dynam., 8, 1031–1046, https://doi.org/10.5194/esd-8-1031-2017, https://doi.org/10.5194/esd-8-1031-2017, 2017
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We statistically analysed the mechanisms of the variability in decadal sea-level trends for the whole Baltic Sea basin over the last century. We used two different sea-level data sets and several climatic data sets. The results of this study showed that precipitation has a lagged effect on decadal sea-level trend variations from which the signature of atmospheric effect is removed. This detected underlying factor is not connected to oceanic forcing driven from the North Atlantic region.
Johann H. Jungclaus, Edouard Bard, Mélanie Baroni, Pascale Braconnot, Jian Cao, Louise P. Chini, Tania Egorova, Michael Evans, J. Fidel González-Rouco, Hugues Goosse, George C. Hurtt, Fortunat Joos, Jed O. Kaplan, Myriam Khodri, Kees Klein Goldewijk, Natalie Krivova, Allegra N. LeGrande, Stephan J. Lorenz, Jürg Luterbacher, Wenmin Man, Amanda C. Maycock, Malte Meinshausen, Anders Moberg, Raimund Muscheler, Christoph Nehrbass-Ahles, Bette I. Otto-Bliesner, Steven J. Phipps, Julia Pongratz, Eugene Rozanov, Gavin A. Schmidt, Hauke Schmidt, Werner Schmutz, Andrew Schurer, Alexander I. Shapiro, Michael Sigl, Jason E. Smerdon, Sami K. Solanki, Claudia Timmreck, Matthew Toohey, Ilya G. Usoskin, Sebastian Wagner, Chi-Ju Wu, Kok Leng Yeo, Davide Zanchettin, Qiong Zhang, and Eduardo Zorita
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Maria Pyrina, Sebastian Wagner, and Eduardo Zorita
Clim. Past, 13, 1339–1354, https://doi.org/10.5194/cp-13-1339-2017, https://doi.org/10.5194/cp-13-1339-2017, 2017
Svenja E. Bierstedt, Birgit Hünicke, Eduardo Zorita, and Juliane Ludwig
Earth Syst. Dynam., 8, 639–652, https://doi.org/10.5194/esd-8-639-2017, https://doi.org/10.5194/esd-8-639-2017, 2017
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We statistically analyse the relationship between the structure of migrating dunes in the southern Baltic and the driving wind conditions over the past 26 years, with the long-term aim of using migrating dunes as a proxy for past wind conditions at an interannual resolution.
Juan José Gómez-Navarro, Eduardo Zorita, Christoph C. Raible, and Raphael Neukom
Clim. Past, 13, 629–648, https://doi.org/10.5194/cp-13-629-2017, https://doi.org/10.5194/cp-13-629-2017, 2017
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This contribution aims at assessing to what extent the analogue method, a classic technique used in other branches of meteorology and climatology, can be used to perform gridded reconstructions of annual temperature based on the limited information from available but un-calibrated proxies spread across different locations of the world. We conclude that it is indeed possible, albeit with certain limitations that render the method comparable to more classic techniques.
Xing Yi and Eduardo Zorita
Clim. Past Discuss., https://doi.org/10.5194/cp-2016-124, https://doi.org/10.5194/cp-2016-124, 2016
Revised manuscript not accepted
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In this paper we study the upwelling in the Arabian Sea simulated in two Earth System Models for the last millennium and for the 21st century. Revealing a negative long-term trend due to the model orbital forcing, the upwelling over the last millennium is strongly correlated with the SST, the Indian summer Monsoon and the G.bulloides abundance observed in the sediment records. In the future scenarios the warming of the sea water tends to stabilize the surface layer and hinder the upwelling.
Nele Tim, Eduardo Zorita, Birgit Hünicke, Xing Yi, and Kay-Christian Emeis
Ocean Sci., 12, 807–823, https://doi.org/10.5194/os-12-807-2016, https://doi.org/10.5194/os-12-807-2016, 2016
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The impact of external climate forcing on the four eastern boundary upwelling systems is investigated for the recent past and future. Under increased radiative forcing, upwelling-favourable winds should strengthen due to unequal heating of land and oceans. However, coastal upwelling simulated in ensembles of climate simulations do not show any imprint of external forcing neither for the past millennium nor for the future, with the exception of the strongest future scenario.
Svenja E. Bierstedt, Birgit Hünicke, Eduardo Zorita, Sebastian Wagner, and Juan José Gómez-Navarro
Clim. Past, 12, 317–338, https://doi.org/10.5194/cp-12-317-2016, https://doi.org/10.5194/cp-12-317-2016, 2016
X. Yi, B. Hünicke, N. Tim, and E. Zorita
Ocean Sci. Discuss., https://doi.org/10.5194/osd-12-2683-2015, https://doi.org/10.5194/osd-12-2683-2015, 2015
Revised manuscript not accepted
Short summary
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In this paper, we use the vertical water mass transport data provided by a high-resolution global ocean simulation to study the western Arabian Sea coastal upwelling system. Our results show that: 1). no significant long-term trend is detected in the upwelling time series. 2). the impact of Indian summer monsoon on the simulated upwelling is weak. 3). the upwelling is strongly affected by the sea level pressure gradient and the air temperature gradient.
J. J. Gómez-Navarro, O. Bothe, S. Wagner, E. Zorita, J. P. Werner, J. Luterbacher, C. C. Raible, and J. P Montávez
Clim. Past, 11, 1077–1095, https://doi.org/10.5194/cp-11-1077-2015, https://doi.org/10.5194/cp-11-1077-2015, 2015
J. A. Santos, M. F. Carneiro, A. Correia, M. J. Alcoforado, E. Zorita, and J. J. Gómez-Navarro
Clim. Past, 11, 825–834, https://doi.org/10.5194/cp-11-825-2015, https://doi.org/10.5194/cp-11-825-2015, 2015
J. J. Gómez-Navarro, J. P. Montávez, S. Wagner, and E. Zorita
Clim. Past, 9, 1667–1682, https://doi.org/10.5194/cp-9-1667-2013, https://doi.org/10.5194/cp-9-1667-2013, 2013
G. Esnaola, J. Sáenz, E. Zorita, A. Fontán, V. Valencia, and P. Lazure
Ocean Sci., 9, 655–679, https://doi.org/10.5194/os-9-655-2013, https://doi.org/10.5194/os-9-655-2013, 2013
O. Bothe, J. H. Jungclaus, D. Zanchettin, and E. Zorita
Clim. Past, 9, 1089–1110, https://doi.org/10.5194/cp-9-1089-2013, https://doi.org/10.5194/cp-9-1089-2013, 2013
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Short summary
The atmospheric drivers of the Benguela upwelling systems and its variability are statistically analysed with an ocean-only simulation over the last decades. Atmospheric upwelling-favourable conditions are southerly wind/wind stress, a strong subtropical anticyclone, and an ocean-land sea level pressure gradient as well as a negative ENSO and a positive AAO phase. No long-term trends of upwelling and of ocean-minus-land air pressure gradients, as supposed by Bakun, can be seen in our analysis.
The atmospheric drivers of the Benguela upwelling systems and its variability are statistically...
