You are here: Home page » Team

Simon Wett

  • Tel: +49 (0)421 218-62159
  • Fax: +49 (0)421 218-62165
  • Email: simon.wett [at] uni-bremen.de

Research Interests

  • Observed variability of the Atlantic Meridional Overturning Circulation (AMOC) in the North Atlantic
  • Analyzing In-situ and remote observations
  • AMOC variability in high-resolution ocean models
  • Meridional Connectivity of observed and modeled AMOC variability
  • Formation and transport of water masses in the North Atlantic
PhD Projekt


The Atlantic Meridional Overturning Circulation (AMOC) is the main driver of northward oceanic volume and heat transport in the Atlantic. Due to its definition via the streamfunction the exact calculation of the AMOC requires knowledge of the full velocity field. Since the early 2000s, hydrographic sections across the Atlantic at 47 deg North and continuous current measurements from moored instruments at specific locations are available. From these observations AMOC components can be estimated. However, the spatial resolution of current measurements is coarse and shipbased hydrographic sections are mostly done only once a year. Also, the observational timeseries still remain too short to come to conclusions about decadal trends in the AMOC variability. Thus, today our knowledge about the role of the AMOC in the global climate system is mainly based on model simulations. Comparing these model simulations against observations remains an important task to accurately predict the future of the AMOC and adapt to changes.

This project will conduct a comparison of the AMOC in the North Atlantic from observations at 47 deg North and a high-resolution ocean model. This comparison will help assessing different methods of estimating the AMOC strength from observations. Another part of the analysis will focus on the role of Labrador Sea Water (LSW) formation, a main component of the AMOC. Changes in LSW formation have repercussions for the AMOC: in most ocean-ice and climate models, a stronger LSW ventilation is related to larger than normal air-sea heat flux anomalies over the subpolar North Atlantic and to an increased AMOC transport. This project will test this hypothesis in observations and high-resolution ocean models.
Curriculum Vitae  
since 09/2019 Scientist (PhD student), Institute of Environmental Physics and MARUM – Center for Marine Environmental Sciences, University of Bremen, Germany
2015-2019 Studies in Physical Oceanography, Universität Hamburg, Degree: M.Sc.
2012-2015 Studies in Geophysics/Oceanography, Universität Hamburg, Degree: B.Sc.
Projects  
since 09/2019 Member of the international Research Training Group ArcTrain
since 10/2019 Member of the Bremen International Graduate School for Marine Sciences GLOMAR
Publications
Wett, S., M. Rhein, D. Kieke, C. Mertens, and M. Moritz (2023), Meridional connectivity of a 25-year observational AMOC record at 47°N. Geophysical Research Letters, 50, e2023GL103284, doi:10.1029/2023GL103284.
Kieke, D., K. Bulsiewicz, C. Gapp, Y. Hinse, O. Huhn, B. Holanda, A. Hunkemöller, S. Kinne, M. Köllner, L. Krisztian, O. Krüger, I. Leimann, M. Pöhlker, A. Schneehorst, A. Smirnov, R. Steinfeldt, M. Stelzner, J. Stiehler, T. Svensson, S. Wett, and K. N. Wiegand (2021), AMOC Components at 47°N, Cruise No. M164 (GPF-19-1-105), June 23 - July 31, 2020, Emden (Germany) - Emden (Germany), METEOR-Berichte, Gutachterpanel Forschungsschiffe, doi:10.48433/cr_m164.
Wett, S., 2018. The Impacts of Sudden Stratospheric Warmings on the Subpolar North Atlantic, Master’s Thesis, Universität Hamburg
Jochumsen, K., D. Hainbucher, L. Umlauf, J. Carpenter, H. Mashayekh Poul, R. North, P. Holtermann, J. Dräger-Dietel, A. Welsch, T. Heene, M. Sass, M. Specht, S. Wett, A. Rochner, A. Wünsche, M. Rotermund, L. Schultze, L. Zeigermann, T. Wasilewski, N. Verch, C. Gillner, S. Shilongo, and A. Raeke, 2017. Submesoscale dynamics at the Benguela eastern boundary upwelling system - frontal instabilities, mixed layer eddies and upwelling filaments, Cruise No. M132, 15th November - 11th December 2016, Walvis Bay - Cape Town. METEOR-Berichte, Gutachterpanel Forschungsschiffe, doi:10.2312/cr_m132
Kieke, D., W. Böke, S. Büttner, K. Bulsiewicz, C. Danek, T. Hempel, D. Khordakova, B. Mirau, A. Rochner, A. Roessler, N. Rohlfs, A. Schneehorst, R. Steinfeldt, P. Sültenfuß, H.-H. Uhde, S. Wett, K. Wiegand, and F. Wischnewski, 2018. Subpolar Gyre Variability, Cruise No. MSM53, March 31 - May 09, 2016, Kiel (Germany) - St. John's (Canada). MARIA S. MERIAN-Berichte, DFG-Senatskommission für Ozeanographie, doi:10.2312/cr_msm53.
Kieke, D., R. Barbosa Primon, K. Bulsiewicz, C. Gjerdrum, K. Jochumsen, J. Meyerjürgens, M. Moritz, V. Müller, C. Rieper, A. Rochner, P. Sültenfuß, L. Tiemann, E. Varotsou, A. Welsch, S. Wett, K. Wiegand, J. Winkel, and F. Wischnewski, 2016. FLEPVAR 2015 (Variability in Flemish Pass), Cruise No. MSM42, May 2 - May 22, 2015 - Bermuda - St. John's (Canada). MARIA S. MERIAN-Berichte, DFG-Senatskommission für Ozeanographie, doi:10.2312/cr_msm42.
Wett, S., 2015. Estimating the Wind Energy Input into the Ocean from Satellite Measurements (in German), Bachelor’s Thesis
Conference Contributions
Wett, S., M. Rhein, D. Kieke, C. Mertens, M. Moritz (2023), Meridional Connectivity of a 25-year Observational AMOC record at 47°N, AMOC workshop "Meeting AMOC Observation Needs in a Changing Climate", Hamburg (talk)
Wett, S., M. Rhein, D. Kieke, C. Mertens, M. Moritz (2023), Meridional Connectivity of a 25-year Observational AMOC record at 47°N, EGU General Assembly, Vienna (talk)
Wett, S., M. Rhein, C. Mertens, H. Nowitzki, M. Moritz, D. Kieke (2022), An AMOC Timeseries at 47°N Based on Observations, ArcTrain Annual Meeting 2022, Orford, Canada (PICO talk and Poster)
Wett, S., M. Rhein, C. Mertens, H. Nowitzki, M. Moritz, D. Kieke (2022), An AMOC Timeseries at 47°N Based on Observations, Ocean Sciences Meeting, Online (talk)
Wett, S., M. Rhein, C. Mertens, H. Nowitzki, M. Moritz, D. Kieke (2021), An AMOC Timeseries at 47°N Based on Observations, ArcTrain Annual Meeting 2021, Etelsen, Germany (PICO talk and Poster)
Wett, S., M. Rhein, A. Biastoch, C. Böning, K. Getzlaff (2021), AMOC Components at 47°N in the Last Decades in Observations and a Realization of the VIKING20X High-Resolution Ocean Model, Future Directions in Basin and Global High-resolution Ocean Modelling, Online (talk)
Wett, S., M. Rhein, C. Mertens, H. Nowitzki, M. Moritz, D. Kieke (2021), Ideas on Calculating the AMOC at 47°N from Observations, EGU General Assembly, Online (PICO talk and poster)
Wett, S., M. Rhein, A. Biastoch, C. Böning, K. Getzlaff (2021), AMOC Evolution at 47°N in the last decades in a High-Resolution Ocean model and Observations, Arctic Science Summit Week, Online (poster)
Wett, S., M. Rhein, A. Biastoch, K. Getzlaff (2020), The Recent Decline of the Atlantic Meridional Overturning Circulation - How Strong is it Really?, ArcTrain Annual Meeting 2020, Online (PICO talk and Poster)
Participation in Scientific Cruises
RV Meteor, M164 Subpolar North Atlantic Jun - Jul 2020 Emden, Germany - Emden, Germany
RV Maria S. Merian, MSM-76 Denmark Strait and Greenland Shelf Jun - Aug 2018 Reykjavik, Iceland - Logyearbyen, Norway
RV Meteor, M132 Benguela Upwelling System Nov - Dec 2016 Walvis Bay, Namibia - Capetown, South Africa
RV Maria S. Merian, MSM-53 Subpolar North Atlantic Mar - May 2016 Kiel, Germany - St. John's, Canada
RV Maria S. Merian, MSM-42 Newfoundland Basin May 2015 Bemuda - St. John's, Canada