Jr.-Prof. Dr. Joakim Kjellsson


Research Division 1: Ocean Circulation & Climate Dynamics
ME Marine Meteorology

Raum: 4.306
Telefon: +49 431 600-4057
E-Mail: jkjellsson(at)geomar.de

Adresse: Wischhofstrasse 1-3 24148 Kiel

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Research interests

  • Climate change adaptation (Northern European Enclosure Dam)
  • Extreme weather events
  • Air-sea interactions 
  • Kinetic energy budgets in ocean models and the impact of horizontal resolution
  • Tracing air- and water masses using Lagrangian trajectories


  • 2005-2009: Undergraduate studies in Meteorology at Stockholm University
  • 2009-2014: PhD studies in Atmospheric Sciences & Oceanography at Stockholm University
  • 2014-2016: Postdoc at British Antarctic Survey, Cambridge, UK
  • 2016-2017: Postdoc at Atmospheric, Oceanic and Planetary Physics, University of Oxford, UK
  • 2017-2019: Postdoc at GEOMAR
  • 2019- : W1 Junior Professor in Meteorology 

Recent research

Kjellsson, J., Park, W. Multi-centennial variability of AMOC variability in the FOCI-OpenIFS climate model. In review for Nat. Communications Earth & Environment

Kjellsson, J., et al. Reducing Southern Ocean surface biases in the FOCI climate model. In review for Journal of Advances in Modelling Earth Systems. 

Ayres, H., Ferreira, D., Park, W, Kjellsson, J., Ödalen, M. (2024) A comparison of the atmospheric response to the Weddell Sea polynya in AGCMs of varying resolutions. Weather Clim. Dynam., 5, 805–820, doi: 10.5194/wcd-5-805-2024

Savita, A., Kjellsson, J., Pilch-Kedzierski, R. (2024) ECMWF-OpenIFS climate sensitivity to horizontal resolutions and model time step. Geoscientific Model Development. 17, 1813–1829, doi: 10.5194/gmd-2023-101

Krüger, J., Kjellsson, J., Pilch Kedzerski, R., Claus, M. (2023) Connecting North Atlantic SST variability to European heat events in recent decades. Tellus A: Dynamic Meteorology and Oceanography, 75(1), 358-374, doi: 10.16993/tellusa.3235

Latif, M., Bayr, T., Kjellsson, J.,  Lübbecke, J.F, Martin, T., Nnamchi, H.C., Park, W., Savita, A., Sun, J., Dommenget, D. (2023) Strengthening atmospheric circulation and trade winds slowed tropical Pacific surface warming. Nat. Communications Earth & Environment, 4, doi: 10.1038/s43247-023-00912-4

Streffing, J., …, Kjellsson, J. et al.  (2022) AWI-CM3 coupled climate model: description and evaluation experiments for a prototype post-CMIP6 model. Geosci. Mod. Dev., 15, 6399-6427, doi: 10.5194/gmd-15-6399-2022


Physics of the Earth System, Bachelor

  • Introduction to Meteorology
  • Practical Meteorology + Excursion

Climate Physics Programme, Master

  • Oceanography-Meteorology Literature Seminar
  • Data Analysis & Statistics
  • Climate Modelling
  • Tropospheric Dynamics and Physics
  • Meteorology Lunch Seminar


ROADMAP (The Role of Ocean Dynamics and Ocean-Atmosphere Interactions in Driving Climate Variations).
JPI Oceans & Climate (via BMBF). WP4 co-lead. GEOMAR share: € 360,648. roadmap.rd.ciencias.ulisboa.pt

SCENIC (Storyline Scenarios of Extreme Weather, Climate, and Environmental Events along with their Impacts in a Warmer World).
Helmholtz PoF IV Innovation Pool. earthenvironment. helmholtz.de/changing-earth/innopool-projects/

SO-CHIC (Southern Ocean Carbon and Heat Impact on Climate)
EU Horizon 2020. GEOMAR share: €356,250. www. sochic-h2020.eu/


Abhishek Savita, 2021 - (2024), Oceanic influence on atmospheric circulation

Sayantani Ojha, 2022 - (2025), Impact of Greenland melting on atmospheric extremes

Malin Ödalen, 2023 - (2024), Southern Ocean heat and carbon uptake


PhD students

Julian Krüger, 2020 - 2023, On the Role of North Atlantic Sea Surface Temperatures for European Heat Events

Sedat Gözlet, 2021 - (2024), Atmospheric Extreme Events in Future Climates

Médéric StPierre, 2021 - (2024), Climate-projection uncertainties in grand model ensemble [co-supervisor]

Yingxue Liu, 2022 - (2026), Extreme weather events in present and future climates

Qi Zhang, 2022 - (2026), Analyzing extreme temperature under global warming: Trends, Models, and Mechanisms

Master theses

Tabea Rahm, 2023, How will the dominant weather regimes change under the influence of climate warming? oceanrep.geomar.de/id/eprint/58633

Lukas Schreiber, 2023, What Drives the Salinity in the Global Ocean under Changing Climate Forcing? oceanrep.geomar.de/id/eprint/58629 [co-supervisor]

Sebastian Bubmann, 2023, Is statistical downscaling of seasonal precipitation forecasts worth the effort?

Nicolas Dettling, 2021, Response of atmospheric heat and moisture transports to anthropogenic climate forcing, oceanrep.geomar.de/id/eprint/54674

Bachelor theses

Finn Könecke, 2024, What is the fingerprint of AMOC variability and its trends?, oceanrep.geomar.de/id/eprint/60220

Stefanie Brechtelsbauer, 2023, Extreme Greenland Ice Sheet melt events in a warmer world: A storyline approach, [co-supervisor]

Katharina Schmitt, 2023, Convective and Gravity Wave Momentum Transport during EUREC4A, oceanrep.geomar.de/id/eprint/58491 [co-supervisor]

Thies Johnsen, 2023, Impact of Ocean Model Resolution on the Representation of North Atlantic and European Blocking in the FOCI-OpenIFS Model, oceanrep.geomar.de/id/eprint/59267, [co-supervisor]

Lasse Kummer, 2023, Representation of double-gyre circulations in ocean models of varying horizontal resolutions, oceanrep.geomar.de/id/eprint/58944  

Paula Damke, 2022, Effect of Seasonal Sea Ice on Southern Ocean Mesoscale Eddy Activity in a Climate Model, oceanrep.geomar.de/id/eprint/57354, [co-supervisor]

Julia Noack, 2022, How do mesoscale ocean dynamics affect Antarctic Circumpolar Current strength in climate models?, oceanrep.geomar.de/id/eprint/56735, [co-supervisor]

Nana Hocke, 2022, Representation of jet stream trends in atmospheric models, oceanrep.geomar.de/id/eprint/57353

Leah Kanzler, 2022, How do atmosphere models reproduce observed extreme precipitation events?, oceanrep.geomar.de/id/eprint/56734

Daniel Kaufmann, 2022, Veränderung des Schneefalls über Europa in Klimamodellsimulationen, oceanrep.geomar.de/id/eprint/57352

Sebastian Bubmann, 2021, Rainfall patterns in Port Moresby, Papua New Guinea,

Alexander Schmitz, 2021, Veränderung der Niederschlagsverteilung über Europa in CMIP6 Modellen [co-supervisor]

Corinna Buder, 2020, Impact of a Northern European Enclosure Dam on North Atlantic Climate, oceanrep.geomar.de/id/eprint/51118

Johanna Knauf, 2020, Impact of ocean resolution on storms in the North Atlantic region, oceanrep.geomar.de/id/eprint/51117

Nils Niebaum, 2020, Trends in heat Stress over Europe, oceanrep.geomar.de/id/eprint/51346

Lisa Kaspar, 2020, Einfluss von ENSO auf die Variabilität im Südlichen Ozean, oceanrep.geomar.de/id/eprint/54682 [co-supervisor]

Jakob Deutloff, 2020, Drivers of Climate-Model Biases in Antarctic Circumpolar Current Strength, oceanrep.geomar.de/id/eprint/51119

Berenike Rappat, 2019, Klimatvariabilität im Südlichen Ozean aus Beobachtungen,