Picture of Cara Nissen
Research Associate
• Ocean biogeochemical cycles • Bio-physical interactions • Ocean modeling
Atmospheric and Oceanic Sciences

Ocean Biogeochemistry Research Group


Modeling of Southern Ocean carbon and nutrient cycles under present and future climates; understanding how ocean circulation, the cryosphere and biology interact to shape high-latitude biogeochemical cycles.


  • PhD: ETH Zürich, Switzerland, 2019
  • MSc: University of Bergen, Norway, 2014
  • BSc: University of Kiel/GEOMAR, Germany, 2012



Nissen, C., N. S. Lovenduski, M. Maltrud, A. Gray, Y. Takano, K. Falcinelli, J. Sauvé, K. Smith (2024): Using synthetic float capabilities in E3SMv2 to assess spatio-temporal variability in ocean physics and biogeochemistry. In review in Geoscientific Model Development. Preprint available at: https://doi.org/10.5194/gmd-2023-220.

Brooks, C., S. Stammerjohn, G. Ballard, A. DuVivier, E. Hofman, M. LaRue, C. Nissen, J. Pan, N. Walker, G. Watters, J. Weller (2024): Research and monitoring in remote large-scale marine protected areas: the Ross Sea region as a model system. In review in Conservation Letters

Gorte, T., Lovenduski, N. S., Nissen, C., Lenaerts, J. T. M., J. Weiss (2024): The nonlinear and distinct responses of ocean heat content and anthropogenic carbon to ice sheet freshwater discharge in a warming climate. In reivew in Earth's Future. Preprint available at http://doi.org/10.22541/essoar.170688946.68286030/v1.

Heinze, C., ..., Nissen, C., ... (2024): Reviews and syntheses: Abrupt ocean biogeochemical change under human-made climatic forcing – warming, acidification, and deoxygenation. In review in Biogeosciences. Preprint available at https://bg.copernicus.org/preprints/bg-2023-182/

Nagwekar, T., C. Nissen, J. Hauck (2024): Ocean alkalinity enhancement in deep and bottom water formation regions under low and high emission pathways. In review in Earth’s Future.

Oziel, L., Gürses, Ö., Torres-Valdes, S., Hoppe, C., Rost, B., Karakus, O., Danek, C., Juhls, B., Voelker, C.,  Koldunov, N., Wang, Q., Iversen, M., Koch, B., Nissen, C., Hauck, J. (2024): Climate Change and terrigenous inputs decrease the efficiency of the future Arctic Ocean’s biological carbon pump, in review in Nature Climate Change. Preprint available at  https://doi.org/10.21203/rs.3.rs-3867146/v1.

(16) Bunsen, F., Nissen, C. and Hauck, J., 2024: The impact of recent climate change on the ocean carbon sink. In review in Geophysical Research Letters, 51, e2023GL107030. DOI: 10.1029/2023GL107030.

(15) Nissen, C., Timmermann, R., van Caspel, M., and Wekerle, C., 2024: Altered Weddell Sea warm- and dense-water pathways in response to 21st-century climate change. Ocean Science, 20, 85–101. DOI: 10.5194/os-20-85-2024

(14) Resplandy,  L. A. Hogikyan,  J. D. Müller,  R. G. Najjar,  H. W. Bange,  D. Bianchi,  T. Weber,  W.-J. Cai, S. C. Doney,  K. Fennel,  M. Gehlen,  J. Hauck,  F. Lacroix,  P. Landschützer,  C. Le Quéré,  A. Roobaert,  J. Schwinger,  S. Berthet,  L. Bopp,  T. T. T. Chau,  M. Dai,  N. Gruber,  T. Ilyina,  A. Kock, M. Manizza,  Z. Lachkar,  G. G. Laruelle,  E. Liao,  I. D. Lima,  C. Nissen,  C. Rödenbeck,  R. Séférian, K. Toyama,  H. Tsujino,  P. Regnier, 2024: A Synthesis of Global Coastal Ocean Greenhouse Gas Air-sea fluxesGlobal Biogeochemical Cycle, 38, e2023GB007803. DOI: 10.1029/2023GB007803

(13) Nissen, C., Lovenduski, N. S., Brooks, C. M., Hoppema, M., Timmermann, R., Hauck, J., 2024: Severe 21st-century ocean acidification in Antarctic Marine Protected Areas. Nature Communications, 15, 259. DOI: 10.1038/s41467-023-44438-x.

(12) Hauck, J.,Gregor, L., Nissen, C., Patara, L., Hague, M., Mongwe, P., Bushinsky, S., Doney, S. C., Gruber, N., Le Quéré, C., Manizza, M., Mazloff, M., Monteiro, P. M. S., Terhaar, J., 2023: The Southern Ocean carbon cycle 1985-2018: mean, seasonal cycle, trends, and storageGlobal Biogeochemical Cycles, 37, e2023GB007848. DOI: 10.1029/2023GB007848

(11) Gorte, T., Lovenduski, N. S., Nissen, C., Lenaerts, J. T. M., 2023: Antarctic Ice Sheet freshwater discharge drives substantial Southern Ocean changes over the 21st century. Geophysical Research Letters, 50, e2023GL104949. DOI: 10.1029/2023GL104949

(10) DeVries, T., K. Yamamoto, R. Wanninkhof, N. Gruber, J. Hauck, J. D. Müller, L. Bopp, D. Carroll, B. Carter, T. T. T. Chau, S. Doney, M. Gehlen, L. Gloege, L. Gregor, S., Henson, J. H. Kim, Y. Iida, T. Ilyina, P. Landschützer, C. Le Quéré, D. Munro, C. Nissen, L. Patara, F. Perez, L. Resplandy, K. Rodgers, J. Schwinger, R. Séférian, V. Sicardi, J. Terhaar, J., Trinanes, H. Tsujino, A., Watson, S. Yasunaka, and J., Zeng, 2023: Magnitude, trends, and variability of the global ocean carbon sink from 1985-2018Global Biogeochemical Cycles, 37, e2023GB007780, DOI: 10.1029/2023GB007780

(9) Nissen, C., Timmermann, R., Hoppema, M., Hauck, J., 2023: A regime shift on Weddell Sea continental shelves with local and remote physical-biogeochemical implications is avoidable in a 2°C scenario. Journal of Climate, 36(19), 6613-6630. DOI: 10.1175/JCLI-D-22-0926.1

(8) Seifert, M., Nissen, C., Rost, B., Vogt, M., Völker, C., Hauck, J., 2023: Interaction matters: Bottom-up driver interdependencies alter the projected response of phytoplankton communities to climate change. Global Change Biology, 00, 1– 25. DOI: 10.1111/gcb/16799

(7) Hauck, J., Nissen, C., Landschützer, P., Rödenbeck, C., Bushinsky, S., & Olsen, A. 2023: Sparse observations induce large biases in estimates of the global ocean CO2 sink: an ocean model subsampling experiment. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 381(2249). DOI: 10.1098/rsta.2022.0063

(6) Seifert, M., Nissen, C., Rost, B., Hauck, J. 2022: Cascading effects augment the direct impact of CO2 on phytoplankton growth in a biogeochemical model. Elementa: Science of the Anthropocene, 10 (1): 00104, DOI: 10.1525/elementa.2021.00104 

(5) Nissen, C., Timmermann, R., Hoppema, M., Gürses, Ö., Hauck, J., 2022: Abruptly attenuated carbon sequestration with Weddell Sea dense waters by 2100. Nature Communications, 13: 3402. DOI: 10.1038/s41467-022-30671-3

(4) Nissen, C., Vogt, M., 2021: Factors controlling the competition between Phaeocystis and diatoms in the Southern Ocean and implications for carbon export fluxes. Biogeosciences, 18(1): 251-283. DOI: 10.5194/bg-18-251-2021

(3) Nissen, C., Gruber, N., Münnich, M., Vogt, M., 2021: Southern Ocean phytoplankton community structure as a gatekeeper for global nutrient biogeochemistry. Global Biogeochemical Cycles, 35(8): e2021GB006991. DOI: 10.1029/2021GB006991

(2) Krumhardt, K., Lovenduski, N., Long, M. C., Levy, M., Lindsay, K., Moore, J. K., Nissen, C., 2019: Coccolithophore growth and calcification in an acidified ocean: Insights from Community Earth System Model simulations. Journal of Advances in Modeling Earth Systems, 11(5): 1418-1437. DOI: 10.1029/2018MS001483

(1) Nissen, C., Vogt, M., Münnich, M., Gruber, N., Haumann, F. A., 2018: Factors controlling coccolithophore biogeography in the Southern Ocean. Biogeosciences, 15(22): 6997-7024. DOI: 10.5194/bg-15-6997-2018