EGU24-10253, updated on 08 Mar 2024
https://doi.org/10.5194/egusphere-egu24-10253
EGU General Assembly 2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Spatial variation of future trends in Atlantic upwelling cells from CMIP6 models

Raquel Flügel1, Steven Herbette1, Anne Marie Treguier1, Robin Waldman2, and Malcolm Roberts3
Raquel Flügel et al.
  • 1University of Brest, IUEM, LOPS, France
  • 2CNRM, Meteo France, Toulouse, France
  • 3Met Office, FitzRoy Road, Exeter, UK

Eastern Boundary Upwelling Systems (EBUS) are characterised by wind-triggered upwelling of deep waters along the coast. They are hotspots of biological productivity and therefore have a high economic, ecological and social importance. Here we investigate the evolution of the two Atlantic EBUS during the historical period and in a future high-emission scenario in CMIP6 models from two modelling centres, with spatial resolutions ranging from 1° to 1/12° in the ocean. The decomposition of the upwelling systems into subregions reveals differences between the equatorward and poleward parts. Our analysis is focused on the modelled vertical transport, which is shown to be consistent with the wind-derived Ekman index. Integrating the vertical transport provides a synthetic view of the upwelling cells, their strength, depth and distance to the coast. The models show high interannual variability over the 21st century century, which explains why significant trends could only be found in few subregions of the Atlantic EBUS. The results suggest a poleward migration of upwelling systems with climate change and a change of the upwelling cells, rather than the uniform intensification which had been hypothesised by Bakun in 1990.

How to cite: Flügel, R., Herbette, S., Treguier, A. M., Waldman, R., and Roberts, M.: Spatial variation of future trends in Atlantic upwelling cells from CMIP6 models, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10253, https://doi.org/10.5194/egusphere-egu24-10253, 2024.