EGU21-12580
https://doi.org/10.5194/egusphere-egu21-12580
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Variability of the North Atlantic Oscillation in the 20th century

André Düsterhus1, Leonard Borchert2, Vimal Koul3,4, Holger Pohlmann5,6, and Sebastian Brune4
André Düsterhus et al.
  • 1Irish Climate Analysis and Research UnitS (ICARUS), Department of Geography, Maynooth University, Maynooth, Ireland (andre.duesterhus@mu.ie)
  • 2LOCEAN Laboratory, Institut Pierre Simon Laplace (IPSL), Sorbonne Universités (UPMC/CNRS/IRD/MNHN), Paris, France
  • 3Institute of Coastal Systems Analysis and Modeling, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
  • 4Institute of Oceanography, Center for Earth System Research and Sustainability, Universität Hamburg, Hamburg, Germany
  • 5Deutscher Wetterdienst, Hamburg, Germany
  • 6Max Planck Institute for Meteorology, Hamburg, Germany

The North Atlantic Oscillation (NAO) has over the year a major influence on European weather. In many applications, being it in modern or paleo climate science, the NAO is assumed to varying in strength, but otherwise often understood as being a constant feature of the pressure system over the North Atlantic. In recent years investigations on the seasonal-predictability of the winter NAO has shown that the prediction skill is varying over time. This opens the question, why this is the case and how well models are able to represent the NAO in all its variability over the 20th century.

To investigate this further we take a look at a seasonal prediction of the NAO with the Max Planck Institute Earth System Model (MPI-ESM) seasonal prediction system, with 30 members over the 20th century. We analyse its dependence of prediction skill on various features of the NAO and the North Atlantic system, like the Atlantic Multidecadal Variability (AMV). As such we will demonstrate, that the NAO is a much less stable system over time as currently assumed and that models may not be in the position to predict its full variability appropriately.

How to cite: Düsterhus, A., Borchert, L., Koul, V., Pohlmann, H., and Brune, S.: Variability of the North Atlantic Oscillation in the 20th century, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12580, https://doi.org/10.5194/egusphere-egu21-12580, 2021.

Display materials

Display file

Comments on the display material

to access the discussion