Journal cover Journal topic
Earth System Dynamics An interactive open-access journal of the European Geosciences Union

Journal metrics

  • IF value: 3.635 IF 3.635
  • IF 5-year<br/> value: 3.869 IF 5-year
  • CiteScore<br/> value: 4.15 CiteScore
  • SNIP value: 0.995 SNIP 0.995
  • SJR value: 2.742 SJR 2.742
  • IPP value: 3.679 IPP 3.679
  • h5-index value: 21 h5-index 21
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
13 Apr 2017
Review status
A revision of this discussion paper was accepted for the journal Earth System Dynamics (ESD) and is expected to appear here in due course.
Low frequency variability in North Sea and Baltic Sea identified through simulations with the 3-d coupled physical-biogeochemical model ECOSMO
Ute Daewel1 and Corinna Schrum1,2 1Helmholtz Centre Geesthacht, Institute of Coastal Research, Max-Planck-Str. 1, 21502 Geesthacht, Germany
2Geophysical Institute, University of Bergen and Hjort Centre for Marine Ecosystem Dynamics, Allegaten 41, 5007 Bergen, Norway
Abstract. Here we present results from a long-term model simulation of the 3d coupled ecosystem model ECOSMO II for a North and Baltic Sea setup. The model allows both multi-decadal hindcast simulation of the marine system and specific process studies under controlled environmental conditions. Model results have been analysed with respect to long-term multi decadal variability in both physical and biological parameters with the help of empirical orthogonal function (EOF) analysis. The analysis of a 61-year (1948–2008) long hind cast reveals a quasi-decadal variation on salinity, temperature and current fields in the North Sea in addition to singular events of major changes during restricted time frames. These changes in hydrodynamic variables where found to be associated to changes in ecosystem productivity that are temporally aligned with the timing of reported regime shifts in the areas. Our results clearly indicate that for analysing ecosystem productivity spatially explicit methods are indispensable. Especially in the North Sea a correlation analysis between atmospheric forcing and primary production (PP) reveals significant correlations for NAO and wind forcing for the central part of the region, while AMO and air temperature are correlated to long-term changes in the southern North Sea frontal areas. Since correlations cannot serve to identify causal relationship we performed scenario model runs with perturbing the temporal variability in forcing condition emphasizing specifically the role of solar radiation, wind and eutrophication. The results revealed that, although all parameters are relevant for the magnitude of PP in the North Sea and Baltic Sea, the dominant impact on long-term variability and major shifts in ecosystem productivity was introduced by modulations of the wind fields.

Citation: Daewel, U. and Schrum, C.: Low frequency variability in North Sea and Baltic Sea identified through simulations with the 3-d coupled physical-biogeochemical model ECOSMO, Earth Syst. Dynam. Discuss.,, in review, 2017.
Ute Daewel and Corinna Schrum
Ute Daewel and Corinna Schrum


Total article views: 447 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
362 62 23 447 1 21

Views and downloads (calculated since 13 Apr 2017)

Cumulative views and downloads (calculated since 13 Apr 2017)

Viewed (geographical distribution)

Total article views: 447 (including HTML, PDF, and XML)

Thereof 447 with geography defined and 0 with unknown origin.

Country # Views %
  • 1



Latest update: 16 Aug 2017
Publications Copernicus