U. Callies et al.: Surface drifters in the inner German Bight 
825 
www.ocean-sci.net/13/799/2017/ 
Ocean Sei., 13, 799-827, 2017 
The Supplement related to this article is available online 
at https://doi.org/10.5194/os-13-799-2017-supplement. 
Author contributions. JH collected the field data. SM provided 
BSHcmod currents and her experience regarding performance of 
the operational model. HaK produced the TRIM simulations. FS 
preprocessed the raw drifter data for comparison with model data. 
HoK produced the residual current classification based on BSHc 
mod surface currents. NG conducted the WAM simulations. UC 
prepared the paper with contributions from all co-authors. 
Competing interests. The authors declare that they have no conflict 
of interest. 
Acknowledgements. This work was kindly supported through 
the Coastal Observing System for Northern and Arctic Seas 
(COSYNA). Wind observations at the Heligoland station were 
provided by the Deutscher Wetterdienst (DWD). Graphs were 
produced using the Generic Mapping Tools software (GMT) 
available from www.soest.hawaii.edu/gmt/. We appreciate valuable 
comments by Joakim Kjellsson and two anonymous reviewers that 
helped improve the presentation of our results. 
The article processing charges for this open-access 
publication were covered by a Research 
Centre of the Helmholtz Association. 
Edited by: Andreas Sterl 
Reviewed by: Joakim Kjellsson and two anonymous referees 
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