KLIWAS 
Seite 30 
KLIWAS 
Climatology 
of North Sea 
Fronts 
Despite all restrictions discussed above, the preliminary products show clearly an 
impact of the wind field on front position and gradient strength. However, the results 
a basing on a large-scale wind field covering the whole North Sea which is not 
always representative for the German Bight or other selected area (see all the 
different meteorological forecast areas of European met services in the North Sea). 
Much more precise and significant results can be expected if the real local wind field 
(e.g. as recorded by station data) or hind-cast data are used for this analysis. Of 
course, this can’t be done fully automatically, but should be added in a later project 
period for selected North Sea regions as an appendix for this climatology. First 
studies in the framework of KLIWAS have shown also, that frequency and local 
pattern of prevailing wind directions is expected to change over the North Sea in 
future decades (Gaslikova et al., 2012, Ganske and Rosenhagen, 2013). They suggest 
an increase of westerly directions and a decrease of northerly and easterly winds (Fig. 
13) which will inevitable change the location and intensity of oceanic fronts. 
Fig. 13: Sign and significance of trends of yearly wind direction frequencies between 1961 and 
2099 calculated with 5 different RCM runs for 5 North Sea subareas. Each segment of a circle 
shows the results for the corresponding wind direction class. Each circle contains the results of a 
specific RCM, where positive significant trends are shown in pink, negative significant trends in 
blue and non-significant trends in white. Shown are results from the runs of: IPSLCM/REMO, 
ECHAM5_l/REMO, MPI-OM/ECHAM5_3/REMO, ECHAM5_3/RACMO and 
ECHAM5_3/HIRHAM5 (from inner to outer circle). The figure shows the result for all wind 
speeds. By courtesy of A. Ganske.