Figure 8. Comparison of model predictions and German 
aircraft data 
Additionally, Fig. 8 compares the predicted particle 
clouds and drift paths generated by Level-1 and Level-II 
processing. The shift in the drift paths results mainly 
from the different centre coordinates delivered by 
EMSA and REviSED due to the different algorithms 
used. The red star shows the centre of mass of the 
particle cloud calculated by the REviSED algorithm, 
whereas the orange star represents the center of a 
bounding box enclosing the EMSA sliapefile. Though 
the predicted Level-II particle cloud and the aircraft 
observation do not overlap, the predicted distribution for 
Level-II processing at the aircraft overflight time 
reproduces the shape of the pollution actually observed 
by the aircraft much better than the Level-1 model result. 
During the remaining time of the project, the available 
set of similar pairs of remote sensing observations will 
be analysed systematically for validation purposes. 
7. SUMMARY AND OUTLOOK 
Using the developed methods and tools for combining 
the near-real time remote sensing data with the drift 
model, the model input and the predicted particle 
distributions are significantly improved and the 
procedures become to a higher degree automatic. 
Further, the drift output is earlier available as a source 
of information for the operational oil spill combat. In 
addition, the remote sensing data can serve as validation 
data for the drift model and thus provide valuable 
feedback for the further development and for the 
assessment of the model. Additionally, the results of this 
subproject will contribute to the further development of 
SeaTrack Web [16] which is the official HELCOM drift 
forecasting system commonly developed by SMHI 
(Swedish Meteorological and Hydrological Institute), 
DaMSA (Danish Maritime Safety Administration) and 
BSH.