This work is concerned with the use and further development of acomputer program to determine displacement vector fields fromsequential satellite images. The work was carried out as part of aGerman-Chinese joint venture between the Institute for Meteorology ofthe Free University Berlin (FU Berlin) and the Second Institute ofOceanography at Hangzhou, Peoples Republic of China.The modified computer program is based on a functional analyticapproach after Horn and Schunk (1981). From the resulting vectorfields, kinematic fields were determined using the image processingtool IDL (Interactive Data Language). In order to compute kinematicfields (e.g., vorticity and divergence), a two dimensionaldistribution of direction and velocity of the shifting grey-valuestructure was assigned to the corresponding physical quantities (e.g.,sea surface temperature) as needed. Alternatively, grey value imagesdisplaying spectral albedo can be utilized.This study tests the ability of information from the visible spectrum toyield reliable results employing data from NOAA-AVHRR (NationalOceanic and Atmospheric Administration - Advanced Very High ResolutionRadiometer). Receiving, processing (geo-correction) and archiving wasdone at the Institute for Meteorology, FU Berlin, as part of theEROS-project (European River and Ocean System) of the EuropeanUnion. Atmospheric and sunglint correction was computed to gaindisplacement vector fields using NOAA-11 data of the Black Sea, fromearly August 1993. Direct verification of displacement vector fieldswas difficult due to lack of in-situ measurements, however the resultsmay be evaluated as a useful approximation. At the times ofobservation, the displacement vector fields correlated well with thekinematic fields of the uppermost water layer.
AWI Organizations > Climate Sciences > Climate Dynamics
AWI Organizations > Climate Sciences > Sea Ice Physics