Coastal Processing Requirements and Techniques
Carsten Brockmann(1) and Kerstin Stelzer(1)
(1) Brockmann Consult, Max-Planck-Str. 2, 21502 Geesthacht, Germany
The importance of coastal waters for ecology and economy has been stressed since the mid 1980s. MERIS has been designed specifically to deliver water constituents in the coastal zone: the band setting with band 1 at 412nm for yellow substance absorption, band 7 at 665nm for pigments and suspended sediment, band 8 at 681nm for chlorophyll fluorescence and 4 bands in the NIR for the atmospheric correction over turbid waters as well as the spatial resolution of 300m are optimised for coastal applications.
In the context of the Water Framework Directive the most important part of the coastal zone is the narrow stripe of 1 nautical mile off the baseline. This very near coastal area is specifically critical for processing of satellite data. The following problems need to be addressed for the retrieval of water constituents in such coastal waters: (1) geolocation accuracy (important for Level 3 processing), (2) atmospheric correction over turbid waters, (3) non maritime aerosols, (4) adjacency effect, (5) submerged vegetation, (6) bottom reflection, (7) mixed land/water pixels, (8) large range of concentrations with very high values possible, (9) algal composition.
Most of these issues have been addressed recently by studies undertaken under ESA contract (AMORGOS, Case2 Regional, Adjacency Effect correction, MERIS Quality Working Group). An overview of the results is presented here, and open issues are identified. MERIS FR and RR as well as AATSR and Chris/Proba products are used to study the effect of the different problems listed above on the spectral signature, and the improvements brought by tools made available by ESA are demonstrated.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,