Using ENVISAT MERIS data to detect oceanic coccolithophore blooms in the North Atlantic
(1) Freie Universitaet Berlin, Carl-Heinrich-Becker-Weg 6-10, 12165, Berlin, Germany
MERIS reduced and full resolution data are operationally used for the retrieval of in-water constituent concentrations in open oceans and coastal waters. As included in the MERIS standard level 2 product or e.g. the FUB Case-2 Beam/Visat Plug-In concentrations of pigments, particulate suspended matter and yellow substance absorption are routinely derived.
Due to the band setting, the spectral and geometrical resolution MERIS data can be used to detect aquatic phytoplankton blooms that uniquely influence the water-leaving signal. E.g. blooms of oceanic coccolithophores alter water-leaving radiances because of their (a) species assemblage with (b) distinctive inherent optical properties, (c) high concentration ranges, and (d) the vertical distribution within the water column.
We present an algorithmn that allows the detection of oceanic coccolithophore blooms and the retrieval of its calcite concentration. The processing is based on radiative transfer forward simulations and artificial neural network inversion. The sensitivity of water-leaving - and considering atmospheric influences - top-of-atmosphere signals are studied.
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,