MERIS Products - getting, understanding and using them for open ocean and coastal zone applications

Carsten Brockmann
Brockmann Consult, 21502 Geesthacht, Germany
carsten.brockmann@brockmann-consult.de

ABSTRACT

The Medium Resolution Imaging Spectrometer, MERIS, onboard the ESA ENVISAT satellite is the most suitable instrument in space today for coastal zone and open ocean applications. The instrument has been in operation for 3 years now and after an initial period of calibration, validation and product improvement, the exploitation of this data is increasing. The still comparably limited use of MERIS data is, to a certain extent, due to the uncertainty concerning product access and product definition.

The different ways in which one can obtain MERIS data will be described presently. This includes the rolling archive, the telecommunication satellite link (DDS), the distribution on media, and the online access to the reprocessed data of 2003 and to the diagnostic ocean data sets. The differences in the production and distribution of Reduced and Full Resolution data will also be explained.

A Level 2 product includes 30 geophysical parameters and 30 flags. Among these, 18 geophysical parameters and 19 flags are relevant for coastal and ocean applications. The scientific definition of each parameter and flag is described in an Algorithm Theoretical Basis Document. These are currently being updated, and an up-to-date description of the algorithms of the most important parameters, such as the algal1, algal2, total suspended matter and the atmospheric correction, are presented here.

The full power of MERIS Level 2 products lies in the combined interpretation of the atmospheric and marine parameters with the relevant scientific flags. This is specifically important for oceanic and coastal applications. The aerosol parameters, the water vapour, the wind speed, pressure and the related flags describe the state of the atmosphere. The surface reflectance spectra and related flags indicate the quality of the atmospheric correction. The marine parameters and flags describe the state of the water body. Examples of the combined interpretation of these parameters will be presented.

Last Update: 2005-04-5