MERIS-VA Software

Architecture

The MERIS value-added (MERIS-VA) processing software is the backbone of MAPP. The software is optimized for the automated processing of large data volumes. The software architecture is separated into a static engine and multiple dynamic plugins.

The engine is responsible for data transfer and processing control, while plugins encapsulate different algorithms to produce value-added data. Plugins are discerned into Level 2 and Level 3 (L2 and L3) operations. The L2 algorithms apply to individual standard Level 1 and 2 MERIS pixels, whereas L3 algorithms operate on L2-VA products to produce generic statistics (mean value, maximum-likelihood estimators), vertical cloud statistics, and land cover classification. The processing software is configurable through external XML files and can easily be adapted to specific needs.

Level 2 processor I/O		Level 3 processor I/O

Plugin modules

Various science algorithms are implemented as plugins

VA.L2.RWC_RTM	Inverse radiative transfer techniques to calculate regionalized case-II water constituents (chlorophyll-a, suspended matter, yellow substance)
VA.L2.RWC_PCI	Principal component inversion to calculate regionalized case-II water constituents
VA.L2.LCC	Monotemporal land coverage classification
VA.L2.NDVI	Normalized differential vegetation index (AVHRR compatible)
VA.L2.AER	Calculation of optical depths of coarse and fine aerosols, suspended matter content and water leaving reflectances are spin-off products
VA.L2.WV	Water vapor content
VA.L2.CLOUD	Calculation of cloud parameters (optical thickness, albedo, and top pressure)
VA.L2.SA	Calculation of surface albedo

Operation

The MERIS-VA software is integrated into the DLR Data Management and Information System (DIMS). The MERIS full-resolution data are acquired by the German receiving station in Neustrelitz and transmitted to the Envisat D-PAC in Oberpfaffenhofen where the standard ESA Level 1 and 2 MERIS products are generated. The MERIS-VA software is operated in Neustrelitz and processes input supplied by the Product Library. The MERIS-VA L2 products are continuously integrated into the MERIS-VA L3 binning database. The final L3 products are added to the Product Library.