GMES Fast Track Land Service 2006-2008 - Orthorectification of SPOT 4/5 and IRS-P6 LISS III Data

Abstract

The GMES (Global Monitoring for Environment and Security) Fast Track Land monitoring Service (FTLS) is a service to provide on a regular basis land cover and land use change datasets, which can be used by a wide range of downstream services at European, national, regional and local scale. Under ESA contract DLR (German Aerospace Center) produced two multi-temporal datasets of orthorectified images covering the participating EU27 and neighbouring countries (overall 38 countries). An operational and automatic processing chain to process about 3700 satellite images has been established including quality control and creation of a European wide consistent GCP database. The orthorectified products are derived from a mixture of high resolution satellite images from SPOT 4 with 20 m GSD, SPOT 5 with 10 m GSD and IRS-P6 LISS III with 23 m GSD, each with four spectral bands, and geometrically corrected towards European Map Projection with 25 m resolution and national map projection for each country with 20 m resolution using DLR’s in-house developed versatile orthorectification S/W package. An overall geometric accuracy of about 10 m RMSE in each direction with respect to the European land cover dataset Image2000 (EU25) and USGS ETM+ land cover dataset (neighbouring countries) has been reached. The paper describes the background of the Image2006 project, the newly developed procedures and methodologies of the automatic and operational orthorectification chain including its limitations in problematic cases, as well as the results in terms of statistical evaluations.