A Crop Information System Incorporating ERS SAR Data: Applications in the UK and Paraguay

Abstract

The capability of satellite radar to acquire images independently of cloud coverage or daylight conditions is of major significance in the context of agricultural applications, which are time critical. The accurate identification of crop types depends on the availability of images acquired within specific time windows through the growing season when there are marked differences in the appearance of particular crop types on remote sensing images. Despite the progress which has been made towards operational applications, experience shows that high resolution optical satellite sensors cannot always provide the desired information due to constraints related to cloud cover and revisit schedules.

This paper describes the analysis techniques which have been developed to extract agricultural information from ERS images. These focus on field-based extraction of image statistics (parcel means) and crop classification using a Remote Sensing Crop Information System (CROPINS) with special capabilities for integrated handling of optical and radar data.

Results of synergistic use of optical and microwave satellite data for crop classification using temporal spectral signatures will be presented for test sites within the UK and Paraguay. In the UK, the work focuses on two MARS Activity B sites, Driffield and King's Lynn, which show differences in topography, soils, cropping and management practices. In Paraguay information is required on 4 major crops - soya, wheat, cotton and maize. Approximately 80% of the national soya and wheat crops are grown in the departmentos of Alto Paraná and Itapuá and for this reason analysis has concentrated on these areas.

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, atmospheric chemistry