Introduction - ASAR

ENVISAT consists of ten radar and optical instruments providing continuous observation of the Earth since its launch in 2002.

ENVISAT is the largest earth observation spacecraft ever built providing information about land cover, the oceans, ice caps and the atmosphere.
The Advanced Synthetic Aperture Radar (ASAR) is an active sensor providing land cover data in the day or night.

Alternating Polarisation - ideal for local studies focusing on applications such as vegetation type and land cover mapping.
Image Mode - can combine more than one image to create a multi-difference colour composite which aids change detection at a local/regional scale.
Wide Swath - usually used to assess large areas of land, this data should be used for regional studies such as soil moisture monitoring, flood assessment, coastal protection and surface deformation.