Module 8 airborne scanner applications

A development project to evaluate the use of airborne scanner applications (casi^TM and LIDAR) as a rapid and cost effective means of surveying habitats and landscape features.

We are grateful to the Environment Agency for supplying the casi^TM and LIDAR data used in this CS2000 module. The Environment Agency holds the copyright on these data.

• Click here to access the final report for this module

This project is evaluating the use of airborne remote sensing in Countryside Survey 2000. Scanners, such as the Compact Airborne Spectrographic Imager (casi^TM) and LIght Detection And Ranging instrument (LIDAR) have considerable potential for environmental monitoring over an extent and at a scale which is intermediate between the field survey and the satellite census. The casi^TM instrument 'sees' in the visible and near infrared spectrum, whilst LIDAR uses a laser beam to measure distances. More information about casi^TM and LIDAR is available here.

Three dimensional image created by overlaying casi^TM data onto LIDAR data.

• Evaluate the use of airborne scanning (casi^TM, LIDAR) to measure the extent and identify the spatial patterns of land cover, linear landscape features and widespread habitats in example survey squares;

• Derive accurate height information, using LIDAR, which would allow definition of slope, run-off patterns, identification and measurement of individual trees, hedgerows and ditches and help in the textural identification of areas of semi-natural vegetation.

• Assess the extent to which casi^TM and LIDAR information can be used to supplement the CS2000 field survey for the landscapes surrounding the example squares so that patterns observed within the squares can be placed in their wider landscape context;

• Compare the casi^TM and LIDAR imagery with the satellite data and resulting products, to assess the value that the higher resolution can contribute to synoptic surveys of the countryside.

• Assess the feasibility and accuracy of detecting landscape change using casi^TM and LIDAR information and assess how the airborne sensors may be used in conjunction with field survey and satellite remote sensing in future re-surveys.

• Evaluate the accuracy of methods and above products in the survey of independent examples of squares (for which ground reference data are unseen).

Examples of CS2000 squares have been overflown and scanned using the casi^TM and LIDAR sensors. A trial study of four 1 km squares has allowed us to experiment with procedures, refine methods, validate products and plan a sampling strategy. We will subsequently assess procedures in 'blind trials' of a further four 'check' squares, comparing results with the independent field reference data of CS2000 to demonstrate the potential for operational use.