LIDAR stands for Light Detection and Ranging.

It's a surveying technique that has many different applications and is becoming increasingly popular in archaeological landscape survey. In basic terms it allows us to see beneath most vegetation on the ground, which when manipulated in GIS software can reveal slight ungulations such as earthworks.

Watch this short video from the US National Ecological Observatory Network to see the science behind LIDAR.

The Environment Agency have just released their LIDAR data under an Open Government Licence.

The composite data covers over 72% of England. Resolutions available are 25cm, 50cm, 1m, and 2m, but coveraage appears very limited at the higher resolutions. The 1m data appears to strike a good balance of coverage and detail.

A quick and easy way to look at the 1m LIDAR data is by looking at this ready made map:

As the Environment Agency have released all their LIDAR data for free getting the data for a survey is not a problem, but manipulating it can be a different matter.

We have put together some easyish crib sheets to follow so that you can try and start working with LIDAR data for your own survey.

To start working on your own survey you will need:

• to download a free GIS software package (a link is supplied below)
• a good amount of free space on your PC (the files created can be quite large)
• need to know the Ordnance Survey reference for the area you are wanting to survey
• to download the LIDAR data (a link to data is supplied below)
• to download the Ordnance Survey data
• be organised (make sure you have seperate folders for your data, it can get confusing!)
• ...patience.

Follow the crib sheets below in order. If you have any questions you can always email the chairman.