raster change detection

[jaredmorel]

I have areal imagery from 1980, 1990, 2000, and 2009 and I am trying to map the changes in development over time.  What are your thoughts on the best and/or easiest way to do this?

Thanks for your help!

[GayathriAlallasundaram]

Hi,

If you have ArcEditor or ArcInfo, you can create multiple mosaic datasets�??one mosaic dataset for each year�??and a final master mosaic dataset to contain each of the mosaic datasets you created for each year. Then add the Year field to the mosaic dataset. You can enable time on the mosaic dataset and use the Time Slider window to navigate through the imagery in the mosaic dataset. The link below gives the worklfow on how to perform this,

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Creating_a_mosaic_dataset_containing_r...

I hope this helps.

Thank you,
Gayu

[ChrisBater]

Probably the easiest way forward is to use image differencing, where you calculate a vegetation index for each image (e.g. NDVI), difference the images (e.g. TT1-T2), then apply threhsolds to the change images to classify disturbance. A google search on change detection and image differencing might help with more specifics.