Background

The Japanese Advanced Land-Observing Satelite (ALOS) was launched 24th January 2006 and made significant contributions to the fields of mapping, precise regional land coverage observation, disaster monitoring, and resource surveying before suffering a power failure on 21st April 2011.  A follow-on mission ALOS-2 is currently being prepared for launch.

The methods and computer codes made available under "contents" were developed during a project at Sheffield between 2009-2011 and used to analyse Synthetic Aperture Radar (SAR) data from the ALOS PALSAR. There is no guarantee implied that we have found the best or most efficient methods but we make them available in the hope that they can be used as a basis for further development. Please acknowledge our work if you find them useful.

Measuring Tropical Deforestation with ALOS

A key advantage of microwave Synthetic Aperture Radar over optical based systems such as Landsat and MODIS is the ability to "see through" clouds. Cloud cover is especially problematic in tropical regions where deforestation operations are also frequently difficult to police. Our particular interest at Sheffield was in detecting deforestation events using ALOS imagery with the aim of developing a monitoring scheme to complement such existing optical-based systems. The purpose of this site is to describe and make available methods and codes that were developed as part of a project that ran between Aug 2009 and Aug 2011 with the aim of developing methods to detect deforestation in the tropics using ALOS SAR. The key issue is to identify backscatter changes in tropical forest associated with deforestation. More detail about the objectives is given here and a summary of results is given here and in this poster.

The key findings of that project are fully described in a paper:

  1. Whittle, M., Quegan, S., Uryu, Y., Steüwe, M. Yulianto, K.
    Detection of tropical deforestation using ALOS-PALSAR: A Sumatran Case Study.   Remote Sensing of Environment 124, (2012), 83-98.
    2. Link to abstract (.pdf).     Link to manuscript (.pdf).

    and some extensions to the method discussed in the following unpublished manuscript:

  2. Whittle, M., and Quegan, S.
    Texture-enhanced detection of tropical deforestation using ALOS-PALSAR.  
    3. Link to abstract (.pdf).     Link to manuscript (.pdf).