The Absorbing Aerosol Height (AAH) is a new GOME-2 product for aerosol detection developed within the Atmospheric Composition Satellite Application Facility (ACSAF). It uses the Absorbing Aerosol Index (AAI) and derives the actual height of the absorbing aerosol layer in the O2-A band using the Fast Retrieval Scheme for Cloud Observables (FRESCO) algorithm (Tilstra et al. 2010). This AAH product could be used to monitor volcanic eruptions globally and to provide the height of the ash layers (e.g. within the framework of aviation safety). To determine the quality of the AAH, a new quantitative validation exercise has been done, using the extracted height of the different aerosol layers from CALIOP and comparing this to the AAH from GOME-2. The results from different case studies will be presented.