Taranaki (also known as Mount Egmont), an active
stratovolcano located on the North Island of New Zealand,
is a case in point (Fig. 1). Its eruptive history shows that it
represents a real future risk to the infrastructure that has
been built on its flanks (e.g. Palmer et al., 1991). Obviously,
risk delineation by flow modeling would be of benefit here.
However, we have shown previously that the errors in
DEMs can limit the plausibility of computer models delineating
volcanic risk, in terms of updating topographic
change and in terms of data quality (Stevens et al., 2002).
Prior to this study, the available topographic data covering
the Taranaki area were not adequately detailed for this
purpose.
The ASTER sensor on the NASA Terra satellite is a highresolution
instrument that provides a near-infrared stereo
imaging capability with a spatial resolution of 15 m, and a
swath width of 60 km (Abrams, 2000). TERRA has a 16-
day repeat interval, and ASTER has an 8% duty cycle, so a and after significant volcanic topographic and surface
change. We thus discuss the applications of the data,
including a new, efficient and low-cost methodology to
calculate potential economic loss in eastern Taranaki due
to major debris avalanching, and consider the relative merits
of ASTER DEMs versus the recently released Shuttle radar
topography mission (SRTM) topographic dataset.