Topographic data is crucial to the building of structures, disaster damage forecasting and more. The use of satellite data has afforded much more precise information.
Wide ranging and precise height data
The PRISM optical sensor onboard the ALOS excels at collecting accurate height data (Digital Surface Model:DSM) over a wide area. You might even say that this is what PRISM was designed for.
PRISM collects images from three directions at once, and heights can be determined from the stereo parallax among the images. It is possible to collect height data from images from two directions, but having three different angles boosts precision. And the only satellite covering the entire globe to obtain height data at this resolution and precision with this exclusive configuration is ALOS.
Topographic data based on the high resolution/precise height data is used for cartography and in other fields. Topography is the basis for understanding the flow of water, meaning it has a role in dam building and flood damage forecasting, for example. Highly accurate topographical data is also essential to the placement of electricity pylons for power transmission.
Highly accurate pan-sharpened images can be generated by PRISM and AVNIR-2
PRISM and AVNIR-2 are recording at the same time, so there is no difference in vegetation on account of time lapse. This creates a unique capability for highly accurate pan-sharpened images.
Images can be obtained from the satellites that have a resolution of 2.5 m (provided by PRISM) and are in color (from AVNIR-2).
It also allows for the creation of vivid bird’s eye view images by using the DSM from PRISM, as seen in the graphic above.