On the Application of Nighttime Sensors for Rapid Detection of Areas Impacted by Disasters

Today a few sensors operating at night are available in the visible/near infrared part of the spectrum, e.g., the U.S. Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS). However, in the case of DMSP/OLS, the availability of a series of satellites arranged in a constellation and the width of the sensor’s swath allows Earth coverage twice nightly. This can result useful in the aftermath of a natural disaster such as earthquake, when first responders providing relief action need to know the location and the extent of the areas of damages, the potential amount of population involved and the place where survivors are concentrated. Naturally, after this prompt detection of the areas affected by the event, the corresponding very high spatial resolution satellite images can be acquired to obtain an accurate overview of the actual damages. In fact, the availability of a preliminary fast estimate of the areas mainly impacted can support a suitable selection of the very high spatial resolution (VHSR) satellite images acquisition time because these sensors are characterized by a very small frame size that makes unpractical a blind acquisition of the whole region possibly impacted. This way to proceed is also compatible with the longer time usually needed to obtain a VHSR image of a given area of interest, due to the orbital and observation geometry constraints.