Prospective sensors for space-borne fire observation

Kurzfassung

Remote sensing is one of the requisites for assessing the wildfire risk, documenting the spatio-temporal distribution of active fires, and monitoring the impacts of bio-mass burning in order to assess climate change, and to support the surveillance of international conventions. Space-borne remote sensing has not yet provided the performance necessary to detect active fires for fire suppression, but there is great interest in such a capability. Existing space-borne sensors are able to provide information on fire risk, as well as to monitor burned areas. The use of existing space-borne sensors for active fire recognition suffers from serious limitations, such as saturation effects in the mid-infrared channel, and inadequately ling revisit times. They present snapshots of fire occurrences only. Active fire counts derived from existing sensors may be overestimated due to a confusion with hot surfaces and sun glint from reflective surfaces, such as water and clouds, or underestimated due to coarse spatial resolution. The global change research and disaster management communities expect quantitative information on fire characteristics from new and dedicated space-borne fire observation sensors. The Moderate Resolution Imaging Spectroradiometer was launched in December 1999 on EOS Terra and will deliver quantitative parameters of wildfires on a global scale, but with 1-1.5 km ground resolution only. The planned US National Polar-orbiting Operational Environmental Satellite System Preparatory Project aims to provide continuation of global observations following the EOS Terra and EOS Aqua missions. The German Aerospace Center (DLR) and its industrial partner OHB-System, have been working on two new space-borne fire missions since 1994: the DLR small satellite mission BIRD (Bi-spectral IR Detection), and the intelligent infrared sensor system FOCUS to be flown as an early external payload of the International Space Station. Furthermore, a consortium of European space industries and German Aerospace Center led by INSA are currently designing and developing payload prototypes of a Forest Fire Earth Watch mission. A comparison of the active fire recognition capabilities of these prospective sensors with existing and planned meteorological sensors is provided in this chapter.