Raman water vapour concentration measurements for reduction of false alarms in forest fire detection

Abstract

Forest fires can be the cause of environmental catastrophe, with the natural outcomes of serious ecological and economic damages, together with the possibility to endanger human safety. At the aim to reduce this catastrophe several author have been shown that the Laser light scattering can be uses to reveals the particulate emitted in the smoke. Infact experimental and theoretical investigations have shown that lidar is a powerful tool to detect the tenuous smoke plumes produced by forest fires at an early stage. In early 90's Arbolino and Andreucci have shown the theoretical possibility to detect the particulate emitted in atmosphere from smoke forest fire. Vilar at all have shown experimentally the possibility to measure the density variation in atmosphere due to plume emitted in forest fire event. Gaudio at all. have already shown that it is possible to evaluate water vapor emitted in smoke of vegetable fuel using a CO₂ dial system. In this paper a theoretical model to evaluate the capabilities of a lidar system in fire surveillance of wooded areas will be presented. In particular we intend propose a technique to minimizing the false alarm in the detection of forest fire by lidar based on a measurement of second components emitted in a combustion process. Usually to detect a fire alarm a rapid increase of aerosol amount is measured. If the backscattering signal report a peak, the presences of a forest fire will be probable. Our idea to confirm this hypothesis is measure the second components emitted in a forest fire at the aim to minimize the false alarm. The simulated measurements of the humidity amount within the smoke plume will be carried out by means of Raman analysis. Fixing the burning rate of the vegetable-fuels, the maximum range of detection will be evaluated.