Prediction of the daily number of forest fires

On the basis of a qualitative index ( D aily F ire R isk) for the meteorological severity, a model for predicting the daily number of forest fires over a zone is developed. DFR is obtained for each day from (e, D) values, where e is the parameter of stability in the lowest atmospheric layer (850–700 hPa) and D is the saturation deficit at lowest level (850 hPa). Both e and D are evaluated at 00.00 UTC from radwindsonde data. Four types of day may be described: I, II, III and IV-type if a classification on (e, D) values is established. Very High fire activity is associated with type-I days; High with Type-III; Low with type IV and Very Low with type-II days. As in the case of other qualitative indices, two days which present an identical index may register a very different number of forest fires. This is due to the fact that the fire activity on a day d does not depend exclusively upon meteorological parameters of the day d . A second question to consider is related to the prediction of the daily number of fires PNF(d) . In this way, an initial hypothesis may be PNF(d) = PW(d) W(d) , in which PW(d) and W(d) are the Past Weather and the (present) Weather for each day d . If several considerations such as PW(d) ≈ PW(d–1) are introduced, a working expression for the daily number of forest fires results. The results obtained confirm the utility of the model and, consequently, it should be used to establish correct antifire management. Keywords: Forest fires, Fire weather, Meteorology and forest fires. International Journal of Wildland Fire 9(3) 207 - 211 Full text doi:10.1071/WF00003 © CSIRO 1999