Canada is a big country, with a lot of forest and a lot of water. Fires are common, and are concentrated in the boreal forest region, a band of forest that stretches around the whole northern hemisphere. On average, out of around 400 million ha of forest, about 8,000 fires and 2.5 million ha burn per year. And dozens of communities and tens of thousands of people need to be evacuated each year.
People are mostly concentrated along the southern border with the United States, where it’s warmer. A lot of the northern communities are actually indigenous, and many of them are only accessible by air or water. If there is a road, it’s the only road. These communities are often threatened by wildfires, and are frequently evacuated due to this threat.
Ultimately, Canada has three main problems with respect to wildland fire - prevention, detection, and suppression. The Canadian Forest Fire Danger Rating System (CFFDRS) helps with each, though it’s only part of the solution. It helps with prevention by allowing fire managers to know where the risk of fires is higher. It helps with detection by giving fire managers a place and time to look for new fires. And it helps with suppression by providing some guidance about how the fire will behave. Beyond fire prevention, detection and suppression, CFFDRS helps with planning, response, risk assessment, smoke modelling, and even carbon emissions from these fires.
With respect to wildland fire, the Government of Canada has a mandate to provide for the safety and security of Canadians, to protect critical infrastructure, to mitigate the effects of climate change, and to aid the implementation of other Sustainable Development Goals like reducing poverty and improving health. All are aided by the CFFDRS.
Focused research on the development of the CFFDRS began in 1968, but built on a lot of previous work. And development is ongoing.
The major components of the CFFDRS are the Fire Weather Index (FWI), the Fire Behaviour Prediction system (FBP), and the Fire Occurrence Prediction system (FOP). The FWI is an accounting system for moisture that uses temperature, relative humidity, wind speed, and precipitation, each taken once a day at noon. For most jurisdictions around the world, the FWI is the most important component and is analogous for fire danger rating. The system is designed to derive the maximum amount of information from the least amount of data and for this reason is easily adapted to regions outside of Canada. However, before it can be used it needs to be calibrated. Calibration means analyzing FWI output and comparing to actual fires and fire behaviour to gain a proper appreciation of what the numbers really mean.
If fuels data is added to the system, it is possible to predict fire behaviour. Fire behaviour prediction (FBP) is how the relative indices of the FWI are converted into real units such as rate of spread (how fast the fire can grow, in metres per minute), head fire intensity (how big the flames are, basically, in kW/m), and fuel consumption (how much biomass is consumed by the fire, in kg/m2).
So, what evidence is there that the CFFDRS (or any danger rating system) is effective? In Canada, it has helped to provide for the safety and security of people, reducing deaths and injuries from wildfire. It is used to pre-deploy firefighting resources. Certainly there is a high correspondence between areas of high fire danger and actual fire activity.
Finally, after seeing the great work being done in India by the Forest Survey of India, the North Eastern Space Application Centre, and the National Remote Sensing Centre, I think that the next step is to decide who the audience is for their products. There may be several audiences, each with different needs and capabilities. This will help to determine where they go from here.
Read other blogs from this workshop here.