The fastest bushfire ever recorded in Australia, and indeed one of the fastest in the world, was the 2003 Canberra bushfires. These fires exhibited extreme behavior, with fire fronts moving at speeds of up to 12.6 kilometers per hour (7.8 miles per hour).
The fastest grass fire ever recorded in Australia was during the Black Saturday bushfires on February 7, 2009. During this catastrophic event, the fire front moved at an exceptional speed, estimated to be over 120 kilometers per hour (75 miles per hour) in some instances.
Slope Gradient (%) | Slope Angle (Degrees) | Relative Rate of Spread |
---|---|---|
0 | 0 | 1x |
20 | 11 | 2x |
45 | 24 | 4x |
70 | 35 | 8x |
100 | 45 | 16x |
Initial Fire Speed (km/h) | Slope Degree (Degrees) | Resulting Fire Speed (km/h) |
---|---|---|
5 | 0 | 5 |
5 | 10 (uphill) | 10 |
5 | 20 (uphill) | 20 |
5 | -10 (downhill) | 2.5 |
5 | -20 (downhill) | 1.25 |
understanding the impact of slope on fire behavior is critical for predicting and managing wildfires. The role of slope must be considered along with other environmental and weather factors to accurately assess and respond to wildfire risks.
The effects of slope on fire behavior are a crucial aspect of wildfire management and understanding. The primary mechanism through which slope impacts fire behavior is through the preheating of fuels uphill from the fire. As a fire burns, it radiates heat upwards, which preheats the fuel above it on a slope. This makes the fuel more combustible, and as a result, fires tend to move faster uphill.