Wildfires Flashcards
What is a flashpoint?
The point at which something will burn (wood - 300C)
What is a wildfire?
An uncontrolled fire that wiped out large areas of land
What is the fire triangle?
Oxygen
Heat
Fuel
What are the 3 types of wildfires?
Surface fires
Ground fires
Crown fires
Describe surface fires
• most common
• burn along the forest floor
• burns leaf litter and fallen branches
• burn around 900
• cool quickly
• relatively easy to control
Describe ground fires
• burn organic matter in the soil (peat)
• spread slowly
• smoulder at low temperatures (540C)
• can burn for long periods of time
Describe crown fires
• burn through the canopy
• can spread through loose bark, burning whole trees
• burns at over 1100C
• most intense
• most difficult to contain
Factors affecting wildfires
Vegetation:
dry
Weather:
wind speed
Hot, dry climate
Wind direction
Humidity levels
<7% humidity = very high risk
>15% humidity = low risk
Topography:
Fires travel faster uphill
Steeper the slope = faster the fire
What are the causes of wildfires?
• lightening strike
• volcanic eruption
• sparks from rockfall
• unattended campfires
• lit cigarettes
• agricultural fires
• arson
What are the impacts of wildfires?
• disruption to ecosystems
• loss of native plant species
• loss of rainfall interception
• release of toxic gases and CO2
• destruction of soil structure
• quickly removes decaying matter from the forest floor
• germination of Douglas Fir, Sequoia and Ponderosa Pine seeds
• removal of pests
• increased sunlight to forest floor
Managing wildfires
• removal of leaf litter via controlled burning
• monitoring via satellites
• turning in lights so that properties are more visible through smoke
• evacuate homes
• distribute aid
• douse fires with water
• build protected homes
• create fire breaks
