wildfire - cause and distribution Flashcards
what are wildfires?
uncontrolled fires that destroy most things in their paths
what are the three types of wildfires?
ground fire
surface fire
crown fire
what is a ground fire?
where the ground itself is alight such as peat and small roots
slow with no aflame just smoke
what is a sirface fire?
where leaf litter and low vegetation burn
intensity can vary
what is a cronw fire?
where the fire moves rapidly through the canape
intense and fast moving
for a wildfire to start and spread what two things are neded?
an ignition source and fuel
what can be an ignition source?
lighters matches cigarettes power lines lightening
what two natural things can cause wildfires?
lightening
volcanic eruptions
what are the categories of conditions that determine a wildfire?
vegetation type
fuel characteristics
climate and recent weather
fire behaviour
what vegetation type do wildfires favour?
thick undergrowth or closely spaced trees allowing it to travel
oily plants such as pine
what fuel characteristics favour wildfires?
fine, dry material such as twigs and dry grass
fuel that forms a continuous cover
what climate do wildfires favour?
areas with a distinct dry season but enough rainfall for vegetation to grow
strong winds provide oxygen but also spread the fire
what is a creeping fire?
moves across the ground surface very slowly
what is a running fire?
spreads rapidly and intensely
what are examples of regions that experience wildfires?
canada
usa
parts of australia
southern europe such as italy
