Fires in Nature Flashcards
What are wild fires?
Large uncontrolled destructive fires that burn quickly over grassland and woodland
What are the 3 types of wild fires?
- ground fires
- surface fire
- crown fire
Ground fire
Fire that occurs on the ground e.g. peat, tree roots
Surface fire
leaf litter and low lying vegetation burn
Crown fire
fire moves rapidly through the canopy; fires are more intense and fast-moving.
Distribution - class notes
- Predominantly occurs in outskirts of Australia, in areas prone to the risk of drought.
- Mid/Southern/Western Africa
- North Africa = low levels of wildfires
- High levels of wildfires in northern areas of South America + Southern areas of Northern area
Distribution - Snaprevise notes
USA
- West experiences SERIOUS droughts = serious wildfires
- California, Utah, San Francisco
- Rural hazard - not urban - expanded human habitation in rural areas/ plants that would usually be in rural areas are also in urban areas.
what are the conditions needed 4 wildfires?
- vegetation types
- Fuel characteristics
- climate and recent weather
- fire behaviour
Vegetation types
- thick undergrowth
- ## trees containing a lot of oil e.g. pine, eucalyptus = burns much more quickly (enables the fire to move much quickly
Fuel characteristics
- fine dry material
- e.g. things that catch fire and burn easily e.g. a twig
- large amounts of fuel that form continuous cover will help the fire burn for longer and spread faster
Climate and recent weather
- rainfall must be sufficient for vegetation growth
- fires happen usually in places with dry seasons with no rain and high temperature for a long time: allows vegetation to dry out.
Fire behaviour
- Creeping fires move across grounds fairly slowly
- running fires spread rapidly and are more intense
- fires throw out burning debris
this spreads fire and CaUseS it to become more InTeNSE.
HUMAN CAUSES aka SACMBF
- Sparks from machinery
- Arson
- Cigarettes
- Managed fires
- Barbecues
- Fireworks
Natural causes
Lightning
Volcanic eruptions
Distribution - natural ecosystems
what else is included?
natural ecosystems
Phyrophytic
Rainforests
LA California
Natural ecosystems - which areas are wildfires most beneficial to?
- Mediterranean
- savannah - grassland - Africa
why are wildfires beneficial to areas mentioned in natural ecosystem flashcard?
aids new seed germination
kills pesticides/parasites
stimulates new growth of plants
state a material that is naturally resistant to wildfires
Pyrophytic
a type of tree
its bark is fire resistant which protects it
e.g. Baobab
why are rainforests still at risk of fires?
because of human activity
despite the rainforest being wet - a natural deterrent t wildfires
H (however) humans still set it on fire to clear space for agricultural farming (like palm oil) or for intensive animal farming
+ micro-farming
Tell me a bit about Los Angeles, California
- drought resistant shrubs (in the city - susceptible to fire)
- winds - Santa Ana winds
- low building density outside city - the fires within urban areas - at HUGe risk
EFFECTSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS
- loss of crops - timber x livestock
- loss of life
- loss of property - houses x buildings
- release of toxic gases + particulates
- loss of wildlife - poor koala bears :-(
Secondary Effectsss
Evacuation - loss of land + possession particularly in dry urban areas
increased flood risk - plants and trees act as interception to water - instead of going towards fire it flows towards river and creates flash floods
ManaGEmenT
managing vegetation
- shrubs removed/cleared away to subsequently avoid spreading of fire
Managing built environment
- avoid planning buildings in areas of high risk and avoid places of no human contact so that the hazard risk is not that deep.
Modelling
- route of fire
so map the route of the fire to track it
Insurance
Education
- people need to know whether they are in the area of risk or not so that they can go and get some insurance
+ prevent careless actions that ignite these risks
Dealing with the fire
Fighting the fire - volunteer firefighters - like fireman SAM Spraying water/ chemical - now this is \$\$$ so its not the most favourable option but is quite effective Ground - bulldoze breaks to clear vegetation - beat out fires Retardants - where life or property is threatened by fire - spraying in inaccessible areas via air
Summary
- first test yourself to see how much you remember
- then look at answers, write down and repeat saying out loud several times and then try to recall it from memory after covering info up
Natural events: lightning, but can be caused by humans too
Nature of fires + climate, type of vegetation + strength of wind
Fire = ignition services
Fire = rural hazards - expand into these areas + urban if they have dry vegetation prone to fire risk
Benefits
- list regions
- seed germination
Effects: loss of crops, livestock, property, wildlife, damage to soil - increased flood risk + evacuation required to areas of risk
Prevention x Protection
- managing environment
- provide education
- efficient warning systems
