HSC Geography · Human–Environment Interactions

# 14.1 Bushfires

Chapter 14 · Contemporary Hazard · NESA Stage 6 (2022) · Revision deck
Aboriginal and Torres Strait Islander readers are advised that this resource may contain names, images or references to people who have died.
By the end you can…

## Learning goals

- Define bushfire, natural hazard & disaster.
- Explain the fire triangle & the “big three” controls.
- Describe fire behaviour (front, embers, spot fires).
- Explain slope & climate drivers.
- Discuss fire-adapted ecosystems & cultural burning respectfully.

Section 1

# What is a bushfire?

## A uniquely Australian hazard

- Bushfire = any fire burning out of control (internationally: “wildfire”).
- A natural hazard can harm people & environments; a disaster when it does major damage.
- Double-edged: many species are fire-adapted, yet extreme fires devastate.

Section 2

# What controls a bushfire?

## The fire triangle & the “big three”

Fuel load

More dry leaf litter & bark = hotter fire.

Weather

High temp, low humidity, strong wind.

Topography

Fire runs faster uphill.

Fire needs heat + fuel + oxygen (the fire triangle). Ignition = lightning or humans; the big three decide how bad it gets.

Section 3

# How fire moves

## Fire behaviour

Embers start spot fires ahead of the front (so fires jump roads). Crown fires leap treetops; radiant heat is the main killer.

Section 4

# Slope & climate drivers

## Land shape & the climate cycle

- Slope: fire roughly doubles speed per 10° upslope.
- El Niño = hotter/drier (higher risk); La Niña = wetter (more growth → future fuel). Tracked by the SOI.
- The warming trend lengthens fire seasons (Chapter 13).

Section 5

# Fire in the landscape

## Fire-adapted ecosystems & cultural burning

Eucalypts resprout from epicormic buds; some seeds need fire's heat/smoke. Fire is woven into Australian ecosystems.

First Nations cultural burning — living knowledge

Aboriginal & Torres Strait Islander peoples have used cool, low-intensity cultural burning to care for Country for tens of thousands of years — reducing fuel and risk. Learn from endorsed sources: AIATSIS · NITV.

Section 6 · Case study

# A global hazard

## Wildfires worldwide

California & Greece

Record burn areas and deadly, fast-moving fires — driven by the same drought, heat & wind, and worsened by climate change. Comparing places sharpens management insight.

Scale Change Environment
Recap

# 14.1 in one screen

## Pull it together

- Bushfire = fire out of control; natural hazard.
- Fire triangle + big three: fuel, weather, topography.
- Behaviour: front, embers, spot fires, crown, radiant heat.
- Slope & climate (El Niño/La Niña; warming).
- Fire-adapted flora & cultural burning; global comparison.

Next: 14.2 — Bushfire mitigation strategies.

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