---
title: "What are Earth's spheres?"
subtitle: "Year 9 Earth and space · The carbon cycle · Lesson 1"
---

# What are Earth's spheres?

**Name:** {{field-24}} **Date:** {{field-15}} **Class:** {{field-15}}

> **Key question:** A single bushfire involves all of Earth: burning trees, smoke in the air, ash washed into rivers and scorched soil. Scientists use four 'spheres' to keep track of it.


:::teacher-note

**In one sentence:** Students name and describe Earth's four spheres, give examples of matter and processes in each, and recognise that spheres overlap and interact (AC9S9U03, node 1, a hinge node).

**Students should be able to say:** I can name the four spheres and say what each contains. I can give an example of matter in each sphere. I can explain that the spheres interact, with examples where they meet.

**Width:** the unmarked parts are the floor every student does (Engage, Explore, Explain, Evaluate). Typical and Wider sections add contexts, not difficulty. Students work in the online tutorial alongside this sheet.

:::


## Engage


:::keep-together

**Soil is made of broken-down rock, water, air and living things. Which sphere is it part of?**

☐ Biosphere only

☐ More than one: it's where spheres meet

☐ Geosphere only

☐ None of them

My prediction, and why:

{{lines-3}}

:::


:::teacher-note

**What happens:** More than one. Soil is mostly broken rock (geosphere) full of living things and their remains (biosphere), with water and air in its gaps. The spheres overlap and interact.

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## Explore

Try it on the board in the tutorial. Was your prediction right? What was different?

{{lines-2}}

## Explain: four spheres, one system


:::keep-together

### Contents

**Match each sphere to what it contains.**

A. All living things

B. Rock, soil, minerals and magma

C. All water: oceans, rivers, ice, vapour

D. The layer of gases around Earth

{{columns 60% 40%}}

{{rows 1}}

| Part | Letter |
|---|---|
| `Atmosphere` | |
| `Biosphere` | |
| `Hydrosphere` | |
| `Geosphere` | |

:::


:::teacher-note

**Answer:** Atmosphere → D. The layer of gases around Earth; Biosphere → A. All living things; Hydrosphere → C. All water: oceans, rivers, ice, vapour; Geosphere → B. Rock, soil, minerals and magma

:::


:::keep-together

### Interactions

**A tree takes in carbon dioxide and water to grow. Which spheres does this connect?**

☐ Only the atmosphere

☐ Geosphere and atmosphere

☐ Atmosphere (CO₂), hydrosphere (water) and biosphere (the tree)

☐ Only the biosphere

:::


:::teacher-note

**Answer:** Atmosphere (CO₂), hydrosphere (water) and biosphere (the tree)

:::


:::keep-together

### Processes

**Match each sphere to a process that happens in it.**

A. A kangaroo eating grass

B. Wind carrying smoke from a bushfire

C. Ocean currents carrying water around the world

D. Rock slowly breaking down into soil

{{columns 60% 40%}}

{{rows 1}}

| Part | Letter |
|---|---|
| `Atmosphere` | |
| `Biosphere` | |
| `Hydrosphere` | |
| `Geosphere` | |

:::


:::teacher-note

**Answer:** Atmosphere → B. Wind carrying smoke from a bushfire; Biosphere → A. A kangaroo eating grass; Hydrosphere → C. Ocean currents carrying water around the world; Geosphere → D. Rock slowly breaking down into soil

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:::typical

## Elaborate: a rain event


:::keep-together

**A storm rolls in over farmland. Which sphere is each part mainly about?**

Groups: Atmosphere, Biosphere, Hydrosphere, Geosphere

- Wind and falling air pressure: {{field-15}}
- Rain filling the creek: {{field-15}}
- Topsoil washed off a paddock: {{field-15}}
- Crops growing faster after the rain: {{field-15}}

:::


:::teacher-note

**Answer:** Wind and falling air pressure → Atmosphere; Rain filling the creek → Hydrosphere; Topsoil washed off a paddock → Geosphere; Crops growing faster after the rain → Biosphere

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:::


:::wider

## Elaborate: managing interactions


:::keep-together

**For tens of thousands of years, many First Nations peoples have used small, cool fires to manage Country. Which spheres does a cool burn involve?**

☐ Only the biosphere

☐ All four: plants burn (biosphere), smoke and CO₂ enter the air (atmosphere), soil is warmed and enriched (geosphere), and later rain and regrowth (hydrosphere, biosphere)

☐ None: fire isn't part of the spheres

☐ Only the atmosphere

:::


:::teacher-note

**Answer:** All four: plants burn (biosphere), smoke and CO₂ enter the air (atmosphere), soil is warmed and enriched (geosphere), and later rain and regrowth (hydrosphere, biosphere)

:::

:::


## Evaluate: look back

Write one sentence: "At first I thought… Now I think… because…"

**Revision summary**

- **Atmosphere:** air. **Biosphere:** living things. **Hydrosphere:** water. **Geosphere:** rock, soil, magma.
- Many things sit where spheres meet (soil, clouds), and processes move matter between spheres.
- Earth works as one system of interacting spheres.

## Exit ticket

:::keep-together

**Name the four spheres and give one example of something where two of them meet.**

{{lines-3}}

:::


:::teacher-note

**Answer:** Atmosphere, biosphere, hydrosphere, geosphere. For example, soil (geosphere and biosphere) or a cloud (atmosphere and hydrosphere).

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