Models
What is a model?
A model is a simplified version of reality.
Models help us understand how a system works and what might happen if conditions change.
They are used because real systems are usually too complex to study in full.
A model is a simplified representation of reality used to understand, explain, or predict a system.
Why do models simplify reality?
Models do not include every detail of the real world.
When creating a model, scientists choose:
- what information is important
- what details can be left out
This makes models easier to understand and use, but less accurate than reality.
All models involve a trade-off: simpler models are easier to use but less precise.
Examples of models
The water cycle
[Diagram: water-cycle] - Available in full study mode
Shows evaporation, condensation and precipitation.
A food chain
[Diagram: food-chain] - Available in full study mode
Shows feeding relationships between organisms.
A population graph
[Diagram: population-graph] - Available in full study mode
Shows how population size changes over time.
A climate model
[Diagram: climate-model] - Available in full study mode
Uses data and equations to predict future climate conditions.
None of these models show every detail of the real system.
Types of models
Types of models
Uses of models
Models help us to:
⚠️ Example:
Climate models help predict future temperature rise under different emission scenarios.
Limitations of models
Because models are simplified, they have limitations.
If assumptions are wrong, conclusions can also be wrong.
Models and values
Models are influenced by:
As new knowledge is gained, models must be updated.
💡 Key idea:
Models should never be treated as perfect or final.
Models of sustainability
Different models have been used to show the relationship between environment, society, and economy.
Old Model (Equal Pillars)
Modern Model (Nested)
This highlights that environmental protection is essential for long-term sustainability.
Exam tips
Exam tips
One-sentence summary
Models simplify reality to help us understand and predict systems, but this simplification always causes loss of accuracy.
Summary: Models in ESS
What is a model?
A model is a **simplified representation of reality** used to understand, explain, or predict a system.
Why we need models: Real environmental systems are too complex to study in full. Models help us focus on the most important features.
Key terms
Key points
What to remember for the exam
Exam Tips:
- Always include the idea of **simplification** and **purpose** (understand, explain, or predict).
- If asked for an example, name the model AND say what it shows (e.g. a food chain shows feeding relationships).