What You Need to Know

Key Concept Diagram

Evidence includes rising global temperatures, melting ice caps, rising sea levels, and ocean acidification

The greenhouse effect is the natural warming process; enhanced by increased CO2 and methane

Human activities (burning fossil fuels, deforestation) increase greenhouse gas concentrations

Climate models use physics and mathematics to project future change under different emission scenarios

Key Vocabulary

Greenhouse effect

The trapping of heat in Earth's atmosphere by greenhouse gases

Greenhouse gas

A gas that absorbs infrared radiation (CO2, methane, water vapour)

Global warming

The long-term increase in Earth's average surface temperature

Sea level rise

The increase in ocean levels due to melting ice and thermal expansion of warming water

Knowledge Check

Select the correct answer for each question. Click "Check Answer" to see if you are right.

Question 1

Which of the following is NOT evidence for current climate change?

Rising average global temperatures The fact that Earth has always had some natural climate variation in the past Rising sea levels Retreating glaciers worldwide

Question 2

How do fossil fuels contribute to climate change?

By removing oxygen from the atmosphere By cooling the oceans By releasing CO2 and other greenhouse gases when burned, enhancing the greenhouse effect By reducing biodiversity

Question 3

Why is ocean acidification a concern related to climate change?

It increases sea levels It creates more hurricanes It cools the ocean, reducing evaporation It dissolved CO2 makes oceans more acidic, threatening marine organisms with calcium carbonate shells

Climate Change Evidence