Whole Earth Curriculum WEC

Lesson 08 — Why Is the Earth Warming?

Learners learn the **basic science of climate change** — greenhouse gases trapping heat — and the main **human activities** that add greenhouse gases. They label the greenhouse diagram and sort the activities that are heating the atmosphere.

D10 P4: Contextual & Ecological Awareness D10.S4 50 minutes Draft

Objectives

Essential question

What is the basic science of climate change, and which human activities add to it?

climate changegreenhouse gascarbon dioxidefossil fuelatmospheretrap

Materials

Standard materials

Low-tech / no-cost

Enriched / lab & device

Works in different contexts

A diagram of the greenhouse effect — the Sun's energy reaches the Earth's surface, and a layer of greenhouse gases traps some of the heat, with the note that greenhouse gases trap heat
A diagram of the greenhouse effect — the Sun's energy reaches the Earth's surface, and a layer of greenhouse gases traps some of the heat, with the note that greenhouse gases trap heat

Lesson 8 — Why Is the Earth Warming?

Summary

Learners learn the basic science of climate change: the Sun’s energy reaches Earth, and a layer of greenhouse gases traps some of the heat, warming the planet. They then identify the main human activities that add greenhouse gases — burning fossil fuels, cutting forests, farming, and industry.

Objectives

  • Explain the basic science of climate change (greenhouse gases trapping heat) and the main human activities that add to it. (D10.S4.07.01)

Connection

Have you ever sat in a closed car or a covered spot on a sunny day and felt it grow warm inside? The glass lets sunlight in but slows the heat from leaving. Earth’s atmosphere does something similar: certain gases — called greenhouse gases — let sunlight through but hold some of the heat near the surface. That holding is natural and keeps our planet warm enough to live on. The problem is that human activity has added so much more of those gases that the “blanket” has grown thicker, and the planet is warming.

Materials

  • Greenhouse-effect sheet
  • Activity cards

Preparation

  • Copy the greenhouse-effect sheet and activity cards.
  • Retrieval: from Lesson 6, recall that carbon cycles — and that burning buried carbon (fossil fuel) pushes extra carbon into the air. Today we see what that extra carbon does to the temperature.

Facilitator note

This lesson is written to the learner (“you”). The ideas to land: (1) the greenhouse effect is real and natural — the Sun’s energy comes in, and greenhouse gases trap some of the heat so Earth is warm enough for life; (2) human activities — burning fossil fuels (coal, oil, gas), cutting forests, some farming, and industry — add extra greenhouse gases, thickening the blanket; (3) that is why the Earth is warming, and the warming is a fact, not an opinion. Model the diagram once (worked example, S-011). The environment & technology lens: the warming is a direct bridge between human technology (burning fuel) and the living Earth — the unit’s central connection. The ethics lens: the science tells us what is happening; what we owe to others because of it is a value question, kept distinct. The egalitarian lens: the warming falls hardest on people who contributed least to it — an injustice we will return to in the next lesson. The global lens: this is a planet-wide change, measured the same way everywhere — and communities who live close to the land and sea, including many Indigenous peoples, have long noticed shifting seasons, weather, and wildlife through their own observation traditions, held side by side with the climate science here (philosophy §11). Hold the science precisely and cite it: the greenhouse effect and the role of human emissions are documented by the IPCC (S-005) and NOAA (S-309); warming also threatens health (S-124). End with agency, not despair — the next lesson is about action.

Procedure

  1. Recall (5 min). What happens to carbon when we burn buried fuel? Today we see what that extra carbon does to the temperature.
  2. Meet the greenhouse effect (12 min). Sunlight reaches Earth and warms the surface. Some heat rises back toward space, but a layer of greenhouse gases — including carbon dioxide — holds some of it near the surface. This is natural and keeps Earth warm enough for life.
  3. Label the diagram (10 min). On your sheet, label the Sun, the incoming energy, the surface, and the layer of greenhouse gases. Draw an arrow for the heat that is trapped.
  4. Sort the activities (15 min). With a group, sort the activity cards: burning coal, oil, and gas; cutting forests; some kinds of farming; and industry all add greenhouse gases. For each, say what gas or change it adds.
  5. Close (8 min). Share one activity you can now explain. Remember: the warming is real, it has a cause we can name, and — as we will see next — we can act on it.

Differentiation

  • Support: Provide the diagram labels in a word bank and ask learners to place them, then match each activity to the gas it adds.
  • Extension: Using a simple data table, rank the main activities by how much they add and explain your ranking.

Assessment

  • Formative (observation): Can the learner explain how greenhouse gases trap heat and name at least two human activities that add them?
  • Portfolio artifact: The labeled greenhouse diagram, kept in the portfolio.

Home connection

Explain the greenhouse effect to someone at home using the blanket or closed-car example, and name one thing your household does that adds greenhouse gases and one that does not.

Resources