BiologyGrade 12Climate Change

Climate Lab: Greenhouse Effect, Albedo, and Temperature

Adjust greenhouse gases, albedo, cloud cover, and solar input to compare absorbed sunlight, trapped infrared energy, and equilibrium temperature.

Textbook unitClimate ChangeGrade 12 Biology Unit 6
Keywordsclimate change, greenhouse effect, albedo, carbon dioxide, temperatureMapped to available textbook headings
Practice modeManipulate, measure, explainUse the controls, then read the live evidence

Environmental Science · Grade 11

Balance sunlight, reflection, and trapped heat

Adjust greenhouse gases, surface reflectivity, cloud cover, and solar input to compare absorbed sunlight, trapped infrared, and global temperature.

Climate stateNear balance
1

Pre-industrial baseline (CO₂ 280 ppm): load the preset and record temperature. This is your control trial.

2

Current atmosphere (CO₂ 420 ppm, CH₄ 1900 ppb): note how much forcing and temperature have changed from baseline.

3

Compensate: keep CO₂ at 420 ppm but raise albedo and cloud cover until temperature returns near baseline. What trade-offs emerge?

PhETGreenhouse Effect
Solar340 W/m²
15.2 °C
Energy balance1.5 W/m²210.8 W/m² outgoing IR
Absorbed sunlight212 W/m²
Effective albedo38%
Trapped infrared26 W/m²
Climate insight

Near energy balance: absorbed solar ≈ outgoing IR. Temperature 15.2 °C. Forcing terms nearly cancel — small changes in GHGs tip the balance.

Temperature15.2 °C
Net forcing1.5 W/m²
CO2 forcing2.2 W/m²
CH4 forcing0.6 W/m²
Cloud infrared8.0 W/m²

Lab task

Raise CO2, then adjust albedo or cloud cover until temperature returns near the starting value. Record both states and compare the forcing terms.

Observation rule

Climate temperature depends on energy balance: absorbed sunlight warms the surface, while albedo reflects sunlight and greenhouse gases reduce outgoing infrared loss.

Mission

What to prove in this lab

  1. Explain how greenhouse gas concentration changes outgoing infrared energy.
  2. Compare how albedo and cloud cover affect absorbed solar radiation.
  3. Use energy balance to predict whether surface temperature rises or falls.