QUESTION 1 / 20 · CLIMATEEasy
Which greenhouse gas from human activity contributes most to global warming?
A TROPHIC CASCADE
Yellowstone, with and without wolves
When wolves returned, the effects rippled down from the top of the food chain to the plants, a pattern ecologists call a trophic cascade.
What this environmental science quiz covers, in short
Twenty multiple-choice questions, four in each of five areas: climate, ecosystems and biodiversity, energy, pollution and waste, and water and resources. They cover how natural systems work and how people affect them.
Figures like methane's warming power and energy shares change as research and markets move; we use widely cited recent values. The quiz is our own and not normed.
By What's Your IQ · Reviewed 4 Oct 2026- Format
- 20 multiple-choice questions, 4 options each
- Topics
- Climate, ecosystems, energy, pollution, water
- Bonus
- Yellowstone trophic-cascade explorer
- Level
- Easy to medium, a few hard
~2066when the Antarctic ozone hole is expected to healBecause almost every country banned ozone-destroying chemicals under the 1987 Montreal Protocol. It's often called the most successful environmental treaty.2
1962Silent Spring.Rachel Carson showed how the pesticide DDT moved up food chains, helping launch the modern environmental movement.
1987The Montreal Protocol.Countries agreed to phase out CFCs after the Antarctic ozone hole was reported in 1985.
1988The IPCC.The Intergovernmental Panel on Climate Change was set up to assess climate science for governments.
2015The Paris Agreement.Nearly every country set its own targets to limit warming to well below 2 °C.
- Carson, R. (1962). Silent spring. Houghton Mifflin.
- WMO/UNEP. (2022). Scientific assessment of ozone depletion: 2022. World Meteorological Organization.
- Ripple, W. J., & Beschta, R. L. (2012). Trophic cascades in Yellowstone: The first 15 years after wolf reintroduction. Biological Conservation, 145(1), 205–213.