--- title: "Greenhouse Gas Science" description: "Compare incoming short-wave solar radiation with Earth's outgoing long-wave infrared. Describe how suitable molecular vibrations let greenhouse gases absorb infrared, while O2 and N2 absorb very littl" canonical: https://lightmysky.com/learn/science/greenhouse-gas-science-mt_EQQWKz03P8 source: https://lightmysky.com/learn/science/greenhouse-gas-science-mt_EQQWKz03P8.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Greenhouse Gas Science Compare incoming short-wave solar radiation with Earth's outgoing long-wave infrared. Describe how suitable molecular vibrations let greenhouse gases absorb infrared, while O2 and N2 absorb very little. Explain the natural greenhouse effect and its strengthening by human emissions. Interpret gas warming comparisons for equal released masses over a stated time. Subject: Science · Area: Weather & Climate · Ages 11 to 12 Page: https://lightmysky.com/learn/science/greenhouse-gas-science-mt_EQQWKz03P8 ## Ready when they can - Compare short-wave solar radiation with Earth's long-wave infrared emissions - Identify greenhouse gases and explain why suitable molecular vibrations absorb infrared - Describe infrared absorption, energy transfer through collisions and infrared emission - Distinguish the natural greenhouse effect from its strengthening by human emissions - Interpret a stated equal-mass, 100-year warming comparison and explain why emission amounts and timing also matter ## Lesson: Why Some Gases Trap Heat and Others Don't You have seen how sunlight warms land and water. Light carries energy as electromagnetic radiation. Wavelength is the spacing between neighboring wave crests. The electromagnetic spectrum groups radiation by wavelength. Sunlight includes visible light, ultraviolet and near-infrared. Earth's cooler surface emits mostly long-wave infrared. Solar radiation is called short-wave in comparison. Infrared is invisible; absorbing it can warm matter. *(drawing: Read from longer to shorter wavelengths. The boxes show order, not a scale.)* Greenhouse gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and water vapor (H2O). Their bonded atoms vibrate, moving back and forth. They absorb certain infrared wavelengths when a vibration changes their electric dipole. This is the size or direction of the separation between positive and negative charge in the molecule. Oxygen (O2) and nitrogen (N2) also vibrate. Their atoms can stretch apart and move together, but this does not change their electric dipole. They absorb very little of Earth's outgoing infrared. CO2 gains vibration energy by absorbing matching infrared. Collisions can pass energy to nearby air molecules. Greenhouse gases also emit infrared in many directions, including toward the surface. The absorbing molecule need not emit immediately. Greenhouse gases occur naturally. By absorbing and emitting infrared, they keep Earth's surface warmer than it would be without them. This natural greenhouse effect helps keep Earth warm enough for liquid water and life. It existed before human industry. Removing it would leave Earth's average surface colder. Human activities add greenhouse gases. Burning coal, oil and gas releases CO2. Fuel leaks and farming release methane. With the same incoming sunlight, added greenhouse gases initially reduce energy escaping to space. Earth warms, and outgoing energy increases toward a new balance. This strengthening of the natural effect is the enhanced greenhouse effect. Global warming potential (GWP) compares the warming effects of equal released masses over a stated time. CO2 has a score of 1. A 100-year GWP adds up the effects over 100 years after release. The score reflects infrared absorption and how long the gas affects the atmosphere. A historical score of 265 for nitrous oxide means 265 divided by 1, or 265 times CO2's effect for equal masses. It is not a per-molecule rating. *(drawing: IPCC 2013: 100-year GWP without climate-carbon feedbacks. Equal released masses: CO2 = 1, methane = 28, nitrous oxide = 265.)* People release different amounts of each gas. To judge total warming, also consider how much was released and when. A smaller release of a high-GWP gas need not cause more warming than a much larger release of a lower-GWP gas. An equal-mass score alone cannot tell you which gas makes the larger total contribution. **Recap.** Greenhouse gases absorb and emit some infrared. Human emissions strengthen the natural effect. Compare warming scores for equal released masses over the same time, not molecule by molecule. *Lesson, questions and flashcards written for this dataset. Historical gas comparisons use IPCC 2013 estimates for equal released masses over 100 years, without climate-carbon feedbacks.* ## Practice 8 questions on this page, each with its working shown. ## Needs first - [Sun-Driven Weather Systems](https://lightmysky.com/learn/science/sun-driven-weather-systems-mt_-YYnLLIZh5) ## Opens up - [Human Impact on Ecosystems: Land, Waste and a Warming World](https://lightmysky.com/learn/science/human-impact-on-ecosystems-land-waste-and-a-warming-world-mt_BiYCyohfyI) - [Earth's Energy Balance and the Greenhouse Effect, Quantified](https://lightmysky.com/learn/science/earths-energy-balance-and-the-greenhouse-effect-quantified-mt_dDV2fr06nO) - [Energy stores and transfers](https://lightmysky.com/learn/science/energy-stores-and-transfers-mt_Jvg_r4yWaY) - [Earth's Atmosphere & CO2](https://lightmysky.com/learn/science/earths-atmosphere-and-co2-mt_mTpV-0rtkO)