--- title: "Rainforests & Global Climate" description: "Understand how rainforests affect climate. Growing trees use photosynthesis to absorb carbon dioxide, release oxygen and store carbon in wood. A forest is a carbon sink when it takes in more carbon th" canonical: https://lightmysky.com/learn/science/rainforests-and-global-climate-mt_HJd-8EEC6N source: https://lightmysky.com/learn/science/rainforests-and-global-climate-mt_HJd-8EEC6N.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`. # Rainforests & Global Climate Understand how rainforests affect climate. Growing trees use photosynthesis to absorb carbon dioxide, release oxygen and store carbon in wood. A forest is a carbon sink when it takes in more carbon than it releases. Burning or decay can return stored carbon as CO2, while clearing removes growing trees. Transpiration supplies moisture for rainfall, so losing trees can also change regional rain patterns. Subject: Science · Area: Rainforests · Ages 9 to 11 Page: https://lightmysky.com/learn/science/rainforests-and-global-climate-mt_HJd-8EEC6N ## Ready when they can - Explain that growing trees absorb CO2 and store carbon, and that a forest is a carbon sink when it takes in more carbon than it releases over the same period - Describe how burning or decay can release stored carbon as CO2, adding to warming, and how clearing also removes trees that would absorb CO2 - Explain that transpiration supplies moisture for rainfall, and that losing trees can change rain patterns without being the only possible cause ## Lesson: Rainforests: Nature's Carbon Bank Growing trees use sunlight, water and carbon dioxide (CO2) to make food. This is photosynthesis, which also releases oxygen. Some carbon becomes wood in trunks, branches and roots. Plants, animals and decaying material also return CO2 to the air. Over the same period, a forest is a carbon sink if it takes in more carbon than it releases. A forest can hold much carbon without being a sink. *(drawing: Some carbon from CO2 becomes part of growing wood. Storage can last for years, but burning or decay can release carbon.)* Clearing can affect CO2 even when no wood burns. Suppose growing trees are removed and no new trees replace them. The removed trees no longer take in CO2 through photosynthesis. Keeping their wood as furniture can store some carbon, but it does not keep the trees' CO2 uptake going. This loss of uptake is separate from carbon released by burning or decay. Burning wood combines its carbon with oxygen from the air to form CO2. Some carbon can remain in charcoal or unburned wood. Cutting does not release all carbon at once: furniture can store it for years. Decay returns carbon to the air, usually more slowly than burning. CO2 absorbs and sends out some of Earth's outgoing heat. Adding CO2 slows heat loss to space and increases warming, separate from the fire's heat. In the rainforest water cycle, roots take in water and leaves release water vapor. This release is transpiration. When moist air cools, water vapor can form tiny cloud droplets. Droplets can join together and fall as rain. With fewer trees, less water vapor enters the air through transpiration. Rainfall may decrease nearby or in places reached by that moist air. Winds and other weather changes also affect rain. Less rain after forest clearing fits what we know about transpiration, but it does not prove clearing was the only cause. Compare rainfall over several years and check other changes before reaching that conclusion. **Recap.** Growing trees store carbon and release water vapor. Burning or decay can return carbon as CO2. Losing trees can add to warming and change rainfall. *This lesson, practice and flashcards were written for this dataset. The forest carbon-balance figures are made-up practice values.* ## Practice 8 questions on this page, each with its working shown. ## Needs first - [Rainforest Water Cycle](https://lightmysky.com/learn/science/rainforest-water-cycle-mt_ZWTk6eP1qF) ## Optional connections - [Deforestation Causes & Scale](https://lightmysky.com/learn/science/deforestation-causes-and-scale-mt_2OSTHTWDpa) - [Climate Change Basics](https://lightmysky.com/learn/science/climate-change-basics-mt_DbI1kNg_0R) ## Opens up - [Rainforest Futures & Trade-Offs](https://lightmysky.com/learn/science/rainforest-futures-and-trade-offs-mt_ZM7u9m-gS4)