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Reference Terms
from Wikipedia, the free encyclopedia

Carbon dioxide

Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. It is often referred to by its formula CO2. It is present in the Earth's atmosphere at a low concentration and acts as a greenhouse gas. In its solid state, it is called dry ice. It is a major component of the carbon cycle.

Atmospheric carbon dioxide derives from multiple natural sources including volcanic outgassing, the combustion of organic matter, and the respiration processes of living aerobic organisms; man-made sources of carbon dioxide come mainly from the burning of various fossil fuels for power generation and transport use. It is also produced by various microorganisms from fermentation and cellular respiration. Plants convert carbon dioxide to oxygen during a process called photosynthesis, using both the carbon and the oxygen to construct carbohydrates. In addition, plants also release oxygen to the atmosphere, which is subsequently used for respiration by heterotrophic organisms, forming a cycle.

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Earth & Climate News

February 27, 2026

Antarctica’s Hektoria Glacier stunned scientists by retreating eight kilometers in just two months, with nearly half of it collapsing in record time. The rapid breakup was driven by a flat, underwater bedrock surface that allowed the glacier to ...
A lost cache of 250-million-year-old fossils from Australia has rewritten part of the story of life after Earth’s worst mass extinction. Instead of a single marine amphibian species, researchers ...
Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already ...
Deep in the Congo Basin, vast peatlands quietly store enormous amounts of Earth’s carbon — but new research suggests this ancient vault may be leaking. Scientists studying Africa’s largest ...
A new 30-year analysis reveals that melting land ice is now the main force behind rising global sea levels. Researchers discovered that oceans rose about 90 millimeters since 1993, with most of the increase coming from added water mass rather than ...
Deep in the Arctic north, drained peatlands—once massive carbon vaults built over thousands of years—are quietly leaking greenhouse gases into the atmosphere. But new field research from northern Norway suggests there’s a powerful way to slow ...
Flea and tick medications trusted by pet owners worldwide may have an unexpected environmental cost. Scientists found that active ingredients from isoxazoline treatments pass into pet feces, exposing dung-feeding insects to toxic chemicals. These ...
Ocean waves are a vast and steady source of renewable energy, but capturing their power efficiently has long frustrated engineers. A researcher at The University of Osaka has now explored a bold new approach: a gyroscopic wave energy converter that ...
As the planet warms, many expected ecosystems to change faster and faster. Instead, a massive global study shows that species turnover has slowed by about one-third since the 1970s. Nature’s constant reshuffling appears to be driven more by ...
NASA has pulled off a high-flying aurora investigation, launching three rockets into the glowing northern lights over Alaska. One mission targeted mysterious dark patches called black auroras, while ...
For years, satellite data suggested that autumn snow cover in the Northern Hemisphere was actually increasing — a surprising twist in a warming world. But a new analysis reveals that this apparent growth was an illusion caused by improving ...
Even Antarctica’s toughest native insect can’t escape the reach of plastic pollution. Scientists have discovered that Belgica antarctica — a tiny, rice-sized midge and the southernmost insect on Earth — is already ingesting microplastics in ...

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