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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

October 8, 2025

The Amazon has suffered its most destructive fire season in more than two decades, releasing a staggering 791 million tons of carbon dioxide—on par with Germany’s annual emissions. Scientists found that for the first time, fire-driven ...
Researchers at KAUST have confirmed that the Red Sea once vanished entirely, turning into a barren salt desert before being suddenly flooded by waters from the Indian Ocean. The flood carved deep channels and restored marine life in less than ...
Marine heatwaves can jam the ocean’s natural carbon conveyor belt, preventing carbon from reaching the deep sea. Researchers studying two major heatwaves in the Gulf of Alaska found that plankton shifts caused carbon to build up near the surface ...
Solar energy is now the cheapest source of power worldwide, driving a massive shift toward renewables. Falling battery prices and innovations in solar materials are making clean energy more reliable than ever. Yet, grid congestion and integration ...
New research reveals that deep-sea mining could dramatically threaten 30 species of sharks, rays, and ghost sharks whose habitats overlap with proposed mining zones. Many of these species, already at risk of extinction, could face increased dangers ...
Billions of years ago, Earth’s atmosphere was hostile, with barely any oxygen and toxic conditions for life. Researchers from the Earth-Life Science Institute studied Japan’s iron-rich hot springs, which mimic the ancient oceans, to uncover how ...
In 2020, California’s Creek Fire became so intense that it generated its own thunderstorm, a phenomenon called a pyrocumulonimbus cloud. For years, scientists struggled to replicate these explosive fire-born storms in climate models, leaving major ...
Swiss glaciers lost nearly 3% of their volume in 2025, following a snow-poor winter and scorching summer heatwaves. The melt has been so extreme that some glaciers lost more than two meters of ice thickness in a single season. Scientists caution ...
Fungi may have shaped Earth’s landscapes long before plants appeared. By combining rare gene transfers with fossil evidence, researchers have traced fungal origins back nearly a billion years earlier than expected. These ancient fungi may have ...
Scientists have uncovered an unexpected witness to Earth’s distant past: tiny iron oxide stones called ooids. These mineral snowballs lock away traces of ancient carbon, revealing that oceans between 1,000 and 541 million years ago held far less ...
Scientists found that biochar doesn’t just capture pollutants, it actively destroys them using direct electron transfer. This newly recognized ability accounts for up to 40% of its cleaning power and remains effective through repeated use. The ...
Bio-tar, once seen as a toxic waste, can be transformed into bio-carbon with applications in clean energy and environmental protection. This innovation could reduce emissions, create profits, and solve a major bioenergy industry ...

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updated 12:56 pm ET