Reference Terms
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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
January 29, 2026
Jan. 29, 2026 Scientists studying ancient ocean fossils found that the Arabian Sea was better oxygenated 16 million years ago, even though the planet was warmer than today. Oxygen levels only plunged millions of years later, after the climate cooled, defying ...
Jan. 29, 2026 Small mammals are early warning systems for environmental damage, but many species look almost identical, making them hard to track. Scientists have developed a new footprint-based method that can tell apart nearly indistinguishable species with ...
Jan. 29, 2026 Scientists have created a device that captures carbon dioxide and transforms it into a useful chemical in a single step. The new electrode works with realistic exhaust gases rather than requiring purified CO2. It converts the captured gas into ...
Jan. 25, 2026 After analyzing 40 years of tree records across the Andes and Amazon, researchers found that climate change is reshaping tropical forests in uneven ways. Some regions are steadily losing tree species, especially where conditions are hotter and ...
Jan. 21, 2026 A new building material developed by engineers at Worcester Polytechnic Institute could change how the world builds. Made using an enzyme that turns carbon dioxide into solid minerals, the material cures in hours and locks away carbon instead of ...
Jan. 21, 2026 Mountain regions around the world are heating up faster than the lands below them, triggering dramatic shifts in snow, rain, and water supply that could affect over a billion people. A major global review finds that rising temperatures are turning ...
Jan. 19, 2026 Plastic-coated fertilizers used on farms are emerging as a major but hidden source of ocean microplastics. A new study found that only a tiny fraction reaches beaches through rivers, while direct drainage from fields to the sea sends far more ...
Jan. 17, 2026 Tiny plastic particles drifting through the oceans may be quietly weakening one of Earth’s most powerful climate defenses. New research suggests microplastics are disrupting marine life that helps oceans absorb carbon dioxide, while also releasing ...
Jan. 15, 2026 New research shows tropical forests can recover twice as fast after deforestation when their soils contain enough nitrogen. Scientists followed forest regrowth across Central America for decades and found that nitrogen plays a decisive role in how ...
Jan. 15, 2026 In the rapidly disappearing Atlantic Forest, mosquitoes are adapting to a human-dominated landscape. Scientists found that many species now prefer feeding on people rather than the forest’s diverse wildlife. This behavior dramatically raises the ...
Jan. 14, 2026 For thousands of years, wildfires on Alaska’s North Slope were rare. That changed sharply in the 20th century, when warming temperatures dried soils and fueled the spread of shrubs, setting the stage for intense fires. Peat cores and satellite ...
Jan. 14, 2026 Scientists have identified a newly recognized threat lurking beneath the ocean’s surface: sudden episodes of underwater darkness that can last days or even months. Caused by storms, sediment runoff, algae blooms, and murky water, these “marine ...
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Jan. 27, 2026 The Ediacara Biota are some of the strangest fossils ever found—soft-bodied organisms preserved in remarkable detail where preservation shouldn’t be possible. Scientists now think their survival ...
Jan. 23, 2026 Rare rocks buried deep in central Australia have revealed how a valuable niobium deposit formed during the breakup of an ancient supercontinent. More than 800 million years ago, tectonic rifting ...
Jan. 17, 2026 Scientists are uncovering a hidden and surprisingly complex earthquake zone beneath Northern California by tracking swarms of tiny earthquakes that are far too weak to feel. These faint tremors are ...
Jan. 16, 2026 Hydrogen cyanide, a toxic chemical, may have helped spark the chemistry that led to life. When frozen, it forms crystals with highly reactive surfaces that can drive unusual chemical reactions, even ...
Jan. 14, 2026 Earth’s oceans reached their highest heat levels on record in 2025, absorbing vast amounts of excess energy from the atmosphere. This steady buildup has accelerated since the 1990s and is now ...
Jan. 13, 2026 Honey bees can normally keep their hives perfectly climate-controlled, but extreme heat can overwhelm their defenses. During a scorching Arizona summer, researchers found that high temperatures ...
Jan. 13, 2026 Scientists tracking Earth’s water from space discovered that El Niño and La Niña are synchronizing floods and droughts across continents. When these climate cycles intensify, far-apart regions ...
Jan. 12, 2026 Plastic pollution is not just in oceans and soil. Scientists have now found enormous amounts of microscopic plastic floating through urban air, far exceeding earlier estimates. Road dust and rainfall ...
Jan. 12, 2026 Microscopic ocean algae produce a huge share of Earth’s oxygen—but they need iron to do it. New field research shows that when iron is scarce, phytoplankton waste energy and photosynthesis ...
Jan. 10, 2026 Crystals hidden in Australia’s oldest rocks have revealed new clues about how Earth and the Moon formed. The study suggests Earth’s continents didn’t begin growing until hundreds of millions of ...