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
October 29, 2025
Oct. 29, 2025 — Global scientists warn that humanity is on the verge of crossing irreversible climate thresholds, with coral reefs already at their tipping point and polar ice sheets possibly beyond recovery. The Global Tipping Points Report 2025 reveals how rising ...
Oct. 29, 2025 — Researchers at QUT uncovered how corals reattach to reefs through a three-phase process involving tissue transformation, anchoring, and skeleton formation. Differences among species reveal why some corals grow and attach faster than others. ...
Oct. 29, 2025 — Beneath the ice of Antarctica’s Weddell Sea, scientists discovered a vast, organized city of fish nests revealed after the colossal A68 iceberg broke away. Using robotic explorers, they found over ...
Oct. 27, 2025 — Extinction rates are not spiraling upward as many believe, according to a large-scale study analyzing 500 years of data. Researchers found that species losses peaked about a century ago and have decreased since, with different drivers shaping past ...
Oct. 27, 2025 — The Southern Ocean absorbs nearly half of all ocean-stored human CO2, but its future role is uncertain. Despite models predicting a decline, researchers found that freshening surface waters are currently keeping deep CO2 trapped below. This ...
Oct. 27, 2025 — A team of researchers has developed a floral-scented fungus that tricks mosquitoes into approaching and dying. The fungus emits longifolene, a natural scent that irresistibly draws them in. It’s harmless to humans, inexpensive to produce, and ...
Oct. 26, 2025 — New research shows that hippos lived in central Europe tens of thousands of years longer than previously thought. Ancient DNA and radiocarbon dating confirm they survived in Germany’s Upper Rhine Graben during a milder Ice Age phase. Closely ...
Oct. 26, 2025 — Scientists have uncovered that glaciers can temporarily cool the air around them, delaying some effects of global warming. This self-cooling, driven by katabatic winds, is nearing its peak and will likely reverse in the next two decades. Once ...
Oct. 25, 2025 — For the first time, scientists have seen a subduction zone actively breaking apart beneath the Pacific Northwest. Seismic data show the oceanic plate tearing into fragments, forming microplates in a slow, step-by-step collapse. This process, once ...
Oct. 24, 2025 — Scientists have discovered that El Niño and La Niña could become far more powerful and predictable as the planet warms. By 2050, the tropical Pacific may hit a tipping point, locking ENSO into strong, rhythmic oscillations that synchronize with ...
Oct. 23, 2025 — In the mist-shrouded mountains of New Guinea, a Czech researcher has achieved a world-first — capturing photos, video, and data of the elusive Subalpine Woolly Rat, Mallomys istapantap. Once known only from museum specimens, this giant, shaggy ...
Oct. 23, 2025 — Sea levels are rising faster than at any time in 4,000 years, scientists report, with China’s major coastal cities at particular risk. The rapid increase is driven by warming oceans and melting ice, while human activities like groundwater pumping ...
Latest Headlines
updated 12:56 pm ET
Oct. 28, 2025 — Fungi’s evolutionary roots stretch far deeper than once believed — up to 1.4 billion years ago, long before plants or animals appeared. Using advanced molecular dating and gene transfer analysis, ...
Oct. 28, 2025 — Scientists have traced the origins of complex life to the breakup of the supercontinent Nuna 1.5 billion years ago. This tectonic shift reduced volcanic carbon emissions, expanded shallow seas, and ...
Oct. 27, 2025 — New research shows that the rise of Sumer was deeply tied to the tidal and sedimentary dynamics of ancient Mesopotamia. Early communities harnessed predictable tides for irrigation, but when deltas ...
Oct. 27, 2025 — A massive crater hidden beneath the Atlantic seafloor has been confirmed as the result of an asteroid strike from 66 million years ago. The new 3D ...
Oct. 27, 2025 — Researchers traced tremor signals deep inside Tanzania’s Oldoinyo Lengai volcano, pinpointing their 3D locations for the first time. The study ...
Oct. 23, 2025 — Scientists have uncovered evidence that megaquakes in the Pacific Northwest might trigger California’s San Andreas Fault. A research ship’s ...
Oct. 22, 2025 — Common dolphins in the North Atlantic are living significantly shorter lives, with female longevity dropping seven years since the 1990s. Researchers found this decline by analyzing stranded ...
Oct. 21, 2025 — Scientists are taking the once-radical concept of dimming the sun through stratospheric aerosol injection (SAI) seriously, but a Columbia University team warns that reality is far messier than models ...
Oct. 21, 2025 — Melting Arctic ice is revealing a hidden world of nitrogen-fixing bacteria beneath the surface. These microbes, not the usual cyanobacteria, enrich the ocean with nitrogen, fueling algae growth that ...
Oct. 19, 2025 — Researchers have developed a light-emitting sugar probe that exposes how marine microbes break down complex carbohydrates. The innovative fluorescent tool allows scientists to visualize when and ...