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 18, 2026
Oct. 18, 2026 A catastrophic volcanic eruption 7,300 years ago devastated Japan, but new research reveals that its impact on prehistoric populations was far more complex than previously believed. While some ...
Oct. 17, 2026 El Niño is fueling a dangerous cascade of wildfires across the tropics, with the Amazon rainforest now experiencing widespread burning and scientists warning that the worst may still be ahead. NASA researchers are uncovering dozens of previously ...
Oct. 17, 2026 Scientists have discovered that some forest soils are becoming surprisingly better at removing methane from the atmosphere as temperatures rise and rainfall declines. A study spanning up to 24 years found methane absorption increasing by an average ...
Oct. 16, 2026 Scientists have discovered a remarkable “Pac-Man enzyme” that helps bacteria devour certain types of plastic and may offer new hope in the fight against plastic pollution. Researchers found that ...
Oct. 15, 2026 Antarctic sea ice reached its third-lowest winter maximum in 2026, extending a remarkable decline that began after years of record-breaking growth. Scientists are investigating whether the dramatic reversal signals a long-term shift in Antarctica's ...
Oct. 15, 2026 Arctic sea ice is shrinking in both winter and summer, with satellite records revealing that the region's remaining ice is becoming thinner, younger, and more vulnerable to melting. Despite a recent slowdown in summer losses, scientists warn that ...
Oct. 15, 2026 Scientists have discovered a potential new weapon against a devastating fungus that threatens rice, wheat, and barley worldwide. By engineering a special type of plant immune receptor, researchers ...
Oct. 12, 2026 Europe's Sentinel-3C satellite has returned breathtaking images of Earth just two weeks after launch, revealing the snowy Alps, frozen Arctic islands, and brilliant turquoise Caribbean waters. Its ...
Oct. 12, 2026 Scientists may have solved a 2.3-billion-year-old mystery about how Earth maintained enough oxygen to support life. Ancient rocks reveal that phosphorus recycling in the oceans created a ...
Oct. 12, 2026 Australia's normally dry, rust-colored outback has erupted into a spectacular carpet of wildflowers after unusually heavy rains, potentially producing its most impressive bloom in nearly 20 years. NASA satellite images capture the stunning ...
Oct. 8, 2026 A brilliant yellow coral discovered off Costa Rica proved so unusual that scientists had to create an entirely new family to classify it. The meter-tall colonies rise from seafloors covered in brittle stars, inspiring the Tolkien-inspired name ...
Oct. 7, 2026 Earth’s center of mass is constantly on the move, shifting by a few millimeters as enormous amounts of water, ice, and even air migrate around the planet with the seasons. NASA scientists have developed a more precise way to track these tiny ...
Latest Headlines
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Oct. 16, 2026 As Hurricane Simon unleashed destructive winds and flooding along Mexico’s coast, NASA satellites captured an extraordinary sight: massive atmospheric waves rippling high above the storm. The rare ...
Oct. 11, 2026 An astronaut aboard the International Space Station photographed a remarkable formation in Madagascar that looks surprisingly similar to the Moon’s bright highlands. Made of anorthosite, a rock ...
Oct. 6, 2026 New research suggests animals could have evolved as early as 800 to 700 million years ago, roughly 200 million years earlier than some previous estimates. If so, the first animals may have lived ...
Oct. 4, 2026 A meteor crater buried beneath Oklahoma has turned out to be nearly 100 million years younger than scientists thought. Zircon crystals show the Ames impact occurred about 370 million years ago, ...
Oct. 4, 2026 A 30-year forestry experiment in Australia found that heavily thinned mountain ash forests grew unusually large trees while recovering enough carbon to match or exceed untouched areas. The results ...
Oct. 4, 2026 A new light-activated material can efficiently produce hydrogen from water without requiring an additional expensive metal catalyst. Researchers say its unusual sulfur-based chemistry could point ...
Oct. 2, 2026 Researchers say stress on Southern California’s San Andreas and San Jacinto faults has reached some of the highest levels seen in a 1,000-year ...
Oct. 1, 2026 A new protective fabric boosted strawberry yields by as much as 3.56 times while blocking insects and still allowing sunlight, rain, and airflow to reach the plants. Originally inspired by research ...
Sep. 30, 2026 Marine heatwaves may be only the most intense part of much longer warming events, with elevated temperatures sometimes lingering for months. Researchers found that conventional measurements ...
Sep. 30, 2026 Mount Vesuvius’ famous 79 CE eruption has given scientists a remarkably precise benchmark for dating events deep in Earth’s past. The improved ...