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Ice core
An ice core is a core sample from the accumulation of snow and ice over many years that have recrystallized and have trapped air bubbles from previous time periods. The composition of these ice cores, especially the presence of hydrogen and oxygen isotopes, provides a picture of the climate at the time.
Because water molecules containing heavier isotopes exhibit a lower vapor pressure, when the temperature falls, the heavier water molecules will condense faster than the normal water molecules. The relative concentrations of the heavier isotopes in the condensate indicate the temperature of condensation at the time, allowing for ice cores to be used in global temperature reconstruction. In addition to the isotope concentration, the air bubbles trapped in the ice cores allow for measurement of the atmospheric concentrations of trace gases, including greenhouse gases carbon dioxide, methane, and nitrous oxide. The air bubbles may also contain traces of aerosols, which are produced in great concentrations during volcanic eruptions.
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Earth & Climate News
December 28, 2025
Dec. 27, 2025 Scientists have built the most detailed 3D models yet of temperatures deep beneath Greenland. The results reveal uneven heat hidden below the ice, shaped by Greenland’s ancient path over a volcanic hotspot. This underground warmth affects how the ...
Dec. 25, 2025 Deep ocean hot spots packed with heat are making the strongest hurricanes and typhoons more likely—and more dangerous. These regions, especially near the Philippines and the Caribbean, are expanding as climate change warms ocean waters far below ...
Dec. 25, 2025 A new eco-friendly technology can capture and destroy PFAS, the dangerous “forever chemicals” found worldwide in water. The material works hundreds to thousands of times faster and more ...
Dec. 24, 2025 What we put on our plates may matter more for the climate than we realize. Researchers found that most people, especially in wealthy countries, are exceeding a “food emissions budget” needed to keep global warming below 2°C. Beef alone accounts ...
Dec. 24, 2025 The search for life on Earth is speeding up, not slowing down. Scientists are now identifying more than 16,000 new species each year, revealing far more biodiversity than expected across animals, plants, fungi, and beyond. Many species remain ...
Dec. 22, 2025 Washing machines release massive amounts of microplastics into the environment, mostly from worn clothing fibers. Researchers at the University of Bonn have developed a new, fish-inspired filter that removes over 99% of these particles without ...
Dec. 21, 2025 Scientists have uncovered a missing feedback in Earth’s carbon cycle that could cause global warming to overshoot into an ice age. As the planet warms, nutrient-rich runoff fuels plankton blooms that bury huge amounts of carbon in the ocean. In ...
Dec. 21, 2025 Old military air samples turned out to be a treasure trove of biological DNA, allowing scientists to track moss spores over 35 years. The results show mosses now release spores up to a month earlier than in the 1990s. Even more surprising, the ...
Dec. 19, 2025 New research reveals when glaciers around the world will vanish and why every fraction of a degree of warming could decide their ...
Dec. 18, 2025 Much of the western U.S. is overdue for wildfire, with decades of suppression allowing fuel to build up across millions of hectares. Researchers estimate that 74% of the region is in a fire deficit, meaning far more land needs to burn to restore ...
Dec. 15, 2025 Around 1,000 years ago, a major climate shift reshaped rainfall across the South Pacific, making western islands like Samoa and Tonga drier while eastern islands such as Tahiti became increasingly ...
Dec. 13, 2025 Researchers analyzing ancient fossils from caves across Western Australia have uncovered a completely new species of bettong along with two new woylie subspecies—remarkable finds made bittersweet by signs that some may already be ...
Latest Headlines
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Dec. 28, 2025 Scientists have uncovered why big predators like sharks spend so much time in the ocean’s twilight zone. The answer lies with mid-sized fish such as the bigscale pomfret, which live deep during the ...
Dec. 26, 2025 When Earth was a molten inferno, water may have been locked safely underground rather than lost to space. Researchers discovered that bridgmanite ...
Dec. 21, 2025 Researchers studying a massive landslide in Alaska have detected strange seasonal seismic pulses caused by water freezing and thawing in rock cracks. These faint signals could become an important ...
Dec. 19, 2025 Cosmic “touchdown airbursts” — explosions of comets or asteroids above Earth’s surface — may be far more common and destructive than previously thought, according to new research. Unlike ...
Dec. 16, 2025 A rare, ultra-long earthquake in Myanmar revealed that mature faults can deliver their full force directly to the surface. The discovery could mean stronger shaking near faults like California’s ...
Dec. 12, 2025 New research shows that crops are far more vulnerable when too much rainfall originates from land rather than the ocean. Land-sourced moisture leads to weaker, less reliable rainfall, heightening ...
Dec. 12, 2025 A sudden, unexplained mass die-off is decimating sea urchins around the world, including catastrophic losses in the Canary Islands. Key reef-grazing species are reaching historic lows, and their ...
Dec. 12, 2025 Fossils from Qatar have revealed a small, newly identified sea cow species that lived in the Arabian Gulf more than 20 million years ago. The site contains the densest known collection of fossil sea ...
Dec. 11, 2025 Researchers found that eroded lava rubble beneath the South Atlantic can trap enormous amounts of CO2 for tens of millions of years. These porous breccia deposits store far more carbon than ...
Dec. 11, 2025 Scientists tracking young Arizona Bald Eagles found that many migrate north during summer and fall, bucking the traditional southbound pattern of most birds. Their routes rely heavily on historic ...