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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
February 27, 2026
Feb. 26, 2026 Antarctica’s Hektoria Glacier stunned scientists by retreating eight kilometers in just two months, with nearly half of it collapsing in record time. The rapid breakup was driven by a flat, underwater bedrock surface that allowed the glacier to ...
Feb. 25, 2026 A lost cache of 250-million-year-old fossils from Australia has rewritten part of the story of life after Earth’s worst mass extinction. Instead of a single marine amphibian species, researchers ...
Feb. 24, 2026 Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already ...
Feb. 24, 2026 Deep in the Congo Basin, vast peatlands quietly store enormous amounts of Earth’s carbon — but new research suggests this ancient vault may be leaking. Scientists studying Africa’s largest ...
Feb. 24, 2026 A new 30-year analysis reveals that melting land ice is now the main force behind rising global sea levels. Researchers discovered that oceans rose about 90 millimeters since 1993, with most of the increase coming from added water mass rather than ...
Feb. 22, 2026 Deep in the Arctic north, drained peatlands—once massive carbon vaults built over thousands of years—are quietly leaking greenhouse gases into the atmosphere. But new field research from northern Norway suggests there’s a powerful way to slow ...
Feb. 22, 2026 Flea and tick medications trusted by pet owners worldwide may have an unexpected environmental cost. Scientists found that active ingredients from isoxazoline treatments pass into pet feces, exposing dung-feeding insects to toxic chemicals. These ...
Feb. 18, 2026 Ocean waves are a vast and steady source of renewable energy, but capturing their power efficiently has long frustrated engineers. A researcher at The University of Osaka has now explored a bold new approach: a gyroscopic wave energy converter that ...
Feb. 18, 2026 As the planet warms, many expected ecosystems to change faster and faster. Instead, a massive global study shows that species turnover has slowed by about one-third since the 1970s. Nature’s constant reshuffling appears to be driven more by ...
Feb. 17, 2026 NASA has pulled off a high-flying aurora investigation, launching three rockets into the glowing northern lights over Alaska. One mission targeted mysterious dark patches called black auroras, while ...
Feb. 17, 2026 For years, satellite data suggested that autumn snow cover in the Northern Hemisphere was actually increasing — a surprising twist in a warming world. But a new analysis reveals that this apparent growth was an illusion caused by improving ...
Feb. 16, 2026 Even Antarctica’s toughest native insect can’t escape the reach of plastic pollution. Scientists have discovered that Belgica antarctica — a tiny, rice-sized midge and the southernmost insect on Earth — is already ingesting microplastics in ...
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Feb. 25, 2026 Earth’s magnetic shield is shifting in dramatic ways. New data from ESA’s Swarm satellites show that the South Atlantic Anomaly — a vast weak ...
Feb. 23, 2026 Far beneath the Atlantic Ocean, about 1,000 kilometers off Portugal’s coast, lies a colossal underwater canyon system that dwarfs even the Grand Canyon. Known as the King’s Trough Complex, this ...
Feb. 20, 2026 Scientists at Stanford have unveiled the first-ever global map of rare earthquakes that rumble deep within Earth’s mantle rather than its crust. Long debated and notoriously difficult to confirm, ...
Feb. 18, 2026 Life on Earth may have learned to breathe oxygen long before oxygen filled the skies. MIT researchers traced a key oxygen-processing enzyme back ...
Feb. 17, 2026 When tens of thousands of earthquakes shook Santorini, the cause wasn’t just shifting tectonic plates—it was rising magma. Scientists tracked about 300 million cubic meters of molten rock pushing ...
Feb. 15, 2026 Scientists have developed a powerful new way to trace the journey of water across the planet by reading tiny atomic clues hidden inside it. Slightly heavier versions of hydrogen and oxygen, called ...
Feb. 12, 2026 Long before agriculture, humans were transforming Europe’s wild landscapes. Advanced simulations show that hunting and fire use by Neanderthals and ...
Feb. 12, 2026 A new scientific review challenges the headline-grabbing claim that Yellowstone’s returning wolves triggered one of the strongest trophic cascades on Earth. Researchers found that the reported ...
Feb. 12, 2026 Coral reefs, worth an estimated $9.8 trillion a year to humanity, are in far worse shape than previously realized. A massive international study found that during the 2014–2017 global marine ...
Feb. 12, 2026 Even when Earth was locked in its most extreme deep freeze, the planet’s climate may not have been as silent and still as once believed. New research from ancient Scottish rocks reveals that during ...