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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
September 22, 2026
Sep. 22, 2026 Researchers have created a concrete mixture that is both stronger and capable of absorbing carbon dioxide. The best formula, combining zeolite with bamboo biochar, boosted compressive strength by 7.48% and tensile strength by 15% compared with ...
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Sep. 21, 2026 A large Amazon study suggests the most powerful conservation move may be protecting the forests that are already standing. Preventing damage from wildfires and logging delivered the greatest ...
Sep. 20, 2026 Nearly three decades of Hurricane Hunter data reveal four features that can help a tilted tropical cyclone straighten its circulation and become capable of intensifying. The findings could give ...
Sep. 19, 2026 A deep-sea microbe uses an exceptionally heat-resistant enzyme to turn atmospheric nitrogen into ammonia at temperatures that would destroy most proteins. Its unusual structure and a newly observed reaction state may reveal an ancient, shared ...
Sep. 18, 2026 Scientists are looking to diatoms, sea sponges, and plants for a cleaner way to recover rare earth elements and other valuable minerals hidden inside coal ash, red mud, and mine tailings. The bio-inspired approach could turn massive industrial waste ...
Sep. 17, 2026 Anak Krakatau erupted for more than 24 hours in early September, sending volcanic ash up to 50,000 feet into the atmosphere. The ash cloud shut down eight airports, disrupted nearly 3,000 flights, and affected air quality as far away as Jakarta. ...
Sep. 17, 2026 Arctic sea ice may move in unexpected ways because individual ice floes are constantly colliding and transferring energy. Researchers found that this simple process can explain several long-standing mysteries about how quickly the ice moves and ...
Sep. 16, 2026 Scientists have developed a solar-powered desalination system that turns seawater into fresh water while removing nearly all of the leftover salt as a solid instead of producing harmful brine. The self-cleaning technology could also recover valuable ...
Sep. 16, 2026 U.S. irrigation produces some greenhouse gas emissions, but new research suggests it prevents vastly more by allowing farmers to grow more food on less land. Without irrigation, replacing lost crop yields could require converting natural ecosystems ...
Latest Headlines
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Sep. 16, 2026 A new study suggests Earth formed almost entirely from material in the inner Solar System, challenging the idea that water-rich material from beyond ...
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Sep. 14, 2026 More than 60 years after surveys suggested a deep coral reef off Benin was probably dead, scientists have found it alive. Cameras revealed healthy-looking coral patches supporting multiple fish ...
Sep. 14, 2026 A World War I submarine wreck off Denmark is leaking TNT into the surrounding water, seabed, and marine life more than a century after it sank. Scientists warn that thousands of similar wrecks could ...
Sep. 13, 2026 Mount Etna’s ancient eruptions followed radically different paths, with some magma lingering near the surface for weeks while other magma raced upward from nearly 30 kilometers deep in just hours. ...
Sep. 13, 2026 Scientists have found that Arctic cyclones become especially destructive when several strike one after another. These storm clusters cause about twice as much sea ice loss as isolated cyclones, with ...
Sep. 13, 2026 The Indian and Pacific oceans have been climatically linked for centuries, but scientists say that connection is now breaking down in an exceptional way. Ancient climate records suggest volcanoes ...
Sep. 12, 2026 Ancient rocks from Western Australia suggest water was reaching deep inside Earth more than three billion years ago, long before modern plate tectonics may have fully developed. Researchers propose ...
Sep. 11, 2026 Britain’s wasps have become mysteriously scarce this summer, and scientists suspect an unusual combination of temperature swings, heatwaves, and food shortages may be responsible. Even the wasps ...
Sep. 10, 2026 Scientists have used DNA from living descendants to identify four more members of the doomed Franklin expedition, including Harry Peglar, whose identity had remained uncertain for 166 years. The ...