Reference Terms
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Planetary boundary layer
The planetary boundary layer (PBL) is also known as the atmospheric boundary layer (ABL). It is the lowest part of the atmosphere and its behavior is directly influenced by its contact with the ground. It responds to surface forcings in a timescale of an hour or less. In this layer physical quantities such as flow velocity, temperature, moisture etc., display rapid fluctuations (turbulence) and vertical mixing is strong. Physical laws and equations of motions, which govern the planetary boundary layer dynamics and microphysics, are strongly non-linear and considerably influenced by properties of the earth's surface and evolution of the processes in the free atmosphere. Perhaps the most important processes, which are critically dependent on the correct representation of the PBL in the atmosperic models, are turbulent transport of moisture and pollutants. Clouds in the boundary layer influence trade winds, the hydrological cycle, and energy exchange.
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Earth & Climate News
September 16, 2026
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 ...
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Sep. 15, 2026 The Hunga Tonga eruption may have triggered a surprising chemical reaction that destroyed some of the methane released into the atmosphere. Scientists say the discovery could reshape estimates of methane pollution and inspire new methods for slowing ...
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 species more than 50 meters beneath the surface. The ...
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 pose growing environmental risks as they continue ...
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. Scientists traced the difference to volcanic gases ...
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 impacts that persist roughly two and a half times ...
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 disrupted the relationship in the past, while today ...
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 that water-rich pieces of crust periodically sank ...
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 that remain appear unusually small, potentially ...
Sep. 10, 2026 The Mediterranean may seem far removed from the world’s major tsunami zones, but history and modern modeling show that destructive waves can strike the French Riviera with surprisingly little warning. Some tsunamis could reach shore in under 10 ...
Sep. 6, 2026 East Antarctica gained an astonishing 695 billion tons of ice between 2021 and 2023, temporarily slowing Antarctica’s long-term decline. Researchers found that warming thousands of miles away in ...
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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. 9, 2026 Volcanic rocks in Colombia are rewriting the timeline of the collision between Central and South America. Their magnetic signatures show that major ...
Sep. 6, 2026 Indonesia’s dangerous peat fires are surging early in the 2026 fire season as a strengthening El Niño and severe drought dry out wetlands that can burn underground for months. These slow ...
Sep. 4, 2026 Puerto Rico’s normally rainy season has instead brought a severe and fast-growing drought. By August 25, three-quarters of the territory was in at least moderate drought, with extreme drought ...
Sep. 4, 2026 A giant iceberg measuring more than 76 square kilometers broke from Greenland’s Petermann Glacier in August 2026, marking the Arctic’s largest glacier calving event since 2020. The berg later ...
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Sep. 3, 2026 Deep beneath Mars, scientists have found evidence of enormous magmatic systems once thought to require Earth-like plate tectonics. Seismic measurements suggest molten rock repeatedly evolved and ...
Sep. 3, 2026 Elephant Butte Reservoir, New Mexico’s largest reservoir, plunged to just 1.4 percent capacity in July 2026 after years of extreme drought and record early snowmelt. The dramatic decline exposed ...
Sep. 2, 2026 NASA-funded studies suggest Earth’s climate has been influenced by both the Sun’s travels through dense regions of the Milky Way and the violent superflares of its youth. Those events may help ...