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
January 21, 2026
Jan. 21, 2026 A new building material developed by engineers at Worcester Polytechnic Institute could change how the world builds. Made using an enzyme that turns carbon dioxide into solid minerals, the material cures in hours and locks away carbon instead of ...
Jan. 21, 2026 Mountain regions around the world are heating up faster than the lands below them, triggering dramatic shifts in snow, rain, and water supply that could affect over a billion people. A major global review finds that rising temperatures are turning ...
Jan. 19, 2026 Plastic-coated fertilizers used on farms are emerging as a major but hidden source of ocean microplastics. A new study found that only a tiny fraction reaches beaches through rivers, while direct drainage from fields to the sea sends far more ...
Jan. 17, 2026 Tiny plastic particles drifting through the oceans may be quietly weakening one of Earth’s most powerful climate defenses. New research suggests microplastics are disrupting marine life that helps oceans absorb carbon dioxide, while also releasing ...
Jan. 15, 2026 New research shows tropical forests can recover twice as fast after deforestation when their soils contain enough nitrogen. Scientists followed forest regrowth across Central America for decades and found that nitrogen plays a decisive role in how ...
Jan. 15, 2026 In the rapidly disappearing Atlantic Forest, mosquitoes are adapting to a human-dominated landscape. Scientists found that many species now prefer feeding on people rather than the forest’s diverse wildlife. This behavior dramatically raises the ...
Jan. 14, 2026 For thousands of years, wildfires on Alaska’s North Slope were rare. That changed sharply in the 20th century, when warming temperatures dried soils and fueled the spread of shrubs, setting the stage for intense fires. Peat cores and satellite ...
Jan. 14, 2026 Scientists have identified a newly recognized threat lurking beneath the ocean’s surface: sudden episodes of underwater darkness that can last days or even months. Caused by storms, sediment runoff, algae blooms, and murky water, these “marine ...
Jan. 14, 2026 Earth’s oceans reached their highest heat levels on record in 2025, absorbing vast amounts of excess energy from the atmosphere. This steady buildup has accelerated since the 1990s and is now driving stronger storms, heavier rainfall, and rising ...
Jan. 13, 2026 Honey bees can normally keep their hives perfectly climate-controlled, but extreme heat can overwhelm their defenses. During a scorching Arizona summer, researchers found that high temperatures caused damaging temperature fluctuations inside hives, ...
Jan. 13, 2026 Scientists tracking Earth’s water from space discovered that El Niño and La Niña are synchronizing floods and droughts across continents. When these climate cycles intensify, far-apart regions can become unusually wet or dangerously dry at the ...
Jan. 12, 2026 Plastic pollution is not just in oceans and soil. Scientists have now found enormous amounts of microscopic plastic floating through urban air, far exceeding earlier estimates. Road dust and rainfall play a major role in moving these particles ...
Latest Headlines
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Jan. 17, 2026 Scientists are uncovering a hidden and surprisingly complex earthquake zone beneath Northern California by tracking swarms of tiny earthquakes that are far too weak to feel. These faint tremors are ...
Jan. 16, 2026 Hydrogen cyanide, a toxic chemical, may have helped spark the chemistry that led to life. When frozen, it forms crystals with highly reactive surfaces that can drive unusual chemical reactions, even ...
Jan. 12, 2026 Microscopic ocean algae produce a huge share of Earth’s oxygen—but they need iron to do it. New field research shows that when iron is scarce, phytoplankton waste energy and photosynthesis ...
Jan. 10, 2026 Crystals hidden in Australia’s oldest rocks have revealed new clues about how Earth and the Moon formed. The study suggests Earth’s continents didn’t begin growing until hundreds of millions of ...
Jan. 7, 2026 Scientists have discovered that wildfires release far more air-polluting gases than previously estimated. Many of these hidden emissions can transform into fine particles that are dangerous to ...
Jan. 6, 2026 Earthquakes happen daily, sometimes with devastating consequences, yet predicting them remains out of reach. What scientists can do is map the hidden layers beneath the surface that control how ...
Jan. 6, 2026 When a huge earthquake struck near Kamchatka, the SWOT satellite captured an unprecedented, high-resolution view of the resulting tsunami as it ...
Jan. 5, 2026 A meltwater lake that formed in the mid-1990s on Greenland’s 79°N Glacier has been draining in sudden, dramatic bursts through cracks and vertical ice shafts. These events have accelerated in ...
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