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Reference Terms
from Wikipedia, the free encyclopedia

Humidity

Humidity is the concentration of water vapor in the air. The concentration can be expressed as absolute humidity, specific humidity, or relative humidity. Relative humidity is the most frequently encountered measurement of humidity because it is regularly used in weather forecasts. It’s an important part of weather reports because it indicates the likelihood of precipitation, dew, or fog. Higher relative humidity also makes it feel hotter outside in the summer because it reduces the effectiveness of sweating to cool the body by preventing the evaporation of perspiration from the skin. This effect is calculated in a heat index table.

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Earth & Climate News

August 7, 2026

Glyphosate was long thought to be safe for honeybees because they lack the enzyme the chemical targets in weeds. However, researchers found that exposed bees foraged 13 percent less after only three days and showed changes in brain chemicals linked ...
Ancient seafloor sediments have revealed a surprising twist in how the Atlantic’s massive circulation system works. During a cold period about 3.4 million years ago, the flow of warm, salty water ...
Historic wildfires scorched huge areas of Spain and France, with one Spanish blaze burning an area about the size of New York City and a French fire generating a rare, towering fire cloud. A dangerous combination of lush winter growth, severe heat, ...
Animal bones preserved in South Australia’s underwater caves reveal distinctive clues shaped by darkness, algae, bacteria, and other environmental conditions. The findings give scientists a powerful new way to reconstruct how ancient megafauna ...
Thawing Arctic permafrost is releasing ancient carbon into the ocean, raising fears that microbes could turn it into greenhouse gases and accelerate climate change. But sediment cores collected near ...
An AI analysis of 1.2 million satellite images shows that floating algae blooms are spreading across the global ocean. The rapid growth of massive seaweed mats could reshape marine habitats while bringing foul-smelling decay, ecological damage, and ...
Coastal communities are facing a hidden threat that is making rising seas far more dangerous: the land beneath them is sinking. New research shows that people in densely populated coastal regions experience an average relative sea-level rise of ...
Global warming appears to have shifted into a faster gear. After removing the effects of El Niño, volcanic eruptions, and solar cycles, researchers found that the planet has warmed at roughly 0.35°C per decade over the past ten years, compared ...
Scientists discovered unusually high water-vapor supersaturation inside deep tropical clouds, creating conditions in which tiny aerosol particles could intensify storm updrafts. The finding suggests earlier studies may have missed the effect because ...
A new chemical process can transform three of the most common plastics into high-purity hydrogen without sorting them first. The technique operates at much lower temperatures than traditional ...
Songbirds appear to have evolved through rare explosions of change separated by long periods of slower development. Many of those bursts lined up with major climate shifts, suggesting that environmental upheaval can reshape life in powerful ...
Bumblebees naturally have short lives, but extreme heat and human activity are making survival harder. Pesticides can poison bees or destroy the flowers they depend on, while habitat loss leaves them with fewer safe places to live and feed. ...

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