Scientists Say: Upwelling
Upwelling (noun, “UP-well-ing”)
This is a process in which one substance rises up through another substance, and then flows outward above it.
In the ocean, for example, surface winds can push warm water away, allowing colder water beneath to rise. The cold water, which is full of nutrients, spreads out on the surface as the warm water moves away. The nutrients then feed plankton and other small organisms, which in turn feed bigger ones such as fish and whales.
Upwelling also happens beneath the surface of the Earth. But there, instead of something cold rising, something hot comes up instead. Really hot. Inside the Earth’s mantle, fiery liquid rock slowly swirls. This hot rock is less dense than the cooler, solid rock above it. As tectonic plates — the moving slabs that make up the Earth’s outer layer — shift around, the liquid rock rises. At the surface, it spreads out, cools and becomes solid. This upwelling adds rocky material to the planet’s crust.
In a sentence
On Jupiter, there is upwelling of clouds in the atmosphere — big stinky clouds of ammonia.
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ammonia A colorless gas with a nasty smell. Ammonia is a compound made from the elements nitrogen and hydrogen. It is used to make food and applied to farm fields as a fertilizer. Secreted by the kidneys, ammonia gives urine its characteristic odor. The chemical also occurs in the atmosphere and throughout the universe.
atmosphere The envelope of gases surrounding Earth or another planet.
carbon dioxide (or CO2) A colorless, odorless gas produced by all animals when the oxygen they inhale reacts with the carbon-rich foods that they’ve eaten. Carbon dioxide also is released when organic matter burns (including fossil fuels like oil or gas). Carbon dioxide acts as a greenhouse gas, trapping heat in Earth’s atmosphere. Plants convert carbon dioxide into oxygen during photosynthesis, the process they use to make their own food.
cloud A plume of molecules or particles, such as water droplets, that move under the action of an outside force, such as wind, radiation or water currents. (in atmospheric science) A mass of airborne water droplets and ice crystals that travel as a plume, usually high in Earth’s atmosphere. Its movement is driven by winds.
Jupiter (in astronomy) The solar system’s largest planet, it has the shortest day length (10 hours). A gas giant, its low density indicates that this planet is composed of light elements, such as hydrogen and helium. This planet also releases more heat than it receives from the sun as gravity compresses its mass (and slowly shrinks the planet).
liquid A material that flows freely but keeps a constant volume, like water or oil.
mantle (in geology) The thick layer of the Earth beneath its outer crust. The mantle is semi-solid and generally divided into an upper and lower mantle.
nutrient A vitamin, mineral, fat, carbohydrate or protein that a plant, animal or other organism requires as part of its food in order to survive.
oxygen A gas that makes up about 21 percent of Earth's atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism).
plankton A small organism that drifts or floats in the sea. Depending on the species, plankton range from microscopic sizes to organisms about the size of a flea. Some are tiny animals. Others are plantlike organisms. Although individual plankton are very small, they form massive colonies, numbering in the billions. The largest animal in the world, the blue whale, lives on plankton.
tectonic plates The gigantic slabs — some spanning thousands of kilometers (or miles) across — that make up Earth’s outer layer.
upwelling A process where a substance rises up through another substance and spreads out on the surface. In the ocean, upwelling along coastlines brings cold, nutrient-rich water from the bottom to the surface. Inside the Earth, there is upwelling from Earth’s middle layer into its outer layer, where it will become part of the tectonic plates.
whale A common, but fairly imprecise, term for a class of large mammals that lives in the ocean. This group includes dolphins and porpoises.