water : the liquid that descends from the clouds as rain, forms streams, lakes, and seas, and is a major constituent of all living matter and that when pure is an odorless, tasteless, very slightly compressible liquid oxide of hydrogen H2O which appears bluish in thick layers, freezes at 0° C and boils at 100° C, has a maximum density at 4° C and a high specific heat, is feebly ionized to hydrogen and hydroxyl ions, and is a poor conductor of electricity and a good solvent — Webster
Water is a transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth’s streams, lakes, and oceans, and the fluids of most living organisms. It is vital for all known forms of life, even though it provides no calories or organic nutrients. Its chemical formula is H2O, meaning that each of its molecules contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is the name of the liquid state of H2O at standard ambient temperature and pressure. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds are formed from suspended droplets of water and ice, its solid state. When finely divided, crystalline ice may precipitate in the form of snow. The gaseous state of water is steam or water vapor. Water moves continually through the water cycle of evaporation, transpiration (evapotranspiration), condensation, precipitation, and runoff, usually reaching the sea.
Water covers 71% of the Earth’s surface, mostly in seas and oceans. Small portions of water occur as groundwater (1.7%), in the glaciers and the ice caps of Antarctica and Greenland (1.7%), and in the air as vapor, clouds (formed of ice and liquid water suspended in air), and precipitation (0.001%).
Water plays an important role in the world economy. Approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of long-distance trade of commodities (such as oil and natural gas) and manufactured products is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving. — Wikipedia
Hydrosphere is the combined mass of water found on, under, and above the surface of a planet, minor planet or natural satellite. Although the hydrosphere has been around for longer than 4 billion years, it continues to change in size. This is caused by the seafloor spreading and the continental drift, which rearranges the land and ocean.
It has been estimated that there are 1,386 million cubic kilometers of water on Earth. This includes water in liquid and frozen forms in groundwater, oceans, lakes and streams. Saltwater accounts for 97.5% of this amount. Vapor is another form water is in, caused by a rapid increase in particles transferred by heat. Fresh water accounts for only 2.5%. Of this fresh water, 68.9% is in the form of ice and snow cover in the Arctic, the Antarctic, and mountain glaciers. 30.8% is in the form of fresh groundwater. Only 0.3% of the fresh water on Earth is in easily accessible lakes, reservoirs and river systems. The total mass of the Earth’s hydrosphere is about 1.4 × 1018 tonnes, which is about 0.023% of Earth’s total mass. About 20 × 1012 tonnes of this is in Earth’s atmosphere (for practical purposes, 1 cubic meter of water weighs one tonne). Approximately 71% of Earth’s surface, an area of some 361 million square kilometers (139.5 million square miles), is covered by ocean. The average salinity of Earth’s oceans is about 35 grams of salt per kilogram of sea water (3.5%). — Wikipedia
Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the water cycle, water resources and environmental watershed sustainability. A practitioner of hydrology is a hydrologist, working within the fields of earth or environmental science, physical geography, geology or civil and environmental engineering. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management. Hydrology subdivides into surface water hydrology, groundwater hydrology (hydrogeology), and marine hydrology. Domains of hydrology include hydrometeorology, surface hydrology, hydrogeology, drainage-basin management and water quality, where water plays the central role. — Wikipedia
Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.
- Can a planet have a mind of its own?on February 16, 2022 at 7:56 pm
The collective activity of life—all of the microbes, plants, and animals—have changed planet Earth.
- One student's mission to protect the world's most...on August 25, 2021 at 8:16 pm
Hooman Chamani, a Ph.D. candidate in Ottawa, is motivated by one thing: To address the global water crisis in an environmentally friendly manner. It may sound simple, but until recently, it was not.
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Every day—up to thirty times a day, in fact—one of Mark Mason's employees at Nature's Reward Farms in Monterey County, California brings him the results of a soil test for discussion.
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- China's EarthLab begins trials as country's first...on June 23, 2021 at 3:28 pm
The Earth is a sphere, and it comprises other spheres: atmosphere, hydrosphere, cryosphere, lithosphere and biosphere—in short, all of the cycles that interact to influence Earth's weather and climate. Now, to better research how the spheres interact and impact the planet, China is launching EarthLab in Beijing. On June 23, after EarthLab's opening ceremony, researchers will begin trials to demonstrate the facility's ability to integrate simulations and observations to more accurately project […]
Water News -- ScienceDaily Learn about Earth's water resources. Read current research on the water cycle, water pollution, groundwater depletion and lake protection.
- Watching corals breathe: Simultaneously measuring...on May 23, 2022 at 3:55 pm
An international research team has developed tiny particles that measure the oxygen concentration in their surroundings. In this way, they can track fluid flow and oxygen content at the same time -- exciting prospects for many fields of research, from biology to physics.
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A new energy-efficient way to produce hydrogen gas from ethanol and water has the potential to make clean hydrogen fuel a more viable alternative for gasoline to power cars.
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It is widely understood that thawing permafrost can lead to significant amounts of methane being released. However, new research shows that in some areas, this release of methane could be a tenth of the amount predicted from a thaw. A crucial, yet an open question is how much precipitation the future will bring.
- Deciphering the biosynthetic gene cluster for...on May 20, 2022 at 6:47 pm
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- PFAS chemicals do not last foreveron May 20, 2022 at 6:47 pm
Once dubbed 'forever chemicals,' per-and polyfluoroalkyl substances, or PFAS, might be in the market for a new nickname. Adding iodide to a water treatment reactor that uses ultraviolet (UV) light and sulfite destroys up to 90% of carbon-fluorine atoms in PFAS forever chemicals in just a few hours, reports a new study led by environmental engineers. The addition of iodide accelerates the speed of the reaction up to four times, saving energy and chemicals.
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