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.
- New clues about early atmosphere on Mars suggest...on September 21, 2022 at 12:53 pm
New research published in Earth and Planetary Science Letters suggests that Mars was born wet, with a dense atmosphere allowing warm-to-hot oceans for millions of years. To reach this conclusion, researchers developed the first model of the evolution of the Martian atmosphere that links the high temperatures associated with Mars's formation in a molten state through to the formation of the first oceans and atmosphere.
- Climate evolution in the Southeast Indian Ocean...on July 6, 2022 at 4:33 pm
The Miocene, 23 to 5 million years ago, was an important period for the formation of the Antarctic ice sheets (AIS). The mid-latitudes in the southern hemisphere are the area where the westerlies prevailed and the climate there is sensitive to the volume changes of the AIS. Recently, the research team led by Prof. Li Tiegang from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) has reconstructed the Miocene climatic evolution in the southeast Indian Ocean. This history […]
- Modeling electrolyte transport in water-rich...on June 22, 2022 at 2:51 pm
Oceans on water-rich exoplanets may be enriched with electrolytes, including salts such as sodium chloride, suggests a modeling study published in Nature Communications. The research proposes electrolytes can be transported from the rocky core of these planets and may have implications for the potential habitability of these ocean worlds.
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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.
Water News -- ScienceDaily Learn about Earth's water resources. Read current research on the water cycle, water pollution, groundwater depletion and lake protection.
- La Niña winters could keep on comingon October 3, 2022 at 7:21 pm
Forecasters are predicting a 'three-peat La Niña' this year. A recent study of ocean temperature patterns suggests that climate change could, in the short term, be favoring La Niñas. A La Niña winter tends to be cooler and wetter in the Pacific Northwest and hotter and drier in the U.S. Southwest. Other worldwide effects include drier conditions in East Africa, and rainier weather in Australia, Indonesia, Malaysia and the Philippines.
- Success in synthesizing biodegradable plastic...on October 3, 2022 at 3:02 pm
Scientists have achieved an 80% conversion yield of a biodegradable plastic material from acetone and CO2, tackling the plastic waste crisis while moving toward carbon neutrality. Scientists have successfully synthesized 3-hydroxybutyrate, a raw material for poly-3-hydroxybutyrate (PHB) -- a strong, water-insoluble, biodegradable plastic used for packaging materials -- from acetone and CO2. With a visible light-driven catalytic system utilizing sunlight and two biocatalysts, the researchers […]
- Lake sediments show decades of coal ash...on October 3, 2022 at 1:05 pm
An analysis of sediments from five North Carolina lakes near coal-burning power plants has found that coal ash pollution of surface waters has been more persistent and widespread than was previously known. The study authors warn that this is likely a problem for every surface water body near a coal plant and will only grow worse as climate change brings more extreme weather events and flooding.
- Exquisitely thin membranes can slash energy spent...on September 30, 2022 at 12:40 am
Scientists have created a new type of nanomembrane that presents a less energy intensive way to fractionate hydrocarbons from crude oil. The global production of crude oil is currently around 80 million barrels per day. Hydrocarbons extracted from crude oil are the main ingredients for manufacturing fossil fuels, plastics, and polymers. The process by which they are extracted is extremely energy intensive. Membrane technology that can separate the molecules in crude oil by their different sizes […]
- Observations confirm model predictions of...on September 30, 2022 at 12:40 am
Rising sea levels from melting glaciers and ice sheets pose an increasing threat to coastal communities worldwide. A new analysis of high-resolution satellite observations takes a major step forward in assessing this risk by confirming theoretical predictions and computational models of sea-level changes used to forecast climate-change-driven impacts.
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