Security

Major US pipeline halts operations after ransomware attack

The operator of a major pipeline system that transports fuel across the East Coast said Saturday it had been victimized by a ransomware attack and had halted all pipeline operations to deal with the threat. The attack is ...

Engineering

Solar-powered desalination unit shows great promise

Despite the vast amount of water on Earth, most of it is nonpotable seawater. Freshwater accounts for only about 2.5% of the total, so much of the world experiences serious water shortages.

Engineering

Freeze! New model to protect ships from ice accretion

Researchers from Skoltech (Russia) and their colleagues from SINTEF (Norway) have developed a mathematical model of freezing water droplets moving in cold air. This model is a part of a joint RFBR-supported Russian-Norway ...

Engineering

Sunlight to solve the world's clean water crisis

Researchers at UniSA have developed a cost-effective technique that could deliver safe drinking water to millions of vulnerable people using cheap, sustainable materials and sunlight.

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Water

Water is a ubiquitous chemical substance, composed of hydrogen and oxygen, that is essential for the survival of many known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71% of the Earth's surface. On Earth, it is found mostly in oceans and other large water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the Earth's water is contained within biological bodies and manufactured products. Other water is trapped in ice caps, glaciers, aquifers, or in lakes, sometimes providing fresh water for life on land.

Water moves continually through a cycle of evaporation or transpiration (evapotranspiration), precipitation, and runoff, usually reaching the sea. Winds carry water vapor over land at the same rate as runoff into the sea. Over land, evaporation and transpiration contribute to the precipitation over land.

Clean, fresh drinking water is essential to human and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and GDP per capita. However, some observers have estimated that by 2025 more than half of the world population will be facing water-based vulnerability. Water plays an important role in the world economy, as it functions as a solvent for a wide variety of chemical substances and facilitates industrial cooling and transportation. Approximately 70 percent of freshwater is consumed by agriculture.

This text uses material from Wikipedia, licensed under CC BY-SA