Disasters at sea trigger ship-safety advances

When one of the world's largest container ships crashed into the bank of the Suez Canal in 2021, a major gateway for global trade became blocked with an estimated $9.6 billion in daily commerce being held up.

Energy & Green Tech

Promising salt batteries for heat storage

Salt batteries can store summer heat to be used in winter, but which salt works best for the purpose? On 19 December, Lian Blijlevens will defend her Ph.D. thesis on her research into salt for heat storage at Radboud University.


Using AI to help dams run smarter

In August 2020, following a period of prolonged drought and intense rainfall, a dam situated near the Seomjin River in Korea experienced overflow during a water release, resulting in damages exceeding 100 billion won (USD ...


Five ways to cool cities as temperatures soar

As Australia heads into an El Niño summer, UNSW's Dr. Negin Nazarian, an expert in urban climate, explains five crucial strategies to keep cities—and people—cooler.

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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