Engineering

Electronic eye: Technology for breakdowns prevention

Detecting deformations and the wear-out rate of underground water mains is one of the functions of the measuring optical device created by the scientists of Ural Federal University in collaboration with D-TEST Optical Measurement ...

Robotics

A tiny soft robot that mimics jellyfish

A team of researchers at the Max Planck Institute for Intelligent Systems has developed a soft robot that effectively mimics a tiny jellyfish. In their paper published in the journal Nature Communications, the group describes ...

Energy & Green Tech

Ethane storage seen as key to revitalization of Appalachia

Plans are underway in Appalachia to create two underground facilities to store ethane, a byproduct of natural gas drilling seen as integral to revitalizing a region still struggling from the loss of industrial and manufacturing ...

Robotics

An army of microrobots can wipe out dental plaque

visit to the dentist typically involves time-consuming and sometimes unpleasant scraping with mechanical tools to remove plaque from teeth. What if, instead, a dentist could deploy a small army of tiny robots to precisely ...

Other

NOAA satellites helped rescue 340 people in 2018

The pilot of the rowboat Alba had a noble goal – to raise awareness and funds for the Scottish Association for Mental Health. And he was going to row 3,400 nautical miles, from Norfolk, Va., to his home in Scotland, to ...

Robotics

Researchers create 3-D-printed soft mesh robots

Researchers at North Carolina State University have created 3-D-printed flexible mesh structures that can be controlled with applied magnetic fields while floating on water. The structures can grab small objects and carry ...

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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