Health

Avoid ice baths for repairing or building muscle after exercise

Successful athletes such as Andy Murray and Jessica Ennis-Hill are known for using ice baths after exercise, however new research has thrown cold water on this strategy. New research suggests that ice baths aren't helpful ...

Health

Play it safe with holiday foods

(HealthDay)—When preparing the Thanksgiving feast this week, don't forget food safety, a medical expert says.

Medications

Is opioid treatment available to those who need it most?

The U.S. opioid epidemic is still raging—it's particularly pronounced in low-income areas and in those where people lack access to health care services, which includes cities in Michigan and across the Rust Belt. But the ...

Health

Why hand-washing beats hand sanitizers

Proper hand-washing with soap and water is one of the best ways to protect yourself during the cold and flu season, an expert says.

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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