Egg-based coating preserves fresh produce

Eggs that would otherwise be wasted can be used as the base of an inexpensive coating to protect fruits and vegetables, according to Rice University researchers.

Etching the road to a hydrogen economy using plasma jets

Hydrogen is a clean energy source that can be produced by splitting water molecules with light. However, it is currently impossible to achieve this on a large scale. In a recent breakthrough, scientists at Tokyo University ...

Tillage and cover cropping effects on grain production

Incorporating cover crops with tillage reportedly results in increased cover crop decomposition rates and increased mineralization of nutrients from cover crop biomass. Multiple studies have reported mixed results for corn-soybean ...

Small Arctic coastal waterbodies, with big carbon release

Arctic coastal watersheds are some of the most threatened regions on Earth, having undergone substantial climatic, physical and biological changes with the warming of the Earth, scientists have found.

Pinpointing the effects of nanoconfinement on water

Researchers have spent decades studying the properties of water and how they change when there are disruptions to their normal behavior. Research on the topic has a wide range of applications, from biochemical systems to ...

page 1 from 100

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