New study: Thick sea-ice warms Greenland fjords

A new study led by Stockholm University Assistant Professor Christian Stranne shows that thick sea ice outside the fjords can actually increase the sensitivity of Greenlandic fjords to warming. Stranne and a team of researchers ...

Exploration of ocean currents beneath the 'Doomsday Glacier'

For the first time, researchers have been able to obtain data from underneath Thwaites Glacier, also known as the "Doomsday Glacier." They find that the supply of warm water to the glacier is larger than previously thought, ...

Better solutions for making hydrogen may lie just at the surface

A clean energy future propelled by hydrogen fuel depends on figuring out how to reliably and efficiently split water. That's because, even though hydrogen is abundant, it must be derived from another substance that contains ...

Mountain growth influences greenhouse effect

Taiwan is an island of extremes: severe earthquakes and typhoons repeatedly strike the region and change the landscape, sometimes catastrophically. This makes Taiwan a fantastic laboratory for geosciences. Erosion processes, ...

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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.

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