Energy & Green Tech

Japan OKs plan to release Fukushima nuclear plant wastewater

Japan's nuclear regulator on Wednesday approved plans by the operator of the wrecked Fukushima nuclear plant to release its treated radioactive wastewater into the sea next year, saying the outlined methods are safe and risks ...

Energy & Green Tech

Environmentalists oppose more life for California nuke plant

Dozens of environmental and anti-nuclear organizations expressed opposition Tuesday to any attempt to extend the life of California's last operating nuclear power plant, challenging suggestions that its electricity is needed ...

Electronics & Semiconductors

A new wearable technology—for plants

Plants can't speak up when they are thirsty. And visual signs, such as shriveling or browning leaves, don't start until most of their water is gone. To detect water loss earlier, researchers reporting in ACS Applied Materials ...

Energy & Green Tech

Green roofs are worth the cost for urban residents

Plant-covered roofs have become a regular sight in Portland, Oregon. The city is a leader in incorporating green infrastructure for stormwater management, including free street trees, rebates for small residential housing ...

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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