Water (main)

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From the earliest life forms to life on earth as we know it today, water has been the one essential constant . Covering roughly seventy percent of the earth’s surface, only a mere fraction is available as freshwater and of that, an even smaller proportion is available for human use and we are only just beginning to truly understand the nature of this most precious and limited resource. In addition to its life sustaining role, water is also one of the most destructive forces on earth, carving breath taking gorges and valleys, yet disasters related to water are responsible for large scale loss of life as well. In its different forms water supports ocean life, retains precious atmospheric samples dating back thousands of years, is a muse for writers, artists, and sculptors, as it tenuously supports a human population of six billion and growing.

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Haiti Cholera Outbreak (FAQ) The outbreak of cholera was confirmed in Haiti on October 21, 2010. Although we can’t be certain,... More »

Hydrologic cycle (Water) The hydrologic cycle is a conceptual model that describes the storage and movement of water between the biosphere, atmosphere, lithosphere, and the hydrosphere (see Figure 1).... More »

Bicilavadora: Green Washing Machine Bicilavadora Challenge In Peru, many women earn their living by washing clothes by hand, which limits the amount of laundry they can do each day. How does it... More »

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Agriculture II (Water) Humans began to cultivate food crops about 10,000 years ago. Prior to that time, hunter-gatherers secured their food as they traveled in the nearby environment. When they... More »

Infiltration and soil water storage Infiltration refers to the movement of water into the soil layer. The rate of this movement is called the infiltration rate. If rainfall intensity is greater than the... More »

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Arctic Ocean (Water) Ice is the dominant feature of Arctic marine ecosystems. It continuously sculpts the coastal landscape and acts as a major limiting factor to all biological activity. Two... More »

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Ice sheet (Water) An ice sheet is the contiguous assemblage of glaciers of sizeable extent; there are presently a number of well defined ice sheets, the two largest being the Antarctic Ice Sheet... More »

Hypersaline lake (Water) A hypersaline lake is a lacustrine body of water which exhibits levels of dissolved salts that exceed seawater (e.g. greater than 35 grams per litre). A large percentage of the... More »

Kunene River (Water) The Kunene River (also Cunene River) is a river is southwestern Africa, 1050 kilometers long, with its watershed primarily within the nation of Angola but also drawing... More »

Spratly Islands (Water)</span> The Spratly Islands consist of more than 150 small islands or reefs scattered over a sea area of nearly 360,000 square kilometres in the South China Sea, about two-thirds of the way from southern Vietnam to the southern Philippines. The closest countries to the Spratly Islands are Malaysia, Vietnam, Brunei and the Philippines. Abundant in marine biodiversity, the Spratly Islands lie in rich fishing grounds and potential gas and oil deposits. (See Energy profile of South China Sea) These islands are strategically located near several primary strategic shipping lanes in the central South China Sea. There are no indigenous inhabitants. But there are scattered garrisons occupied by military personnel of several claimant states, notably the Philippines. They are claimed in their entirety by Taiwan, Vietnam and China, while portions are claimed by Malaysia and... More »

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Malaysia- FAO's Information System on Water and Agriculture Malaysia is situated in southeast Asia. It consists of two regions: peninsular Malaysia in the west lying between Thailand and Singapore, and the states of Sabah and Sarawak located in the east on the island of Borneo. The two regions are separated by the South China Sea. The total land area of the country is 328550km². Malaysia is a federal country, divided into 13states plus the federal territories of Kuala Lumpur and Labuan Island.. The Food and Agriculture Organization of the United Nations (FAO) leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and debate policy. FAO is also a source of knowledge and information. In peninsular Malaysia, a mountainous spine known as Banjaran Titiwangsa sepa-rates the east of the... More »

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Stream (Water) Streams alter the Earth's landscape through the movement of water and sediment (Figure 1). Streams are powerful erosive agents moving material from their bed and banks. In mountainous regions, stream erosion often produces deep channels and canyons. Streams also deposit vast amounts of sediment on the terrestrial landscape and within lakes and ocean basins. Geomorphologists often view streams as systems. The stream system, like almost all environmental systems, is open to both inputs and outputs of various types of materials. Water enters the stream system by direct precipitation in the channel, from runoff, throughflow, and by groundwater flow. The movement of water into a stream also carries with it dissolved and solid materials eroded from the surrounding landscape, stream banks, and the stream bed. Sediments carried by streams to lower elevations are occasionally... More »

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Hydroelectricity (Water) Hydroelectricity is electricity generated by converting the kinetic energy of falling or flowing water. It is considered the most widely installed form of renewable energy, although most large dams have a finite lifetime unless dredging of silt is periodically conducted. Hydroelectricity has and has a considerably lower output level of the greenhouse gas carbon dioxide than fossil fuel powered energy plants, and less life cycle greenhouse gas impact than solar power. Furthermore, the ecological impacts of hydropower is arguably greater than any form of energy production, due to the large footprint of biological impact of reservoirs and other needed developed areas. Worldwide, an installed capacity of 777 Gigawatts was catalogued in the year 2006, sufficient to supply one fifth of the world power supply. Since most of the prime locations for hydroelectric power have been tapped, the... More »

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Water pollution (Water) Water pollution is the contamination of natural water bodies by chemical, physical, radioactive or pathogenic microbial substances. Adverse alteration of water quality presently produces large scale illness and deaths, accounting for approximately 50 million deaths per year worldwide, most of these deaths occurring in Africa and Asia. In China, for example, about 75 percent of the population (or 1.1 billion people) are without access to unpolluted drinking water, according to China's own standards.[1] Widespread consequences of water pollution upon ecosystems include species mortality, biodiversity reduction and loss of ecosystem services. Some consider that water pollution may occur from natural causes such as sedimentation from severe rainfall events; however, natural causes, including volcanic eruptions and algae blooms from natural causes constitute a minute amount of the... More »