Selasa, 03 September 2013

World of Water—Enough for All?

Berbuat dan Berhemat untuk Air.


Unequal distribution, pollution, and competition limit access to fresh water

It evaporates from the oceans, falls on the land, runs into the rivers, and flows back to the sea—water, a seemingly limitless resource. But only 2.5 percent of Earth’s water is fresh water, and most of that is frozen in polar ice and snow. Of the available fresh water, only 0.6 percent is usable. Climate change would redistribute where and when water is available, rising sea levels could turn coastal fresh water brackish.

The hydrologic cycle yields a contant amount of water, but the quality is deteorirating while the human population continues to grow. Some 80 countries already report shortages. More than a billion people do not have safe drinking water, and 25,000 die every day from water-related diseases. As water shortfalls intensify, so will competition—among countries strung along a river, for example—and violence may result.

Everyone needs at least 13 gallons (.05 cubic meter) of clean water a day for drinking, cooking, and sanitation, says water specialist Peter H. Gleick. Yet a sixth of the world’s people must make do with less than that. Dense populations and unchecked pollution create scarcity even in Africa and Asia’s wet regions.

Some water can be used again, though often it must be cleaned first. But most water for irrigation, the biggest single use, cannot be recylced. In the U.S. about 30 percent of all irrigation water is groundwater pumped from the High Plains aquifer, now drawn down so far that it will take thousands of years to recharge naturally.

Where is the water going...

Agriculture (70%)
About 17 percent of the world’s cropland is irrigated, producing 40 percent of all food grown and using some 600 cubic miles (2,500 cubic kilometers) of water a year. Cotton and rice soak up huge amounts. Forty percent of all again goes to feed livestock for meat—a food that is highly water intensive to produce.

Industry (20%)
Technological advances can reduce water needs in some industries. In the 1930s making a ton of steel required 60 to 100 tons of water. Now less than 6 tons of water does the job. Producing a ton of aluminium—a substitute for steel—uses only 1.5 tons of water, water for cooling power plants is often recycled.

Domestic (10%)
Water use for sanitation, cooking, and drinking in homes and public buildings is decreasing in some developed countries. Before 1990 most U.S. toilets used about 6 gallons per flush. Toilets sold after 1994 use only 1.6 gallons. Newer front-loading washing machines use 39 percents less water than top loader.

...and where is the pollution comming from?

Agriculture
Fertilizers, pesticides, herbicides, animal waste, salts from evaporated irrigation water, and silt from deforestation flow into ground and surface water.

Industry
Manufacturing and mining pollute water with toxic chemicals and heavy metals. Power plant emissions create acid rain, which contaminates surface water.

Domestic
Untreated sewage increasingly taints urban rivers in developing countries. Salt water seeps into coastal aquifers depleted by overuse.

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Musim kemarau telah tiba. Beberapa daerah di Jawa Tengah dan beberapa daerah di Indonesia mengalami gagal panen. Memaksa para petani untuk mengeluarkan dana tambahan, supaya lahan pertaniannya dapat terairi kembali. Sedangkan, disatu sisi saudara kita yang berada di timur Indonesia memiliki sumber air melimpah. Namun pada kenyataannya, pemaanfaatan air bersih untuk konsumsi air minum dan mandi di sana masih kurang dari kata sehat.

Kita yang berada di perkotaan pun juga tak dapat dikatakan tercukupi untuk sumber air bersih. Melalui kajian kesehatan setempat, sumber air yang dapat kita akses melalui perusahaan daerah air minum yang tersalurkan langsung kerumah-rumah penduduk juga belum dapat dikatakan higenis.

Mari kita  berhemat dan berbuat untuk air. Bukan hanya untuk kita saja, melainkan untuk anak cucu kita. Seperti ajakan Slank melalui pendekatan bermusiknya berikut ini:

Ketika sungai-sungai kotor
Maka air terkontaminasi
Ketika air tanah berlimbah
Jangan cuma diam dan menunggu
Berbuatlah untuk air

Ketika sumur-sumur mengering
Ketika bumi makin memanas
Sumber kehidupan, gak ada lagi
Jangan Cuma diam dan menunggu

Hey, berhematlah, berhematlah
Berhematlah untuk air

Krisis, krisis, air, air, krisis
Krisis, krisis, air, air, krisis

Ketika kesegaran hilang
Ketika kehausan datang
Ketika kematian menjelang
Jangan Cuma diam dan menunggu

Berlarilah, berlarilah, berlarilah, berlarilah
Berlarilah untuk air

Krisis, krisis, air, air, krisis
Krisis, krisis, air, air, krisis

(Krisis Air—Slank)

Get Involved:

Tour the Columbia River and learn more about the conservation issues facing this majestic waterway: www.nationalgeographic.com/earthpulse/columbia

The World’s Water
www.worldwater.org

Water Sciene for Schools

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