Water is the only natural substance that can exist as a liquid, gas or solid under everyday conditions.
A stunning computer graphics helps to understand that how much slight water is on the Earth, and just a portion of it is drinking water. The most interesting part of the computer graphics is the little blue water ball, which shows the all water if we collect it from the Earth. The ball demonstrates that only a slight part of the Earth is water, although it covers 71% of our planet. Radius of this water ball is 700 km, which is the nearly half the radios of the Moon.
(Video by Woods Hole Oceangraphic Institution, WHOI)
Water is stored in different parts of the water cycle anywhere. The natural reservoirs – like ocean, atmosphere, cryosphere, litosphere and land – contain more than 1.4 billion km3. For example the ocean contains 97 percent of Earth’s known water supply 1.335 billion km3. Because of its size, the ocean accounts for most of the planet’s precipitation and evaporation. In addition the ocean helps transport nutrients, heat, nutrients around the globe. The precipitation of the ocean is more than three-quarters of global precipitation occurs over the ocean. The evaporation over the ocean is 85 percent of the global total, more than 3 times what occurs over land.
In this picture the blue ball shows the quantity of the fresh water which is drinking water or we can use it for sprinkling or other human activity. Human use of the water is in the agriculture currently accounts for 70 percent of water use worldwide, 22 percent is used by industry, and 8 percent is consumed as drinking water.
North Africa’s largest underground reservoir there is under Libya, Algeria and Chad. A recent study showed that the dry African continent is actually a huge groundwater reservoir. There is hundred times more water in the strata than in the surface. While the African population grows with the water demand together until more than 300 million people don’t get at drinking water. But the scientists says the Africans have to handle the huge drilling with care. Because with hand pumps or low-output water system the drillings won’t be successfully.
Thousands of years of fallen rain-water is exploited in the Syrian desert in Saudi Arabia. They drilling down to the underground lakes, rivers, and create a prosperous plantation, where the annual rainfall is slightly less than 25 millimeters. But for example in the United Arab Emirates or in Jordan in the groundwater level decreases rapidly and the Dead Sea is starting to dry out.
It seems the drinking water will be one of the most important but more and more difficultly accessible natural resource in the following years.
Written by Ilona Kaszanyi