why do we need water to survive on earth


Now imagine the air without water. Clouds provide a buffer from the heating power of the sun. Without them it would pour down with no mercy. Dry air would suck out whatever moisture it could find, wherever it could find it, and the noses and soft tissues of any being that lived would shrivel. There would be no sweet scents, since moisture is what conveys smells. The composition of the air would change too. All the methane currently stored in ice, bogs, and the ocean, would be released, thereby increasing the heating effect of the sun. The dust in the air would be blown hither and yon, with nothing to wash it down. Temperatures would swing from extreme to extreme, getting hotter as time went on. The ground, because it would be rock, sand, or dry earth would have nothing in or on it to blunt the heat. The sun, pouring down without mitigation, would beat on the earth and heat it up. Any carbon-based thing would burn up during the day. At night it would freeze.


There would be nothing to soften the effect of volcanoes or to put out fires. There would be no cushioning effect against earthquakes. Any rubbing of tectonic plates against each other would be magnified far beyond what it is now – the trembling would create massive rock slides and crumbling both at the site and in remote areas affected. The surface of the earth would burn and grind itself into dust. Am I exaggerating? Most likely not. The article below talks about earthquakes and the softening effect of water underground.
To understand the importance of Antarctica to the rest of the world we need to look more closely at water and its properties. Water can be found almost anywhere. Water is an essential part of our planet and we need it to survive. В Water covers nearly three-quarters of the Earthвs surface. It is found on the land, under the ground and in the atmosphere. Water can be; fresh (as in lakes, rivers or underground aquifers) or salty (as in the oceans).


В All plants and animals need water. The human body is up to 78% water and to remain hydrated we need to drink water every day. В Water affects how our Earth works and looks. В Did you know that water in the mantle (the layer between Earthвs crust and the core) influences the formation of volcanoes? Weather patterns are affected by water in the oceans, on land and in the air. Water in the form of rain, rivers or glaciers helps to shape our land. How do you think people rely on water? What is different about water? Most substances are denser as a solid than as a liquid. For example, a piece of solid candle wax will sink when placed in molten wax. Water is different. When water freezes into ice, it floats. This is because it is less dense than the surrounding water. В It is very important that ice floats. It means that the surface of rivers, lakes and other water bodies freeze from the top down.


This allows animals and plants to survive in the water beneath the ice. Because ice floats, it stays at the surface so when it is exposed to the Sun and warm temperatures it can melt. Another unusual feature of water is that it can dissolve many things. More substances dissolve in water than in any other liquid although, not everything dissolves in water. В Can you come up with some examples of things which donвt dissolve in water? Water has a thin elastic layer known as surface tension. Have you ever wondered why water droplets stick together to form a dome? Or why some insects can walk on water? The surface of water and other liquids acts like a thin elastic layer в scientists call it surface tension. Water is unusual because it has the greatest surface tension of any liquid at room temperature other than mercury. However, on this field trip you will learn that these properties can change depending on pressure and how pure the water is.

Show More

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button