Ever wondered where water comes from? This diagram shows you how the water cycle works.
*The Sun's energy makes water evaporate from rivers, dams and the sea.
*Water also passes into the air when people and animals breathe.
*Water moves through plants, going in through their roots and passes out through their leaves into the air.
*Water molecules rise through the air and join together to form clouds.
* When it falls as rain, water flows back to the sea either over or under the ground.
This diagram is just one of the fascinating things on display at 'ecologic', an exhibition at the Powerhouse Museum in Sydney about creating a sustainable future.
There was a water lab where you could see the different kinds of microbes and bacteria that can live in water. And charts that showed you how much water went in to producing one kilogram of beef (166 litres!). There was also a computer that told you some vital statistics about the planet such as the current world population (6 billion 366 million 211 thousand 120 and rising every second!) and how many days until all the coal on the planet is used up (152,178, almost 417 years).
Burning coal to generate electricity releases carbon dioxide in to the atmosphere. This CO2 builds up and causes global warming which makes countries like Australia even hotter. This means that our precious water supplies are more likely to dry up.Maybe we should stop burning coal and start protecting water? After all, Australia is already the driest inhabited continent on Earth.
What do you think?
