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Water Cycle
The water cycle on earth is an interesting system of water moving from the earth, to the air and back to earth. The system is one way water is redistributed around the planet, how it's cleaned to give us good water quality, and how it cleans the air. But with the amount of pollution we have today, the water cycle has also become part of the pollution cycle where pollutants are moved around the earth, appearing far from the pollution source.
Understanding the water cycle is essential to understanding water pollution. The water cycle helps you to understand how your water comes to be and how pollutants may possibly get into those water sources. The water cycle helps to show you just how connected everything in the environment is and why it is so important that you give special attention to how you impact the environment. You will be surprised by how cyclical the water cycle itself is and how much impact you can make upon the water supply in your area.
The water that you drink is thousands and possibly, millions, of years old. All the water that we use and drink has been used or drunk before. This may sound gross, but it is just part of the water cycle. Dinosaurs may have drunk the same water that you are drinking today -- isn't that wild to think about? This continuous cycle of water is what the water cycle is all about. There are many different parts of the water cycle and this is why it works so well. Here is a summary of how the water cycle works.
There isn't a beginning or ending to the water cycle, so let's begin with the ocean. The oceans make up the majority of water is concentrated on the Earth. It's essentially the source of our drinking water. The sun heats the ocean, which causes the water to evaporate into the air. The air moves across the oceans and then condenses the water vapors into clouds. When the clouds meet cool air, precipitation in the form of rain, snow, sleet, or hail falls onto the earth. The frozen parts of the world may store this water for thousands of years in polar ice caps and glaciers.
Surface runoff is a very important part of the water cycle. The water that falls onto the earth flows into water sources like lakes, streams, and rivers where gravity pulls some of it back to the oceans. This water may also filter through the ground to replenish aquifers, freshwater stores deep in the surface of the earth. Aquifers have been a great source of clean, drinkable water, but it takes so long for water to filter to the aquifers that our rate of consumption, scientists figure we are depleting the aquifers, not replenishing them. Some of these aquifers have small openings, which causes the water to flow under the ground back into the oceans or the water may emerge as freshwater springs. And the cycle continues with the sun evaporating water where it can form clouds that release water back to the earth.
This water cycle summary is very basic, but it gives you an idea of how the water cycle on Earth works. You can see where pollution can get into the water sources -- through rain, when pollutants get into the air through smog, or through runoff, when pollutants, like fertilizers and herbicides, are used. Pollution does not have to be directly put into water sources -- it can get there through the water cycle, which is why it is important to evaluate everything that you do.
The water cycle helps to explain how some types of pollution get into water sources. By knowing more about the water cycle, you will understand why it is so important that you be careful with using chemicals, including herbicides, fertilizers, etc. By making changes to more environmental friendly products, you can make a big impact upon the water sources all over the world, due to the water cycle.
