Natural resources (economically referred to as lan

Water cycle is one of the most interesting environmental cycles to learn about. One can always experiment with simple projects on water cycle and observe this cycle practically. This article will provide you with an explanation of the water cycle for kids with the different stages of the water cycle and some interesting projects to perform and observe the water cycle.

Atmospheric air comprises certain elements in a specific ratio. According to NASA (National Aeronautics and Space Administration), 99.998 percent of the Earth's atmosphere is made up of four compounds. These major components are nitrogen, oxygen, argon and carbon dioxide. Another major component of the Earth's atmosphere is water vapor, which is not included in studying the dry composition of air. In short, air composition without water vapor is called dry air. The percentage of water vapor may range from 1-5 percent. Substances present in the air, other than these five main components are referred to as trace elements. Read more on planet earth facts.

Composition of Air

The composition of air in the atmosphere remains nearly unchanged till an altitude of 10 meter. Dust particles also make up the atmospheric air to some extent. Any major alteration in the percentage composition of air is associated with changes in the global climate. The following table represents the components of atmospheric air with their symbol, molecular weight and percentage ratio by volume:

Table for Composition of Air

Component	Element Symbol	Molecular Weight	Percent by Volume
Nitrogen	N2	28.01	78.084%
Oxygen	O2	32.00	20.947%
Argon	Ar	39.95	0.934%
Carbon Dioxide	CO2	44.01	0.033%
Neon	Ne	20.18	0.001818%
Helium	He	4.00	0.000524%
Krypton	Kr	83.80	0.000114%
Methane	CH4	16.04246	0.0002%
Hydrogen	H2	2.02	0.00005%
Nitrous Oxide	N2O	44.01288	0.00003%
Xenon	Xe	131.30	0.0000087%
Ozone	O3	47.9982	0.000007%
Nitrogen dioxide	NO2	46.005	0.000002%
Iodine	I2	253.8	0.000001%
Carbon monoxide	CO	28.0101	Trace
Ammonia	NH3	17.03	Trace

For easy understanding of air composition at the first glance, you can also refer to a pie chart for the composition of air which you will find plentiful on-line. The major role played by each of these components is different. For example, nitrogen is the most important plant nutrient, while oxygen is responsible for respiration and combustion. Nitrogen is also important for diluting the oxygen concentration and stabilizing the atmosphere.

Air Components: Quick Facts

Concentrations of greenhouse gases in the air is important for studying the global climatic change. The raising level of greenhouse gases like carbon dioxide and methane in the atmosphere is the major cause for global warming. It is because of the increasing greenhouse gases that raises the concern of melting of glaciers and elevation in the global temperature.

The level of aerosols (smoke, smog, pollutants, etc.) suspended in the air is a determining factor for the Earth's energy budget. Atmospheric aerosols change the heat retention by the Earth's surface and also, cloud formation. Overall, aerosols are another factor for changing the energy budget of the Earth. Studies are going on to determine the effects of aerosols in regional and global climatic changes.

The water vapor holding capacity of air varies with temperature. The higher the temperature of air, the lesser is the content of water vapor. This is the reason why, water vapor concentration differs from one place to another. Air in areas near to the sea contain higher concentration of water vapor, while air in desert environments contain low levels of moisture.

While studying respiration, generally we come across statements like breathing in oxygen and releasing carbon dioxide. It is not exactly the case; the air that we breathe out (exhaled air) is not entirely carbon dioxide. A maximum percentage of it makes up moisture, 4.4 percent carbon dioxide, 14 percent oxygen and other elements.

With the rising issues of environmental issues or most precisely, air pollution, studying the composition of air has become a topic of common interest. Scientific studies opine that concentration of oxygen less than 19.5 percent in the atmosphere can result in various physiological changes in all the life forms. And an atmospheric condition with oxygen amount below 16 percent is life threatening.

Choose water-efficient products and test your WaterSense - A family of four uses 400 gallons of water every day. EPA's WaterSense program helps conserve water for future generations by providing information on products and programs that save water without sacrificing performance.

More steps you can take:

• Don't let the water run while shaving or brushing teeth.
• Take short showers instead of tub baths.
• Keep drinking water in the refrigerator instead of letting the faucet run until the water is cool.
• Scrape, rather than rinse, dishes before loading into the dishwasher; wash only full loads.
• Wash only full loads of laundry or use the appropriate water level or load size selection on the washing machine.
• Buy high-efficient plumbing fixtures & appliances.
• Repair all leaks (a leaky toilet can waste 200 gallons a day).
• Water the lawn or garden during the coolest part of the day (early morning is best).
• Water plants differently according to what they need. Check with your local extension service or nurseries for advice.
• Set sprinklers to water the lawn or garden only - not the street or sidewalk.
• Use soaker hoses or trickle irrigation systems for trees and shrubs.
• Keep your yard healthy - dethatch, use mulch, etc.
• Sweep outside instead of using a hose.
• Landscape using "rain garden" techniques to save water and reduce stormwater runoff.

Addressing air pollution in your home - The choices you make at home affect the amount of pollution outside your home as well as inside. Learn what you can do to pollute less and all the while save some money.

Climate change: what you can do at home and in the garden - Making a few small changes in your home and yard can lead to big reductions of greenhouse gas emissions and save money.

Saving Energy

Find Energy Star products for your home - Choosing energy-efficient products can save families about 30% ($400 a year) while reducing our emissions of greenhouse gases. Whether you are looking to replace old appliances, remodel, or buy a new house, you can help. ENERGY STAR is the government's backed symbol for energy efficiency. The ENERGY STAR label makes it easy to know which products to buy without sacrificing features, style or comfort that today's consumers expect.

More steps you can take:

• Turn off appliances and lights when you leave the room.
• Use the microwave to cook small meals. (It uses less power than an oven.)
• Purchase "green power" for your home's electricity. (Contact your power supplier to see where and if it is available.)
• Have leaky air conditioning and refrigeration systems repaired.
• Cut back on air conditioning and heating use if you can.
• Insulate your home, water heater and pipes.

If you’re one of 12 million boat owners in the United States, you can find ways to reduce hydrocarbon and nitrogen oxides emissions from your engine.

How can I get resources to improve my local environment?

The Community Action for a Renewed Environment (CARE) program offers grants to fund collaborative partnerships of local residents, governments and businesses that reduce toxic pollutants in their local environments and minimize people's exposure to those pollutants.

Community Action for a Renewed Environment (CARE)