What is Earth's atmosphere made of?
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Nitrogen 78.08%\nOxygen 20.95%\nWater Vapor varies from 0 to 4%\nArgon 0.93%\nCarbon Dioxide 0.036%\nand traces of other gasses.\n\nNote that CO2 is way less than 1%.\n\n(EDIT) After some though I have decided to make a change. The table in my source shows water vapor as being between 0 and 4% of the atmosphere, but I just ignored that because it just doesn't seem like part of the atmosphere, it is more of an additive. Then I realized that it IS a natural part of the atmosphere, but a highly variable part because the temperature of Earth is just right for it to be constantly cycling between liquid and gas. And it is EXTREMELY important because water vapor is a powerful greenhouse gas.  Our CO2 emissions alone can cause only a small amount of global warming. The difference between those scientists who say global is a looming catastrophe and those who say it is no big deal all hinges on how they think the concentration of water vapor responds to the small amount of warming caused by the added CO2, which all by itself, it no big deal. So I have put water vapor back in the list above.
790097
Just look at the moon.  The moon has is made up of mantle rocks, just like the Earth's crust.  But there's no water, nor is there an atmosphere.  \n\nIt's actually not a fair question.  The Earth is in a wonderful position in that water is a liquid (too close it's a gas, too far it's ice).  Water is a very abundant substance - if a planet has an atmosphere, it has water.  The moon is too small and cannot hold an atmosphere, but there's no way the Earth would lose its atmosphere due to its size.  Therefore, there's really no way for the Earth to lose water.\n\nSo assuming the Earth COULD lose its atmosphere, you'd have a surface like the moon.
1150304
Normal air is composed of about 78% nitrogen, 21% oxygen, .93% argon, and around .03-.05% carbon dioxide, among other gases.\n\nGood luck!
168316
The Atmosphere\n\nHow is the atmosphere structured?\nThe atmosphere consists of four distinct layers, which are seperated by a boundaries that end in the suffix "pause". There is a lot of information in the Earth Science Reference Tables page 14. \nTroposphere-This layer of the atmosphere is closest to the earth and 99% of all weather takes place here because most of the water vapor is located here. \nStratosphere-This layer is above the troposphere and contains ozone, which is an important gas, because it absorbs cancer-causing ultra violet rays from the Sun. \nMesosphere-This layer is above the stratosphere. \nThermosphere-This is the uppermost layer of the atmosphere. \nEarth Science Reference Table page 14: \nHow do we describe the present condition of the atmosphere?\nThe present condition of the atmosphere is called WEATHER and it is described using observations of temperature, air pressure, humidity, wind, cloudiness and precipitation. \nWhat is temperature?\nTemperature is a measure of the average kinetic energy of the particles of a substance. In other words, the more molecules vibrate within a substance, the higher the temperature. \nMeasurement - There are three scales that measure temperature: CELSIUS, FAHRENHEIT AND KELVIN scales. There is a conversion scale on page 13 of your ESRT. \nMaps - Meteorologists find it useful to map temperatures and they use lines to connect equal temperatures called Isotherms. \nWhat is air pressure and how is it used to predict the weather?\nAir Pressure - Air pressure is also called barometric or atmospheric pressure. By definition, it is the weight of the atmosphere pushing down on the earth. \nBarometer - A barometer is the instrument that measures air pressure and it uses units of millibars (mb) or inches of mercury (inches). \nFactors that affect air pressure:\nTemperature - As the temperature of the air increases, the air pressure decreases, which is an indirect relationship. \nHumidity - As the humidity of the air increases, the air pressure decreases, which is an indirect relationship.\nYou might ask "WHY?": Humid air is lighter than dry air. When water vapor enters dry air, it does not squeeze in between the molecules of air. Instead, the water vapor pushes out many of the air's heaviest molecules like Nitrogen and Oxygen. In other words, lighter molecules of water vapor replace heavier molecules and the result is the air weighs less and therefore has less air pressure. \n\nHigh air pressure - means that the atmosphere is heavy at that location and from our notes above, you can conclude that the air is probably cool and dry (if you are not sure, see notes above). So, if the barometer indicates high pressure or rising air pressure, you can conclude that the weather will be cool and dry. \nLow air pressure - means that the atmosphere is not heavy at that location and from our notes above, you can conclude that the air is probably warm and humid (if you are not sure, see notes above). So, if the barometer indicates low pressure or falling air pressure, you can conclude that the weather will be warmer and humid. \nMaps - Meteorologists find it useful to map air pressure and they use lines to connect equal equal air pressures called Isobars
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Gas, air, the atmosphere - it's made up of molecules of gas, each of which has mass.  That mass is attracted to the Earth by gravity.  Light as air is, it still has mass that it captured by Earth's gravity.  When an asteroid  comes along and smacks into the Earth, water vaper and air are throw far out into space, several hundreds of miles (the atmosphere is only about 100 miles high).  However, it all comes back due to the force of gravity.\n\nHowever, Earth's gravity is not strong enough to hold the lightest elements, hydrogen and helium.  That is the reason Earth is a small rocky planet and not a gas giant like Jupiter or Saturn, or even the sun.  Get big enough and you can attract even the lightest elements - which adds mass - which attracts more gas - which adds more mass - etc etc etc.\n\nThat's why your idea, unfortunately, won't work.  Gravity.
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Yes. The first atmospheres were composed of hydrogen and helium. \n\nWhen the protosun began nuclear fusion in its core it soon started blasting the planets with radiation. The atmospheres heated up and since heat is kinetic energy in between atoms and molecules it now became possible for atmospheric elements to reach escape velocity and leave their respective planet. \n\nMercurys atmosphere was doomed from the beginning being so close to the sun and having so little mass. Although there are some gasses left, like sodium, those gasses are also being blasted off into space. Mercurys atmosphere is so thin it is a more perfect vacuum than we can reproduce here on earth.\n\nVenus lost most of its hydrogen and helium. The water vapour was split into hydrogen and oxygen by ultraviolet radiation with the hydrogen quickly escaping. Heavier gasses like CO2 and nitrogen remains. Venus has about as much nitrogen, per mass, in its atmosphere as earth does and about as much CO2 that earth had in the beginning.\n\nFor earth every atom lighter than 3 U can reach escape velocity. That is why there is no He3 left while there is still some He4. Earths atmosphere was alot denser in the beginning. After the lighter elements had been blasted off there was enormous amounts of CO2 in the atmosphere. Unlike Venus earth became cold enough to condensate the water vapour. The CO2 began dissolving into the primordial oceans where chemical reactions began turning the H2CO3 into solid carbonates that settled on the bottom. This thinning was later accelerated by life. Finally life began producing oxygen that also got trapped by biochemical reactions as ironoxides that settled onto the bottom of the oceans. It took billions of years for the oceans to run out of iron until eventually oxygen began building up in the atmosphere. The atmopshere earth has now is earths third.\n\nMars was also too small to keep a significant atmosphere but it was able to survive for much longer than on Mercury because it is farther from the sun. Still only a little CO2 remains while even the nitrogen, which had to have been there, has escaped. Most of the water has suffered the same fate as the water on Venus. Interesting that mars has about the same amount of CO2, by mass, in its atmosphere while Venus has about the same amount of nitrogen. Percentage wise Venus atmosphere is almost identical to Mars only about 10000 times as dense.\n\nFurther out the gas giants have been able to hold on to their primordial atmospheres despite relentless solar radiation.
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do u mean the substances in the atmosphere?\n\nif so than the signgle most important part that keeps us from the bad influence of UV and Infra red radiance is the Ozone, which comprises the ozone layer.\nCertainly the other gasses that form the atmosphere on the earth are important because they form the atmosphere without which we would freeze during nights and melt during days.\nthose are the gases like N2 and O2
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Nitrogen is the major gas present in the earth's atmosphere(78%), followed by Oxygen(21%) and the rest 1% of other gases like Argon, hydrogen etc.
126270
I believe all the layers create a balance to sustain life on the third planet from the sun. The main layer-the troposphere-is half of the atmosphere and closest to the earth. It contains the natural gases for life and makes our weather. Without it, the water cycle would be impossible. The stratosphere's high stability level lets us fly aircraft within it. The ozone layer which controls how much sun touches our tan is in the stratosphere. Most potentially dangerous meteorites burn away in the mesosphere. The space shuttle can only orbit around the world with the thermosphere. That's where auroras are made. The upper limits(what I like to call the "crust" of our atmosphere) is the exosphere. I hope this helped.
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I assume you mean for humans.\n\nAir (particularly Earths air mixture of oxygen, carbon and nitrogen), Water, and plants. We couldn't survive long if any of the three did not exist.
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Oh I know,  I know, is it the ozone? neeee Oh I'm sorry the answer we were looking for was actually atmosphere. Sorry little johnny better luck next time on guess that ocean of air around the Earth.
251225
it was a ball of burning gas that seperated from the sun billions of years ago, got trapped in the suns gravity and began revolving around it, and in time it cooled down and formed the earth, but it was still too hot for life, it cooled more and more and the atmosphere shaped from the fumes rising from it, eventually it rained and made huge oceans on earth which later became the home for the first cells that later made all different living things.
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Like the person said above.  0.038% of the atmosphere is made up of CO2.  That's 3.8 parts per million.  So that's why it won't take very much for people to double the amount of CO2 that is naturally occuring.
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Oxygen = O\nNitrogen = N\nCarbon Dioxide = CO2\n\nThey take up the space that is allowed them by the gravity and temperature of the planet, but oxygen and nitrogen form the main two constituents of the atmosphere.
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Humans doesn't have the ability to destroy the atmosphere. We can only polute it. The only way to destroy the atmosphere is to blow up planet earth.
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It has a thick, dense atmosphere that is almost entirely nitrogen, like 98%. It is one of only four celestail bodies with a thick atmosphere: earth, Venus, Mars, and Saturn's moon Titan. Other planets or moons have very thin, wispy atmospheres about 1/800,000 that of earth's, but these are nothing more than trace gases and not a true atmosphere.
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Nitrogen is the most abundent element in our atmosphere.  Bacteria gets N2 from the air.