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You cannot download interactives. An atmosphere is the layers of gases surrounding a planet or other celestial body. These gases are found in layers troposphere, stratosphere, mesosphere, thermosphere, and exosphere defined by unique features such as temperature and pressure.
The atmosphere protects life on earth by shielding it from incoming ultraviolet UV radiation, keeping the planet warm through insulation, and preventing extremes between day and night temperatures. The sun heats layers of the atmosphere causing it to convect driving air movement and weather patterns around the world. Teach your students about the Earth's atmosphere with the resources in this collection. We live at the bottom of an invisible ocean called the atmosphere, a layer of gases surrounding our planet.
Nitrogen and oxygen account for 99 percent of the gases in dry air, with argon, carbon dioxide, helium, neon, and other gases making up minute portions. Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Image Moon Earth Troposhere Silver-blue noctilucent clouds are shown extending far above the orange-colored troposphere, the lowest and densest part of Earth's atmosphere. Twitter Facebook Pinterest Google Classroom.
Encyclopedic Entry Vocabulary. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. Media If a media asset is downloadable, a download button appears in the corner of the media viewer. Text Text on this page is printable and can be used according to our Terms of Service. Nearly all of the water vapor and dust in the atmosphere are in this layer and that is why clouds are found here.
The stratosphere is the second layer. It starts above the troposphere and ends about 31 miles 50 km above ground. Ozone is abundant here and it heats the atmosphere while also absorbing harmful radiation from the sun. The air here is very dry, and it is about a thousand times thinner here than it is at sea level.
Because of that, this is where jet aircraft and weather balloons fly. The mesosphere starts at 31 miles 50 km and extends to 53 miles 85 km high. The top of the mesosphere, called the mesopause, is the coldest part of Earth's atmosphere, with temperatures averaging about minus degrees F minus 90 C.
This layer is hard to study. Jets and balloons don't go high enough, and satellites and space shuttles orbit too high.
Scientists do know that meteors burn up in this layer. The thermosphere extends from about 56 miles 90 km to between and miles and 1, km. Temperatures can get up to 2, degrees F 1, C at this altitude. The thermosphere is considered part of Earth's atmosphere, but air density is so low that most of this layer is what is normally thought of as outer space.
In fact, this is where the space shuttles flew and where the International Space Station orbits Earth. This is also the layer where the auroras occur. Charged particles from space collide with atoms and molecules in the thermosphere, exciting them into higher states of energy. The atoms shed this excess energy by emitting photons of light, which we see as the colorful aurora borealis and aurora australis.
The exosphere , the highest layer, is extremely thin and is where the atmosphere merges into outer space. It is composed of very widely dispersed particles of hydrogen and helium. Earth is able to support a wide variety of living beings because of its diverse regional climates, which range from extreme cold at the poles to tropical heat at the Equator.
The majority of this production is from oceanic plankton — drifting plants, algae, and some bacteria that can photosynthesize. One particular species, Prochlorococcus, is the smallest photosynthetic organism on Earth. Calculating the exact percentage of oxygen produced in the ocean is difficult because the amounts are constantly changing.
Scientists can use satellite imagery to track photosynthesizing plankton and estimate the amount of photosynthesis occurring in the ocean , but satellite imagery cannot tell the whole story. Studies have shown that the amount of oxygen in specific locations varies with time of day and with the tides.
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