Current Events

  • Atmospheric CO2 Level Tops 400 ppm
    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm rep...Read more

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    Atmospheric CO2 Level Tops 400 ppm

    During the week of May 13th, the CO2 level at the Mauna Loa Observatory in Hawaii topped 400 ppm repeatedly. Daily levels of CO2 can vary due to weather, and there are seasonal trends as well. The level of atmospheric greenhouse gases continues to increase, now over 120 ppm since the Industrial Revolution began. For more on the Keeling Curve, see http://keelingcurve.ucsd.edu/. Find out more about greenhouse gases and warming.
  • Massive Tornado Outbreak on Tornado Alley
    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Io...Read more

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    Massive Tornado Outbreak on Tornado Alley

    The week of May 19 brings dozens of tornadoes to Tornado Alley in the states of Oklahoma, Kansas, Iowa, Illinois and Missouri. On May 20th, a massive tornado struck Moore, Oklahoma, devastating communities - destroying over 100 homes and hitting two elementary schools and a hospital - with many casualties and deaths. Our thoughts are with our friends and colleagues suffering from these storms. For more on the May 20th storms, see the NOAA Storm Prediction Center Storm Report.
  • Kansas Legislator Proposes Bill to Outlaw Sustainability Education
    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of ...Read more

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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.

Earth's Atmosphere

The atmosphere is a mixture of nitrogen (78%), oxygen (21%), and other gases (1%) that surrounds Earth. High above the planet, the atmosphere becomes thinner until it gradually reaches space. It is divided into five layers. Most of the weather and clouds are found in the first layer.

The atmosphere is an important part of what makes Earth livable. It blocks some of the Sun's dangerous rays from reaching Earth. It traps heat, making Earth a comfortable temperature. And the oxygen within our atmosphere is essential for life.

Over the past century, greenhouse gases and other air pollutants released into the atmosphere have been causing big changes like global warming, ozone holes, and acid rain.

<a href="/earth/Atmosphere/clouds/mammatus.html">Mammatus clouds</a> are pouches of clouds that hang underneath the base of a cloud. They are usually seen with <a href="/earth/Atmosphere/clouds/cumulonimbus.html">cumulonimbus clouds</a> that produce very <a href="/earth/Atmosphere/tstorm.html">strong storms</a>. This photograph of mammatus clouds was taken on June 21, 2006 in Boulder, Colorado, at sunset. Notice how the light from the sun highlights the round features of these clouds.<p><small><em> Courtesy of Roberta Johnson</em></small></p><a href="/earth/Atmosphere/tstorm/tstorm_lightning.html">Lightning</a> is the most spectacular element of a <a href="/earth/Atmosphere/tstorm.html">thunderstorm</a>. A single stroke of lightning can <a href="/earth/Atmosphere/temperature.html">heat</a> the air around it to 30,000 degrees Celsius (54,000 degrees Fahrenheit)! This extreme heating causes the air to expand explosively. The expansion creates a shock wave that turns into a booming <a href="/earth/Atmosphere/tstorm/lightning_thunder.html">sound wave</a>, better known as thunder.<p><small><em> Image Courtesy of University Corporation for Atmospheric Research/Carlye Calvin</em></small></p><a href="/earth/Atmosphere/NLC.html">Noctilucent</a> clouds are the highest clouds in the sky, but they are not associated with weather like the <a href="/earth/Atmosphere/clouds/cloud_types.html">other clouds</a> we regularly see in the sky.  Noctilucent clouds form very high in the <a href="/earth/Atmosphere/overview.html">atmosphere</a>, in the <a href="/earth/Atmosphere/mesosphere.html">mesosphere</a>.  They are best seen from Earth at sunset. This image was taken on June 15, 2007, in Budapest, Hungary.  Normally seen from locations near the <a href="/earth/polar/polar.html">poles</a> of the Earth, in recent years they have also been seen at much lower-latitude locations.<p><small><em> Image Courtesy of NASA/Veres Viktor</em></small></p>An image of Hurricane Sandy taken by the GOES-13 satellite on October 28. This category 1 <a href="/earth/Atmosphere/hurricane/hurricane.html">hurricane</a> was huge, spanning a horizontal distance of about one-third the US continental landmass. The storm came onshore in New Jersey, and gradually moved northeast. The storm disrupted the lives of tens of millions in the eastern US, doing billions of dollars in damage, resulting in over 30 deaths. Visit the National Hurricane Center's webpage on <a href="http://www.nhc.noaa.gov/">Hurricane Sandy</a> for details.<p><small><em>Image courtesy of NASA</em></small></p>Anti-crepuscular rays are beams of sunlight that appear to converge on a point opposite the sun. They are similar to crepuscular rays, but are seen opposite the sun in the sky. Anti-crepuscular rays are most frequently visible near sunrise or sunset. This photo of anti-crepuscular rays was taken at sunset in Boulder, Colorado. Crepuscular rays are usually much brighter than anti-crepuscular rays.<p><small><em> Image Courtesy of Carlye Calvin</em></small></p>

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Explore Earth's Atmosphere

Layers of the Atmosphere

The atmosphere is divided into five layers. It is thickest near the surface and thins out with ...Read more

Weather

Weather is the state of the atmosphere at a given time and place. Most weather takes place ...Read more

Climate

Warm near the equator and cold at the poles, our planet is able to support a variety of living ...Read more

The Polar Atmosphere

Phenomena in the Polar Atmosphere There are some unique phenomena that happen in the atmosphere ...Read more

Atmospheric Optics

Have you ever seen clouds in the sky that looked different than "normal" clouds? Or have you ...Read more

Air Pollution

What do smog, acid rain, carbon monoxide, fossil fuel exhausts, and tropospheric ozone have ...Read more

Ozone Holes

The Ozone Hole is a major "thinning" of the ozone layer in Earth's atmosphere. It ...Read more

Modeling the Atmosphere

Clouds are an important part of Earth's weather and climate. Scientists use computer models ...Read more

Arts and Culture About Clouds, Weather, and Climate

Whether it is how an artist paints the shapes of clouds or how a poet describes a gloomy weather ...Read more

Atmosphere News

Read about current science, happenings and discoveries related to Earth's atmosphere! ...Read more

More about Earth's Atmosphere

Historical Events

5/24 Nicholas Copernicus, a Polish astronomer, died on this date in 1543 Details
5/30 7.5 magnitude quake hits Quetta, Pakistan in 1935
5/31 7.9 magnitude earthquake hits Peru in 1970

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Did you know?

Did you know that the upper atmosphere of the Earth overlaps with the Earth's ionosphere?

Did you know that you can now share your poems about our collection of cloud art photos. Have fun!

 

Earth and Space Science Concept of the Day

Do you know what this word or phrase means?

Aa
xAa : Hawaiian name for a type of lava flow with a surface that is broken into rough angular fragments which develop during cooling and loss of gas from pahoehoe flows.

Click on the word to find out!

Research Highlights

New Findings Indicate Sediment Composition Affected the Strength of Sumatran Earthquake

Sumatra experiences frequent seismic activity because it is located near the boundary of two of Earth's tectonic plates. Earthquakes occur at 'subduction zones,' such as the one west of Indonesia, when...Read more

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