Cumulonimbus Cloud over Africa

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    Perhaps the most impressive of cloud formations, cumulonimbus (from the Latin for “pile” and “rain cloud”) clouds form due to vigorous convection (rising and overturning) of warm, moist, and unstable air. Surface air is warmed by the Sun-heated ground surface and rises; if sufficient atmospheric moisture is present, water droplets will condense as the air mass encounters cooler air at higher altitudes. The air mass itself also expands and cools as it rises due to decreasing atmospheric pressure, a process known as adiabatic cooling. This type of convection is common in tropical latitudes year-round and during the summer season at higher latitudes.

    As water in the rising air mass condenses and changes from a gas to a liquid state, it releases energy to its surroundings, further heating the surrounding air and leading to more convection and rising of the cloud mass to higher altitudes. This leads to the characteristic vertical “towers” associated with cumulonimbus clouds, an excellent example of which is visible in this astronaut photograph. If enough moisture is present to condense and heat the cloud mass through several convective cycles, a tower can rise to altitudes of approximately 10 kilometers at high latitudes and to 20 kilometers in the tropics before encountering a region of the atmosphere known as the tropopause—the boundary between the troposphere and the stratosphere.

    The tropopause is characterized by a strong temperature inversion. Beyond the tropopause, the air no longer gets colder as altitude increases. The tropopause halts further upward motion of the cloud mass. The cloud tops flatten and spread into an anvil shape, as illustrated by this astronaut photograph. The photo was taken from a viewpoint that was at an angle from the vertical, rather than looking straight down towards the Earth’s surface. The image, taken while the International Space Station was located over western Africa near the Senegal-Mali border, shows a fully formed anvil cloud with numerous smaller cumulonimbus towers rising near it. The high energy levels of these storm systems typically make them hazardous due to associated heavy precipitation, lightning, high wind speeds and possible tornadoes.

    Credit: NASA

    NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

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    straup, Tejas Katdare, Danya R, and 254 other people added this photo to their favorites.

    View 12 more comments

    1. Abdulrahman Bakheet 49 months ago | reply

      سبحان الله
      سبحان الله

      قال الله تعالى في القران الكريم
      هو الذي يريكم البرق خوفا وطمعا وينشئ السحاب الثقال

      Allah says in the Koran

      It is he who doth show you the lightning, by way both of fear and of hope: it is he who doth raise up the clouds, heavy with (fertilizing) rain

      Thank you NASA on this wonderful picture

    2. tommy tui 49 months ago | reply

      the miracle of photography is encapsulated in this image .Llongyfarchiadau NASA

    3. Ray Love 49 months ago | reply

      Love these clouds, I reckon Christ will return on such a cloud as this. Anyway Im happy to be able to see such a thing.

    4. maricriscf♥♪ 49 months ago | reply

      omg! This is amazing!!

    5. William A. LaCrosse III ~ lonewolv 49 months ago | reply

      the cloud is there to protect africans from becoming african americans.

    6. PDQuesnell 49 months ago | reply

      What always amazes me about clouds is that they are just tons and tons of water, just floating up in the sky.

      Such a nice planet. I like it here.

    7. gemini angel's art and dolls 49 months ago | reply

      i am speechless....WOW!!

    8. suesviews 49 months ago | reply

      thanks for sharing this

    9. billie stock 49 months ago | reply

      it looks so tiny but so big!
      awesome photo.

    10. OakleyOriginals 49 months ago | reply

      Wow! What an image!!!

    11. La Pom  48 months ago | reply

      Thanks for sharing this wonderfull shot.

    12. steve p2008 48 months ago | reply

      great from space but not so beautiful from underneath

    13. pedro ramon rodriguez quintana [deleted] 48 months ago | reply

      WoW..this is jet a real photograph of clouds..fantastic,this is realy win me..

    14. pedro ramon rodriguez quintana [deleted] 48 months ago | reply

      If you want to know more about the vulcanos or fenomenous atmospheric,please check my site on flirckr and view the links to got aout of a web of cintific studies in Spain abouth this fenomenous...thank you..

    15. o_r_i_t 48 months ago | reply

      Outstanding. Thank you for sharing these amazing images of our earth and allowing us to see it in a way most of us would never have the chance otherwise.

    16. nili.berl 48 months ago | reply

      fantstic !!!
      Thanks NASA ,

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