ISS016-E-27426
| NASA Photo ID | ISS016-E-27426 |
| Focal Length | 400mm |
| Date taken | 2008.02.05 |
| Time taken | 15:10:24 GMT |
Resolutions offered for this image:
1000 x 629 pixels 540 x 340 pixels 540 x 334 pixels 3032 x 2064 pixels 639 x 435 pixels
1000 x 629 pixels 540 x 340 pixels 540 x 334 pixels 3032 x 2064 pixels 639 x 435 pixels
Spacecraft nadir point: 13.5° N, 12.0° W
Photo center point:
Photo center point by machine learning:
Photo center point:
Photo center point by machine learning:
Nadir to Photo Center:
Spacecraft Altitude: 179 nautical miles (332km)
Country or Geographic Name: | AFRICA |
Features: | PAN-LARGE THUNDERSTORM ANVIL |
| Features Found Using Machine Learning: | |
Cloud Cover Percentage: | 50 (26-50)% |
Sun Elevation Angle: | 47° |
Sun Azimuth: | 228° |
Camera: | Kodak DCS760c Electronic Still Camera |
Focal Length: | 400mm |
Camera Tilt: | High Oblique |
Format: | 3060E: 3060 x 2036 pixel CCD, RGBG array |
Film Exposure: | |
| Additional Information | |
| Width | Height | Annotated | Cropped | Purpose | Links |
|---|---|---|---|---|---|
| 1000 pixels | 629 pixels | No | Yes | Earth From Space collection | Download Image |
| 540 pixels | 340 pixels | Yes | Yes | Earth From Space collection | Download Image |
| 540 pixels | 334 pixels | Yes | Yes | NASA's Earth Observatory web site | Download Image |
| 3032 pixels | 2064 pixels | No | No | Download Image | |
| 639 pixels | 435 pixels | No | No | Download Image |
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Image Caption: Cumulonimbus Cloud over Africa
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.
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.
