African Vegetation: Comparing July 1984 and July 1994
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For many years, scientists have believed that the southern expansion of the Sahara has been due to human activity. However, results from the AVHRR instrument and its measurements of vegetation suggest a different explanation: rainfall patterns. In drier years (1984 was one of the driest summers in recorded history in Northern Africa), the Sahara expands south, but in wetter years (such as 1994), vegetation moves back and there is no net expansion of the Sahara as had been previously suggested.
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A fade between NDVI data of Northern Africa from July 1984 and July 1994, showing a recession of the Sahara
Duration: 9.0 seconds
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NDVI measures of African continent, July 1984
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NDVI measures of African continent, July 1994
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NDVI measures of north Africa, July 1984
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NDVI measures of north Africa, July 1984
Available formats:
640 x 486
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599 KB
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66 KB
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NDVI measures of north Africa, July 1994
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NDVI measures of north Africa, July 1994
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| Animation Number: | 589 |
| Animator: | Jesse Allen (Lead) |
| Studio: | SVS |
| Completed: | 1999-01-01 |
| Scientists: | Compton Tucker (NASA/GSFC) |
| | Sharon Nicholson (Florida State University) |
| Instruments: | NOAA-11/AVHRR
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| | NOAA-12/AVHRR |
| | NOAA-7/AVHRR |
| | NOAA-8/AVHRR |
| Data Collected: | 1984/07, 1994/07 |
| Video: | SVS1999-0008 * |
Keywords:
DLESE
>> Climatology
DLESE
>> Physical geography
SVS
>> Sahara
GCMD
>> Location
>> Africa
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More Information on this topic available at:
stories/NDVI/africa_july8494.html
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Please give credit for this visualization to
NASA/Goddard Space Flight Center
Scientific Visualization Studio |
*Please note: the SVS does not fulfill requests for copies of the tapes in our library. On some of our animation pages, there is a direct link to a video distribution service from which tapes, handled by the Public Affairs Office (PAO)/Goddard TV, including some of our animations may be ordered. General information on this service can be found here. |
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