2001 EARTH SCIENCE VIDEOTAPES |
| |
Tape Title | Record ID |
Date Produced | TRT: |
Synopsis |
| MICROBES RIDE THE DUST | G01-047 | 06/14/01 |
00:14:05 | NASA-funded researchers have discovered
that bacteria and fungi are being transported in plumes of North
African dust that cross the Atlantic Ocean and arrive in the Americas
and the Caribbean. Dust storms and the rising warm air can lift dust
10,000 feet or so above the African deserts and then out across the
Atlantic, many times reaching as far as the Caribbean where they
often require the local weather services to issue air pollution
alerts. Recent studies have linked disease born illnesses and the
decline of the coral reefs in the Caribbean to the increasing
frequency and intensity of Saharan dust events.
|
TAPE CONTENTS: |
| ITEM (1): Dust Particle
Landscape - Microbes transported by dust storms in North
Africa have been hitching rides across the Atlantic--living in the
highly irregular nooks and crannies found in the surfaces of dust
particles. These images were taken by an electron microscope
magnified 12,000 & 8,000 times. Notice the moon-like craters which
protect the microbes from exposure to ultraviolet radiation from the
Sun. Scientists also think that upper altitudes of the dust clouds
deflect harmful UV rays, shielding microbes at lower altitudes as
they are transported across the Atlantic Ocean. Additionally, when
dust clouds move over open water in lower latitudes, the moderate
temperatures and high humidity are known to enhance microbial
survival.
a) Dust Image Magnified 12,000 Times
b) Dust Image Magnified 8,000 Times
Courtesy: USGS
|
| ITEM (2): MICROBES RIDE THE
DUST ANIMATION - The dust comes every year during northern
Africa's dry season, when storm activity in the Sahara Desert and
Sahel generate clouds of dust. The dust originating from fine
particles in the arid topsoil is transported into the atmosphere by
winds and may be carried in excess of 10,000 feet high into the
atmosphere by easterly trade winds. Typically, it takes 5 to 7 days
for the dust clouds to cross the Atlantic Ocean and reach the
Caribbean and Americas. This animation illustrates microbes hitching
rides across the Atlantic in the highly irregular nooks and crannies
found in the surfaces of dust particles and how they are transported
across the Atlantic Ocean.
Courtesy: NASA
|
| ITEM (3): TOMS Data
Visualizations - During the peak of the 2000 dust season,
scientists collected samples of airborne pollutants and dust daily on
the island of St. John in the Virgin Islands. The results show that
high levels of microbes were collected on the days that NASA's Total
Ozone Mapping Spectrometer (TOMS) satellite instrument observed the
African dust sweeping into the region, indicating that the microbes
had been transported from Africa. The TOMS data were rendered and
combined with a world map to help scientists track the progress of
the clouds of dust. The tan and orange colors in these images
primarily show high concentrations of dust. Some aerosols from
biomass burning can also be seen.
a) TOMS July 2000 Aerosol Index
b) TOMS May - June 14,1983 Aerosol Index (dustiest year on record)
Courtesy: NASA
|
| ITEM (4): Dust Images From
Around The World - The Sea-viewing Wide Field-of-view Sensor
(SeaWiFS) on board the Orb View-2 Satellite, has captured images of
dust storms around the globe. According to the recent studies, high
dust frequency is not necessarily a result of the decreased rainfall,
but rather its cause.
1) Off the northwestern coast of the African Continent, February,
26th 2000 - a dust storm the size of Spain
2) Mediterranean Sea
a)July 18th 2000 from north Africa towards Italy
b) April 18th 2001 northward from Egypt
All three continents bordering the Mediterranean Sea are subject to
affects of dust storms.
3) Middle East, May 20th 1999
Courtesy: NASA/ORBIMAGE
|
| ITEM (5): Air Sampling B-Roll
- Dr. Virginia Garrison, USGS, collects samples of airborne
pollutants and dust daily on the island of St. John in the Virgin
Islands. The samples are then sent to the USGS laboratory in St.
Petersburg, Florida, for microbial analysis.
Courtesy: Murphy Entertainment Group
|
| ITEM (6): Culturing Air
Filters B-Roll - Dr. Christina Kellogg cultures samples
from St. John in lab. Courtesy: University of
South Florida TV/USGS
|
| ITEM (7): Culturing Organisms
B-Roll - Fungi and bacteria that survive the trans-Atlantic
journey in dust include bacterial or fungal cultures that do not
produce disease mixed with species that do produce disease in both
humans and plants. A fungus, which has been isolated in African dust,
Aspergillus sydowii, has been determined to cause Sea Fan
disease in coral reefs throughout the Caribbean. Desert dust
exposure has also been identified as a source of terrestrial disease
outbreaks including: Aspergillosis in animals, and
Coccidioidomycosis. B-roll of Drs. Dale Griffin & Christina Kellogg
culturing samples from St. John in lab.
Courtesy: Murphy Entertainment Group
|
| ITEM (8): Coral Images
- A fungus, which has been isolated in African dust,
Aspergillus sydowii, has been determined to cause Sea Fan
disease in coral reefs throughout the Caribbean. Recent studies have
linked the decline of the coral reefs in the Caribbean to the
increasing frequency and intensity of Saharan dust events.
Courtesy: NASA/CPN TV
|
| ITEM (9): SOLVING THE MYSTERY
- Dr. Garriet Smith looking at fungi specimens through
microscope in his lab located at the University of South Carolina,
Aiken. Dr. Smith and his team determined that a fungus called
Aspergillus sydowii, caused Sea Fan disease in coral reefs
throughout the Caribbean.
Courtesy: Murphy Entertainment Group
|
| ITEM (10): TOMS Spacecraft
Animation - NASA's Total Ozone Mapping Spectrometer (TOMS)
satellite instrument has been used to identify atmospheric conditions
such as dust events and other aerosols. Such satellite images enable
scientists to notify localities of approaching African dust clouds so
that precautions can be taken for those with respiratory problems.
Courtesy: NASA
|
| ITEM (11): Interview Excerpts
- Dr. Dale Griffin, Microbiologist,
United States Geological Survey, Center For Coastal Geology And
Regional Marine Studies
Courtesy: University of South Florida TV/USGS
|
Earth Science Gallery