Plankton
Blooms, Capricorn Channel
High-resolution
image (710 Kb)
Detailed imagery
taken by astronauts from the International Space Station has provided
a new way of looking at many features on the Earth's surface. This
image captures a plankton bloom in the Capricorn Channel off the
Queensland coast of Australia. The whispy pattern of the bloom suggests
that the plankton are Trichodesmium -- photosynthetic cyanobacteria,
also called "sea saw dust" that is common in the world's oceans.
Trichodesmium is frequently observed around Australia this time
of year. In fact, Captain Cook's ship's logs written while sailing
in Australian waters in the 1700s contain detailed descriptions
of Trichodesmium blooms. Trichodesmium species are particularly
important because of their role as primary producers: By sheer abundance,
they fix a large amount of carbon dioxide and nitrogen.
Astronauts
frequently photograph large plankton blooms during their missions
because a significant portion of the station orbits cross long stretches
of ocean. In the process, astronauts become acute observers of subtle
changes in sea surface dynamics. Imagery of surface plankton blooms
are multi- dimensional visualizations -- in space and time -- for
the unique physical and chemical circumstances that support the
blooms. Astronauts are trained and encouraged to document phytoplankton
blooms and to make repeated observations to better understand the
longevity and temporal variations of the blooms. Only recently have
astronauts had the capability of documenting these ocean features
at high
resolutions. Each pixel represents a square with sides estimated
to be 6 to 8 meters (20 to 26 feet). The inset box shows zooms in
on part of the bloom to illustrate the level of detail available.
Astronaut photograph
ISS005-E-21572
was provided by the Earth Sciences and Image Analysis Laboratory
at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway
to Astronaut Photography of Earth.
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