Andrew Yee
November 24th 05, 04:44 AM
Public Affairs Office
Naval Research Laboratory
Washington, D.C.
10/24/2005
NRL Press Release: 51-05r
NRL scientists detect "milky sea" phenomena
Scientists at the Naval Research Laboratory's Marine Meteorology Division
in Monterey, CA, (NRL-Monterey), working with researchers from Monterey
Bay Aquarium Research Institute and the National Geophysical Data Center,
presented the first satellite detection of a phenomenon known as the
"milky sea." The satellite observations were corroborated by a ship-based
account. This research was published in the October 4, 2005, issue of the
Proceedings of the National Academy of Sciences (PNAS).
Since the 17th century, "milky seas" have been associated more commonly
with maritime folklore than scientific knowledge. They are mentioned in
the Jules Verne classic 20,000 Leagues Under the Sea. Until this satellite
detection was achieved by NRL researchers, the phenomena had only been
reported in ship's logs and their descriptions were subject to the
uncertainties of human perception. Mariners have described the phenomena
as giving the impression of sailing upon a field of snow or gliding over
the clouds -- all under the darkness of a moonless night. The glowing
waters appear to extend to the horizon in all directions, and can last
from several hours to several days. They are thought to be caused by
enormous populations of bacterial bioluminescence, but their ephemeral
nature has made it difficult to place appropriately equipped research
craft in their locations.
Dr. Steven Miller, from NRL's Marine Meteorology Division, explained that
the milky sea presented in the paper was detected by the Defense
Meteorological Satellite Program (DMSP). These polar-orbiting satellites
feature the Operational Linescan System (OLS) instrument, which was
designed primarily to monitor global cloudiness under both solar and lunar
illumination. To achieve nighttime detection, the OLS uses a sensor
capable of registering extremely low levels of visible light. This system
has been used to detect terrestrial and atmospheric emission sources such
as fires, lightning, and human activity (city lights, fishing boats, etc.)
around the world. However, there have been no previous reports or
demonstrations of the OLS being used to detect bioluminescence.
Dr. Miller and the research team searched ship reports of milky sea
sightings since 1992 and compared these with archived OLS satellite data.
A British merchant vessel, the S.S. Lima, was transiting the northwestern
Indian Ocean on the night of January 25, 1995 when it encountered the
milky sea. Enhancement of OLS imagery collected roughly 30 minutes after
the ship's report of initial sighting revealed a massive region of
low-level light emission. The glowing waters spanned an area roughly the
size of Connecticut (over 15000 km**2) and lasted at least three nights.
The event took place in the northwest Indian Ocean, approximately 280 km
off the Somali coast. The boundaries of the feature matched closely with a
surface ship's reported entry and exit of the brightly glowing waters.
Although such observations cannot be fully explained based on the known
features of any light-emitting organism, these so-called "milky seas" are
hypothesized to be manifestations of strong bioluminescence produced by
colonies of bacteria associated with a microalgal bloom in the surface
waters. Because of the lack of scientific observations, a full explanation
of milky seas has remained elusive. With the current state of satellite
technology, and sampling limitations, remote sensing researchers have
generally thought that the detection of bioluminescence emission from
space was unlikely if not impossible.
Demonstration of their detection by low-light detectors on current and
future satellite systems provides a possible means to targeting these
events in the future by properly equipped research vessels. This creates
opportunities for new research and insight pertaining to the cause, role,
and implications of these poorly understood phenomena, said Dr. Miller.
Professor J. Woodland Hastings of Harvard University, a leader in the
field of bioluminescence and communicator of this paper to PNAS, called
this research a "beautiful discovery."
In addition to Dr. Miller, the research team consisted of Dr. Steven
Haddock from Monterey Bay Aquarium Research Institute, Dr. Christopher
Elvidge from the National Geophysical Data Center, and Mr. Thomas Lee from
NRL's Marine Meteorology Division.
IMAGE CAPTION:
[http://www.nrl.navy.mil/pao/PressReleases/2005/Miller-Fig-1.jpg (173KB)]
Study areas (top) corresponding to unfiltered (A-C) and filtered (D-F)
satellite imagery on the night of the SS Lima observations. (A and D) Jan.
25, 1995, 1836 GMT. (B and E) Jan. 26, 1995, 1804 GMT. (C and F) Jan. 27,
1995, 1725 GMT. Arrowheads in F indicate low signal-to-noise ratio
artifacts. Shown in D are the ship track (dashed line) and positions at
time of first sighting on the horizon (point a) and exit from the glowing
waters (point b), based on details of the ship report.
Naval Research Laboratory
Washington, D.C.
10/24/2005
NRL Press Release: 51-05r
NRL scientists detect "milky sea" phenomena
Scientists at the Naval Research Laboratory's Marine Meteorology Division
in Monterey, CA, (NRL-Monterey), working with researchers from Monterey
Bay Aquarium Research Institute and the National Geophysical Data Center,
presented the first satellite detection of a phenomenon known as the
"milky sea." The satellite observations were corroborated by a ship-based
account. This research was published in the October 4, 2005, issue of the
Proceedings of the National Academy of Sciences (PNAS).
Since the 17th century, "milky seas" have been associated more commonly
with maritime folklore than scientific knowledge. They are mentioned in
the Jules Verne classic 20,000 Leagues Under the Sea. Until this satellite
detection was achieved by NRL researchers, the phenomena had only been
reported in ship's logs and their descriptions were subject to the
uncertainties of human perception. Mariners have described the phenomena
as giving the impression of sailing upon a field of snow or gliding over
the clouds -- all under the darkness of a moonless night. The glowing
waters appear to extend to the horizon in all directions, and can last
from several hours to several days. They are thought to be caused by
enormous populations of bacterial bioluminescence, but their ephemeral
nature has made it difficult to place appropriately equipped research
craft in their locations.
Dr. Steven Miller, from NRL's Marine Meteorology Division, explained that
the milky sea presented in the paper was detected by the Defense
Meteorological Satellite Program (DMSP). These polar-orbiting satellites
feature the Operational Linescan System (OLS) instrument, which was
designed primarily to monitor global cloudiness under both solar and lunar
illumination. To achieve nighttime detection, the OLS uses a sensor
capable of registering extremely low levels of visible light. This system
has been used to detect terrestrial and atmospheric emission sources such
as fires, lightning, and human activity (city lights, fishing boats, etc.)
around the world. However, there have been no previous reports or
demonstrations of the OLS being used to detect bioluminescence.
Dr. Miller and the research team searched ship reports of milky sea
sightings since 1992 and compared these with archived OLS satellite data.
A British merchant vessel, the S.S. Lima, was transiting the northwestern
Indian Ocean on the night of January 25, 1995 when it encountered the
milky sea. Enhancement of OLS imagery collected roughly 30 minutes after
the ship's report of initial sighting revealed a massive region of
low-level light emission. The glowing waters spanned an area roughly the
size of Connecticut (over 15000 km**2) and lasted at least three nights.
The event took place in the northwest Indian Ocean, approximately 280 km
off the Somali coast. The boundaries of the feature matched closely with a
surface ship's reported entry and exit of the brightly glowing waters.
Although such observations cannot be fully explained based on the known
features of any light-emitting organism, these so-called "milky seas" are
hypothesized to be manifestations of strong bioluminescence produced by
colonies of bacteria associated with a microalgal bloom in the surface
waters. Because of the lack of scientific observations, a full explanation
of milky seas has remained elusive. With the current state of satellite
technology, and sampling limitations, remote sensing researchers have
generally thought that the detection of bioluminescence emission from
space was unlikely if not impossible.
Demonstration of their detection by low-light detectors on current and
future satellite systems provides a possible means to targeting these
events in the future by properly equipped research vessels. This creates
opportunities for new research and insight pertaining to the cause, role,
and implications of these poorly understood phenomena, said Dr. Miller.
Professor J. Woodland Hastings of Harvard University, a leader in the
field of bioluminescence and communicator of this paper to PNAS, called
this research a "beautiful discovery."
In addition to Dr. Miller, the research team consisted of Dr. Steven
Haddock from Monterey Bay Aquarium Research Institute, Dr. Christopher
Elvidge from the National Geophysical Data Center, and Mr. Thomas Lee from
NRL's Marine Meteorology Division.
IMAGE CAPTION:
[http://www.nrl.navy.mil/pao/PressReleases/2005/Miller-Fig-1.jpg (173KB)]
Study areas (top) corresponding to unfiltered (A-C) and filtered (D-F)
satellite imagery on the night of the SS Lima observations. (A and D) Jan.
25, 1995, 1836 GMT. (B and E) Jan. 26, 1995, 1804 GMT. (C and F) Jan. 27,
1995, 1725 GMT. Arrowheads in F indicate low signal-to-noise ratio
artifacts. Shown in D are the ship track (dashed line) and positions at
time of first sighting on the horizon (point a) and exit from the glowing
waters (point b), based on details of the ship report.