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19 April, 1999
Woke up to see Elephant Island...the home to Shackleton's crew during their
incredible epic of survival...his ship frozen into the ice pack on January
18th, 1915...eventually crushed October 27, 1915...they made their way over
the ice and open sea to Elephant Island...arriving in April, 1916...22 men
left on Elephant Island when Shackleton and 5 of his best set out in an
open boat for South Georgia Island where there was a whaling station...a 22
foot boat to cross the most dangerous ocean in the world, 800 miles of open
ocean, in the dead of the Antarctic winter...Shackleton's story of survival
through leadership is considered to be one of the greatest of it's type in
recorded history...his leadership resulted in the loss of not one life in
over a year of being stranded in the most hostile environment on earth...a
place where NASA and NSF (the National Science Foundation) fund the study
of life forms because of the similarity of the environment to the extremely
hostile environments found on other planets and moons of our solar
system...whether that be extreme cold or the superheated hydrothermal vent
environment where life has been detected in temperature as high as 90
degrees Celsius.
Well, we finally reached station 1. This was now being called "Science Day
1." I dressed to stay warm on deck: thermals, wool socks, gloves, wool cap,
hood and snow jacket. It was 1 degree Celsius with a 22-knot wind blowing.
This means there was a wind chill of -13 degrees Celsius. Wind chill is the
effective temperature. A group of about 5 chin strap penguins were swimming
in front of the bow as we slowly moved through the water, using the sonar
to ping the bottom for an instrument that was left 3 years ago to measure
pressures. Using a hydrophone, we attempted to "talk" to it by sending
messages that should have activated it to begin sending its position data.
It didn't. It was unknown initially whether it was even there or if the
batteries had failed. Finally the decision was made to send the signal to
release the sensor from the ocean floor and we would intently scan the
surface. Rising from over 1000 meters, it would take about 10 minutes for
the sensor to surface, but no one knew for sure the ascension rate. Unknown
to a few of us on the top deck (intently staring into the swimming ocean
waves!), the device began to report it's position after receiving the
release command. It was firmly stuck to the bottom. Our next plan was to
move upwind, drop 4000 meters of cable with a grapple hook and drag a
semicircle around it, stopping and then reeling the cable in so that it
would catch tight about the base and hopefully either dislodge it or snag
it. The operation took several hours, when you consider our winch fed out
and reeled in cable around 40 meters per minute, and this slowed to 10
meters/min once we believed we were in a certain area where we thought the
sensor was. Finally we snagged something where we thought we should. The
cable grew taut and we waited, aware that we'd be racing time if it
dislodged and floated to the surface. Currents would pick it up and...
Suddenly, the unexpected happened, whether a combination of tension or
wave-action, the cable suddenly snapped. We lost 1500 meters of cable and
several hours of work. That was it. It was decided this was all we could
do. We set out for station 2, where we would do the helium and trace metal
sampling, as well as graph real time data on temperature, salinity, and
depth. En route, we saw icebergs and the spouts of several whales, which
looked like the ocean itself was venting into the sky...but these were not
the vents we are hunting...
The vents we are hunting have plumes of superheated water that result from
ocean water seeping into cracks in the surface of the earth. As it
percolates down it gets closer and closer to the magma below. This heats it
to well above the boiling point at the surface (100 degrees Celsius), but
the great pressure at the bottom keeps boiling from occurring (the same way
a radiator or pressure cooker keep boiling from occurring, allowing for
hotter cooking temperatures, basically the great pressure keeps the boiling
bubbles from occurring and this allows the water to remain in the liquid
phase longer). This superhot water readily dissolves all kinds of minerals
from the earth's crust, but under such high temperatures, it does expand
and become more buoyant (just like a hot air balloon). This causes it to
force its way to the seafloor surface where it vents into the cold ocean
water. This causes the dissolved minerals to quickly become solids again
and precipitate out of solution, leading to a build-up of minerals that
form chimneys around the vent. As the plume rushes out of the seafloor,
this precipitation causes the plume to take on a range of colors, including
black, hence the name "Black Smokers." Because the plumes are generated in
the earth's crust, they are rich in helium-3, an isotope of helium (where
does our helium on earth come from? Is there a global helium resource
issue? Why? Should helium be available to the public for things like
balloons? Why or why not?). Detecting elevated helium levels is a good sign
of vent activity.
We will be working around the clock now. There is much to do and many
stations to sample. En route to our next station, winds picked up to 40
knots and seas piled up. Our chief scientist came into the lab and said "no
one on deck." And for good reason: our 300-foot ship was being tossed as I
attempted to write my journal. The winds were so hard that they were
stripping the tops right off of the waves, smashing them into an aerosol
and then blasting them into the Antarctic night, stealing their potency as
entire wavetops disappeared in a wind-whipped spray. By the time we'd
reached our next station, several aboard had turned in due to being
seasick… Nevertheless, the call of science was too strong… once on station,
all metereological distractions were shook off and all plunged into the
night's sampling as though the sea were as flat as glass. We finished at 1
AM and called it a night for the 5 AM arrival at our next station.
Until later,
Shawn
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The following are weather and environmental data for any who are awaiting
them
(as advertised : )
Depth Lat. (S) Long (W) Date Time Temp Baro Wind /direction salinity
(m) deg min deg min gmt (C) mbar m/s - degrees ppt
3779 58 49.9 58 1.9 4/18 1850 2.5 998.4 11 - 300 33.7
907 60 50.7 54 4.2 4/19 0957 0.9 986.8 9.5 - 340 34.1
so the bottom line reads 907 meters depth, 60 degrees 50.7 minutes South
(of equator), 54 degrees 4.2 minutes west (of prime meridian), on 4/19 at
0957 (Greenwich mean time), 0.9 degrees Celsius (water temp), 986.8
millibars of pressure (normal atmosphere is about 1000 mbar), with winds at
9.5 meters per second from the north-northwest (340 degrees on a compass),
with a salinity reading of 34.1 parts per thousand (that’s 34.1 grams of
salt per liter of water, since a liter = 1000 g).
And finally, a question from a faithful reader : )
Q: "As a High School and Junior High School Science and
Physical Science Teacher, I wondered as soon as I heard
of your voyage: Will you be looking for those organisms
which produce food using heat rather than photosynthesis?
I understand that they live and reproduce in the thermal
vents in the oceans."
A: "We have two biologists aboard exactly for that purpose- to collect and
preserve any organisms dredged up near the vents. They are "hot" right now
for a couple reasons - there's big bucks available for study of "life in
extreme places" (hot, cold, anaerobic, etc) because these will guide us in
our quest to discover life outside of earth's biosphere and because these
organisms have adaptations never seen before, so their biochemistry offers
the potential of new mechanisms, new reactions, new ways of dealing with
issues that puzzle us (aging? oxidation? electron "production", waste
treatment, cancer cures, etc). Many have been found _around_ vents, not in
them.
They don't actually use the heat as their source of energy, they seem to be
adapted to the heat, which may reduce the competition, they are called
"chemolithoautotrophs" - which means they are able to fix inorganic carbon
by themselves from the chemical energy bound (usually) in sulfides (H2S,
etc). By oxidizing these, they obtain the energy necessary to reduce
dissolved CO2 into the molecules of life (ATP, carbohydrates, and proteins).
Me, dressed for the Antarctic cold!
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