|
|
10 July, 2001
Ice Coring and Collection
Tuesday, 10 July 2001
Valkommen! (Welcome!)
Life on Board
Our flock of marine birds is still with us. I have discovered by
observation that when we are traveling through open water they dive into
the churned-up waters behind the boat. When we are sitting in open water,
they usually hang around in a flock near the front or side of the boat
where the thruster engines, which are used to keep our position stable,
shoot water out. Perhaps this water is a little warmer or perhaps they
just churn up some food. When we are going through ice, the ship crunches
up and turns over chunks of ice that have brown algae on the bottom. Small
polar cod become caught in this algae and the birds have a nice fish
dinner. When we are sitting at an ice station, they sit around
disconsolately in groups on the ice, shifting uncomfortably from foot to
foot. One of the scientists onboard, who is also a member of the Swedish
Ornithological Society, brought his birdwatching scope. With his help, we
identified the species of birds in our resident flock. Black-legged
kittiwakes, skua, Glaucus gulls, and what he translated as Laughing gulls,
all wheel and skim the surface then dive repeatedly into the frigid water
in search of sustenance. I wonder if they will accompany us all the way to
the North Pole?
Where Are We Now?
I woke up to snow this morning! We are still at the same Marginal Ice
Station because the biogeochemical group is collecting snow and ice samples
but this afternoon we will leave for an open water station. There is no
wind so the kite team can't launch and it is too foggy to fly the
helicopter, so the atmospheric chemistry group can't really collect data.
In the Arctic, weather conditions are extremely variable and all of the
science is dependent upon conditions favorable to each parcticular
experiment, so sometimes you sit and wait (but there is always something to
do).
Scientists at Work
I got to go out on the ice again, this time to help collect ice cores.
They use a small hand-held, gasoline-powered engine mounted on top of a
coring tube, which is approximately 1 meter high. Two people hold on to
the engine's handles and guide the corer into the ice. Once it is flush
with the ice surface, you give it a sharp tug that triggers some latches on
the bottom to close, capturing the ice inside the tube. You then lift up
the whole thing and dump the core into a U-shaped ice core holder with
centimeter marks on the side. One person measures the entire length while
the other begins to cut the core into pieces with a saw. They are most
interested in the bottom 20 cm. The lowest 5 cm is where most of the
organisms collect and then the rest is analyzed for salinity (how much salt
is in the water), and other nutrients. The salts collect at the bottom of
the ice because as the ice sits around, over time the seawater is flushed
down to the bottom by melting and rain or snow. This salt-concentrated
water is now called brine and the organisms that live there have developed
special techniques for dealing with the high salinity. The scientists
take the pieces of core and melt them so that they can determine the
species of the organisms living in this unique environment.
Vi ses! (See you later!)
From Deck 4 on the Icebreaker Oden, somewhere northeast of Spitzbergen,
Dena Rosenberger
Finnish scientist Tuomo Roine and I, measuring and cutting an ice core. The corer tube is in the background.
Contact the TEA in the field at
.
If you cannot connect through your browser, copy the
TEA's e-mail address in the "To:" line of
your favorite e-mail package.
|