Environmental Engineering Reference
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current meters. Getting the heavy railcar wheels to which the meter arrays were anchored
over the side on a heaving icy deck was always a hazardous adventure. I was rapidly learn-
ing how different this would be to working on purpose-built oceanographic ships. We were
equipped with a very early satellite navigation system (GPS) to record exactly where we
had left these lonely arrays. Months later, we would return and try to recover them. Once
we were convinced we were onsite, an acoustic signal would be sent down, which in the-
ory would release the long array of current meters from the railcar wheel. At the upper end
of the array was a brightly coloured float (with a flashing light) that would bring it to the
surface. We would often spend more than a day searching for the float. The sea was usually
rough and the float could be in a wave trough and invisible for much of the time. For half
the year, it was at best twilight and we never encountered a float with the light function-
ing. Over the course of three years, I think we lost about 50% of the current meter arrays,
mostly towards Baffin Island, where they were probably swept away by icebergs.
The weather was a constant problem on that first cruise. It was, of course, winter. The
cold Baffin current flows south along the eastern coast ofBaffin, bringing with it a growing
ice pack at that time of year. Beginning at the coast, the ice consolidates into a continu-
ous field that grows eastwards as winter deepens. It became increasingly difficult to get
anywhere near the Baffin coast. The west coast of Greenland has a north-flowing and re-
latively warm current (an offshoot of a Gulf Stream eddy), but this gave other problems.
Away from the ice, the seas were usually rough, making it quite hazardous handling heavy
oceanographic equipment on the deck. The worst conditions occurred where the cold west-
ern waters rubbed shoulders with the warm waters flowing north in the east. The ship was
always doing its best to imitate an Olympic swimmer doing the breaststroke. The air tem-
perature was below freezing and the flying spray and seas breaking over the bow could
very quickly encrust everything on deck with a heavy shroud of ice. You could distinctly
sense the effect on the ship's stability as it sluggishly recovered from each roll. In these
conditions, the skipper never countenanced a suggestion of stopping for a station. While
every one of us attacked the ship's growing cloak of ice, we would skedaddle as fast as
possible to the cold, calmer water of the ice pack or the warmer waters off Greenland.
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