FOR IMMEDIATE RELEASE
May 13, 2003
Contact: Dr. Mark Johnson, Professor,
Institute of Marine Science,
School of Fisheries & Ocean Sciences, University of Alaska Fairbanks. (907) 474-6933.
Buoys Track Cook Inlet Currents
COOK INLET, Alaska—Navigating
Alaska's Cook Inlet might seem a fairly easy task. After all, the inlet
is more than 20 miles wide in places. But looks are deceiving. Lying in
wait to make life difficult and sometimes deadly for fishermen, cargo
ship captains and offshore oil and gas platform operators is a mix of
swift currents, whirlpools, and sandbars that seem to come and go. And
that's just in the summer. During winter, add to the mix hazards like
pack ice that at best slows ship traffic and at worst closes the inlet
to vessels entirely.
And then there are notorious tides that periodically raise and lower the
inlet's water level by nearly 40 feet. That kind of fluctuation makes
Cook Inlet second only to Nova Scotia's Bay of Fundy.
Into this chaotic marine world scientists from the University of Alaska
Fairbanks School of Fisheries and Ocean Sciences and the Woods Hole Oceanographic
Institution recently placed three specially equipped research buoys. The
buoys will drift throughout the summer with the inlet's currents and tides
as part of a three-year study to understand how these powerful forces
affect sea ice and sediments in the region. The three buoys were released
northeast of Kalgin Island, within the inlet's narrows, in early April
with the help of Cook Inlet Spill Prevention and Response, Inc.
Mark Johnson, oceanographer at the UAF Institute of Marine Science, said
the buoys and images recorded by orbiting satellites will help him and
his colleagues create accurate computer models of the inlet to better
understand these interactions. The study is funded by the federal Minerals
Management Service through the Coastal Marine Institute at the University
of Alaska Fairbanks School of Fisheries and Ocean Sciences.
"With 2-D and 3-D ice-ocean computer models, we will be able to simulate
tidal rips, wind-driven and thermohaline circulation in Cook Inlet,"
said Johnson. "The bouys drifting with currents in the inlet will
provide the real-world data we need to verify how well these models work."
Over the study's three years, Johnson and his colleagues will deploy about
45 beachball-size buoys into the inlet and track them as they drift. The
researchers will recover the buoys each fall, or after they run aground
or drift into the Gulf of Alaska. Throughout the winter, scientists will
monitor currents using satellites that track ice movement in the inlet.
UAF researcher Steve Okkonen said computer models are widely used tools
that in this case will help scientists better understand how Cook Inlet
currents distribute sediment and impact ice. Such a model is needed for
Cook Inlet as ship traffic, as well as oil and gas exploration, increase
in the waterway. Okkonen said better models that predict where the huge
amounts of sediment that flow from rivers into the inlet each summer will
end up also is important to the placement of undersea power cables, telecommunications
and oil and gas pipelines.
Mark Johnson recently returned from a year-long sabbatical as The Office
of Naval Research Arctic Chair in Polar Marine Science at the U.S Naval
Postgraduate School in Monterey, California.
Editors Note:
Following the distribution of this news release, we learned that Cook
Inlet does not experience the second most dramatic tidal change in North
America. Our information came from the Alaska Almanac, but it is incorrect.
According to the National Ocean Service, the top six locations for largest
average tidal ranges are within the Bay of Fundy in Nova Scotia, Canada.
Alaska's Turnagain Arm in Upper Cook Inlet ranked number 12 while the
Port of Anchorage ranked number 33.
