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Development of Arctic Science
and Instrumentation for
Geology and Geophysics
Bernard
Coakley, Geophysical Institute, University of Alaska
Bernard.Coakley@gi.alaska.edu
Exploration of the Arctic Ocean has always relied
on the availability of equipment suitable for Arctic deployment and access
to Arctic-capable platforms. After World War II, national security needs
dictated an active research presence in the Arctic. This research presence
was supported through air-serviced ice islands and occasional ice-breaker
cruises. These arduous programs deployed sensors similar to those used at
lower latitudes, collecting the data that began to fill in the blank spot
of the Arctic map.
While these programs produced much "new" knowledge, establishing
the broad outlines of the basin morphology and oceanography, they were
severely limited by the restricted mobility of ice islands and
icebreakers, which, limited by or borne by the pack ice, prevented the
execution of structured surveys. Airborne magnetic surveys provided the
first comprehensive view of the Arctic Ocean basin, but, limited by the
lack of co-registered bathymetric data, these data have not been of much
use outside of the Eurasian basin.
Early nuclear-powered submarine cruises in the Arctic Ocean sometimes
visited ice island research stations. The drifting scientists were
impressed by this mobility, unhindered by ice, and speculated about how it
might be used for science. While much of the bathymetry data collected
during these classified cruises was recently declassified and released,
systematic surveys of the Arctic seafloor were not conducted until the
SCICEX program of unclassified cruises on Sturgeon class fast-attack
submarines.
The initial SCICEX cruises utilized only the ship's own narrow-beam bottom
sounder and a Bell BGM-3 marine gravimeter. With NSF funding, new sonars,
designed for submarine operations in the Arctic Ocean, were developed and
installed on the USS Hawkbill. These sonars were used during SCICEX 98 and
99 to collect swath bathymetry and chirp sub-bottom profiler data across
the entire Arctic Ocean basin, focusing on the Lomonosov and Gakkel Ridges
in the Eurasian basin.
We now know a good deal about the Gakkel and Lomonosov Ridges and the
eastern edge of the Chukchi Plateau. The primary objectives for future
cruises are obscured by the wind-thickened ice pack north of Greenland and
Arctic Canada (eg. Alpha Ridge and the northern shelf and slope of North
America) or are remote and difficult to achieve (eg. Mendeleev Ridge). The
instruments and platforms used to explore these features will need to
solve the same problems that have been solved before. A particular problem
for submarines and AUVs is automating data acquisition and acquiring
precision under-ice navigation.
The development of Arctic Ocean exploration from drifting ice islands to
structured surveys conducted with purpose built instruments is continuing
today, as evidenced by this meeting. A variety of science problems,
articulated by results from lower latitude and the need to develop fully
global models of climate and plate tectonics are driving the development
of new research platforms and new, appropriate tools for basin
exploration. As a result of this work, it appears likely that in the next
decade there will be a coherent program of scientific drilling and AUV
exploration of the Arctic Ocean.
Site maintained by
Cindy
Hanrahan Last updated:
May 14, 2004
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