CEAREX Ice Floe Deformation Data
M.A. Hopkins and W.D. Hibler III
Thayer School of Engineering
Dartmouth College
Hanover, NH 03755 USA
Ice floe deformation data collected during the drift phase of the
Coordinated Eastern Arctic Experiment (CEAREX) are contained in six files
on this CD-ROM, in the directory \SEAICE\DEFORM. Each file holds the
time series of the deformation of a single line defined by a master and
a remote transponder pair. One master transponder (B) was located over
the bridge of the M/V POLARBJORN. The second master transponder (A)
was located on Alpha floe perpendicular to the POLARBJORN at the bridge
location of the first transponder. The master transponders define a
base line perpendicular to the ship and 115 meters in length. The three
remote transponders were located in the vicinity of the ship. Remote 1
was about 1 kilometer dead ahead of the ship. Remote 2 was on Beta floe
about 500 meters from the ship. Remote 3 was beyond Beta floe,
separated from Beta floe by an active lead. The correspondence between
the data files and the master remote pairs is given below:
POS07.DFM master A/remote 2
POS08.DFM master B/remote 2
POS09.DFM master A/remote 3
POS10.DFM master B/remote 3
POS11.DFM master A/remote 1
POS12.DFM master B/remote 1
Raw data were gathered at two minute intervals from year-day ("Julian
Day", JD) 282-320.5. At JD 320.5 the POLARBJORN moved and the baseline was
lost. Gaps in the raw data were linearly interpolated. The data were
smoothed by low passing frequencies at a cutoff frequency of 8 per day.
The smoothed data were then resampled at 15-minute intervals. The accuracy
of the ranges is about plus/minus 0.1 meter. The data in the files consist
of time in year-day ("Julian Day") and the range in meters from the master
to the remote. The Fortran format is (f8.4,2x,f8.1,1x).
Time (JD) f8.4
Blanks 2x
Range (meters) f8.1
Blank 1x
References:
Tucker, W.D. III, D.K. Perovich, M.A. Hopkins, and W.D. Hibler III. 1990.
On the relationship between local stress and strain in arctic pack ice.
Annals of Glaciology 15 (August): 265-270. Proceedings of the
symposium on Ice-ocean Dynamics ad Mechanics held in Hanover, New Hampshire, U.S.A.
Martin, S. and R. Drucker. 1991. Observations of short period ice floe
accelerations during Leg II of the POLARBJORN drift. Journal of Geophysical
Research 96(C6): 10567-10580.
Contact Information:
Mark Hopkins and William D. Hibler III
Thayer School of Engineering
Dartmouth College
Hanover, NH 03755 USA
Phone: 603-646-2608
Telemail: W.HIBLER/Omnet
October 1990 (rev. 8/91)
