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The Antarctic Iceberg Tracking Database
1978 & 1992-2013 (Brigham Young University)
Nathan Madsen, Steven Reeves, Keith Stuart, Ben Lambert, Jarom Ballantyne, and David G. Long
Last database update: May 16,  2013 (for current positions click here)


Iceberg Tracks
(Iceberg Tracks from 1999-2010)

Using six different satellite scatterometer instruments, we have produced an iceberg tracking database.  The BYU database includes icebergs identified in enhanced resolution scatterometer backscatter images during July-Sept. 1978 (from Seasat), July 1996-June 1997 (from NSCAT), 1992-2001 (from ERS-1/2), June 1999-November 2009 (from QuikSCAT), 2008-present (from ASCAT), 2012-present (from OSCAT). Images were obtained from the Scatterometer Climate Record Pathfinder (SCP) project.

Data sets from six different spaceborne scatterometer instruments are used to track icebergs.  For each data set, resolution enhancement is performed by BYU's Scatterometer Image reconstruction (SIR) and/or SIR Filtering (SIRF) algorithms.  The scatterometer instruments used in this study are the Seasat-A Satellite Scatterometer (SASS), the European Space Agency's Remote Sensing Satellite 1(2) (ERS-1/-2), the NASA Scatterometer (NSCAT), the QuikSCAT/SeaWinds scatterometer (QSCAT), the MetOp-A Advanced Scatterometer (ASCAT), and the Indian Space Research Organization's Oceansat-2 scatterometer.  The Seasat-A scatterometer (SASS) was a dual-polarization Ku-band (14.6 GHz) scatterometer that operated from July to Sept. 1978. Using the SIRF algorithm, Antarctic images are generated every 12 & 48 days (a longer time is required for SASS compared to other instruments due to the sampling characteristics of the nominally 50 km backscatter measurements). The ERS-1/2 spacecraft carried a C-band (5.3 GHz) active microwave instrument (AMI).  The scatterometer mode provides nominally 50 km resolution data.  Using SIR, Antarctic images are produced every 6 days.  The ERS-1/2 scatterometers operated from Jan. 1992 to Jan. 2001.  The NSCAT scatterometer is a Ku-band Doppler radar similar to SASS, but with dual-side measurement capability and a dense 25 km resolution sampling.  Using SIRF, Antarctic images were produced every 3 days.  The NSCAT mission lasted from Sept. 1996 to June 1997.  QuikSCAT was launched as a ``quick recovery'' mission to help fill the gap created by loss of NSCAT due a satellite failure.  This scatterometer allows daily images of Antarctica to be created.  QuikSCAT operated from July 1999 to November 2009. ASCAT was launched in October of 2006 and is currently operational. ASCAT operates at C-Band (5.255 GHz) at vertical polarization only. The SIRF algorithm applied to ASCAT (Standard BYU ASCAT Land/Ice Proudcts) generates images from 1 and 2 days of data over Antarctica. Iceberg tracks for ASCAT have only been done back to the beginning of the ASCAT data. This provides an overlap of two data sets (QuikSCAT and ASCAT) for a few years (October 2006 to November 2009).  The Oceansat-2 scatterometer data set begins August 2011 and continues to the present.  Its antenna geometry and frequency are similar to that of QuikSCAT.  Primary tracking has shifted to the Oceansat-2 scatterometer.

The initial position for each iceberg is located based on either (1) a position reported by the National Ice Center (NIC)'s web page (http://www.natice.noaa.gov//pub/icebergs/Iceberg_Tabular.pdf) or (2) by the sighting of a moving iceberg in a time series of scatterometer images.  From an initial start point, the iceberg is tracked in the scatterometer image time series. Gaps in the position track result from missing scatterometer data and from the occasional loss of contrast between the iceberg and surrounding area during summer months.  For each image a lat/lon position is reported for each iceberg.

Iceberg positions are reported in a separate ASCII text file for each iceberg. The file name is the same as that of the iceberg.  For example the file "b27.ascat" contains the position track information for B27 from ascat.  A few lines from the b27.ascat file are shown below:

lat: -72.8568 lon: -119.7036 day: 326 2009 file: msfa-a-Ant09-326-326.sir backscat: -7.657
lat: -72.8927 lon: -119.8380 day: 327 2009 file: msfa-a-Ant09-327-327.ave backscat: -9.348
lat: -72.9339 lon: -119.6691 day: 328 2009 file: msfa-a-Ant09-328-328.ave backscat: -8.874

Note that latitude and longitude are specified in decimal degrees with positive North and East, respectively.  The day is specified as: "day of the year" year. The file lists the scatterometer image file from the SCP image set used to track the selected position.  The backscat data is the backscatter value returned by the scatterometer.

The iceberg database can be obtained via the links shown below.  If desired, data can be imported into Microsoft Excel or other spreadsheet programs as "space delimited data". Note that ASCAT and OSCAT data files are in a more abbreviated format than those of previous data files.

As of January 2012 OSCAT is being used primarily to track icebergs.  While ASCAT is still active the ASCAT archive only extends to that point. The QuikSCAT database has been updated and revised through November 23 2009. The QuikSCAT satellite is no longer operational.

DATABASE FILES
ASCAT portion of the database in a gzipped tar file from the SCP web site: icebergDatabase_ascat.tar.gz
QSCAT portion of the database in a gzipped tar file from the SCP web site: icebergDatabase_qscat.tar.gz
OSCAT portion of the database (which is still incomplete) in a gzipped tar file from the SCP web site: icebergDatabase_oscat.tar.gz
All other portions (SASS, ERS-1/2, NSCAT) in a gzipped tar file from the SCP web site: icebergDatabase_other.tar.gz

Individual iceberg tracking files are available for each sensor through the web links below.

INSTRUMENT
TIME PERIOD
SASS
July 1978 - Sept. 1978
ERS-1/2
Jan. 1992 - Jan. 2001
NSCAT
Sept. 1996 - June 1997
SeaWinds
April 2003 - October 2003
QSCAT
July 1999 - November 2009
ASCAT
November 2009 - Present
OSCAT
November 2010 - Present

Related papers:
K.M. Stuart and D.G. Long, "Tracking large tabular icebergs using the SeaWinds Ku-band microwave scatterometer", Deep-Sea Research Part II, to appear, doi:10.1016/j.dsr2.2010.11.004, Vol. 58, pp. 1285-1300, 2011. (1.6 MB PDF)
D.G. Long, Jarom Ballantyne, and C. Bertoia, "Is the Number of Icebergs Really Increasing?" EOS, Transactions of the American Geophysical Union, Vol. 83, No. 42, pp 469 & 474, 15 Oct. 2002. (620 kB PDF)
K.M. Stuart and D.G. Long, "Iceberg Size and Orientation Estimation using SeaWinds", Cold Regions Science and Technology, doi:10.1016/j.coldregions.2011.07.006, 2011. (1.7MB PDF)

An older report further describing this multidecadal database of Antarctic icebergs observed with scatterometer data is available in pdf format from the SCP web site at IcebergReport.

Support from both NASA and NSF is acknowledged.

Last Revised: May 16, 2013



For further information contact:

Dr. David G. Long                                  long@ee.byu.edu
Professor, Electrical and Computer Eng. Dept. http://www.ee.byu.edu/
Brigham Young University                       http://www.byu.edu/
459 Clyde Building                               voice: 801-422-4383
Provo, Utah    84602                               fax: 801-422-0201

Microwave Earth Remote Sensing (MERS) Lab:  http://www.mers.byu.edu/
Scatterometer Climate Record Pathfinder:    http://www.scp.byu.edu/