US Submarines

Organizations

Polar Science Center, Applied Physics Laboratory, University of Washington

US Navy Arctic Submarine Laboratory

Cold Regions Research and Engineering Laboratory

Principal contacts

Dr. Mark Wensnahan, PSC, email: thinice at apl.washington.edu

Dr. Terry Tucker, CRREL

Data web site

http://nsidc.org/data/g01360.html

Methodology

Upward Looking Sonar on submarines using analog charts (US-Subs-An) or digital recording (US-subs-Dg)

Location

Arctic Ocean

Time interval

1960-2014

Data processing notes

See documentation. The point data have been averaged for clusters that fall within 50-km diameter circles, so where the submarine has turned or crossed back over its track, more than 50-km of track length is used for a single average distribution.

V20130819: cluster averages were computed by M. Wenshanhan

V20151208: cluster averages for 4 new cruises: 1960a, 1960b, 1969c, 1970a. The cluster averages were computed (by rwl) from the series point data recently archived at NSIDC. These four cruises are saved in separate summary and distribution files.

 

20181121: 2011 and 2014 Cruises were added. Data 2011 from the USS-Connecticut (2011-Conn) and USS-New Hampshire (2011-NH) cruises were originally recorded as "Peak Return" rather than the typical "First Return". Using data from cruises were both values were available, we corrected the 2011 peak return data to first return by using an empirical fit using mean and standard deviation for 500 adjacent points. This results in a lower spatial resolution of the resulting data. 2014 Hampton (2014-HT) data were processed in the same fashion since first return based data are still awaiting declassification. 2014 New Mexico (2014-NM) were recorded as first return but using a different recording system. For more documentation on the processing see:

ftp://sidads.colorado.edu/DATASETS/NOAA/G02187/sea_ice_draft/documentation/Processing-Notes-2011-2014-SCICEX-uls-data.pdf.

Number of samples

44 cruises, 1968 50-km average samples. Note that addtional Historical US Submarine data digitized from LeSchack 1980 are available here.

Documentation

Point data

http://nsidc.org/data/g01360.html

Citations

National Snow and Ice Data Center. 1998, updated 2015. Submarine upward looking sonar ice draft profile data and statistics. Boulder, Colorado USA: National Snow and Ice Data Center/World Data Center for Glaciology. Digital media.

Rothrock, D.A. and M. Wensnahan, "The accuracy of sea-ice drafts measured from U. S. Navy submarines", J. Atmos. Oceanic Technol., doi:10.1175/JTECH2097.1, 2007. pdf file

Wensnahan, M., and D. A. Rothrock, 2005. Sea-ice draft from submarine-based sonar: Establishing a consistent record from analog and digitally recorded data. Geophysical Research Letters 32, L11502, doi:10:1029/2005GL022507.

Tucker, W. B. III, J. W. Weatherly, D. T. Eppler, D. Farmer and D. L. Bentley. 2001. Evidence for the rapid thinning of sea ice in the western Arctic Ocean at the end of the 1980s. Geophys. Res. Let.28 (14): 2851-2854.

Acknowlegements

The U.S. analog data were processed at the Polar Science Center at the University of Washington and provided with documentation by M. Wensnahan and D. A. Rothrock. These data were prepared with funding from NSF Office of Polar Programs.

From the NSIDC documentation: "Researchers making use of these invaluable data owe a debt of gratitude to the present and past staff of the Arctic Submarine Laboratory, San Diego, California, for their long-term stewardship of the data. Without guidance from ASL, and in particular without the collaboration of D. Bentley, J. Gossett, and T. Luallin release of these data to the scientific community would not be possible. The Arctic Submarine Laboratory holds raw data from all U.S. submarine cruises beginning with the first cruise under the ice in 1958."

Skate 1962     Honolulu 2003

all cruise tracks

Cruise tracks from all declassified data.

 

Interannual variation     annual cycle from US submarine data

Interannual variation and annual cycle of ice draft from US submarines. Red is summer, blue is winter. The black lines are the results of a mutiple linear regression procedure.

spatial field of ice drafts

Spatial field of ice draft from a linear multiple regrssion procedure. See

Rothrock, D. A., D. B. Percival, and M. Wensnahan,' The decline in arctic sea-ice thickness: Separating the spatial, annual, and interannual variability in a quarter century of submarine data', J. Geophys. Res., 113, C05003, doi:10.1029/2007JC004252, 2008.