Source ID NPEO NPEO NPEO NPEO NPEO NPEO NPEO
Platform ID NPEO-2001 NPEO-2002 NPEO-2003 NPEO-2004 NPEO-2005 NPEO-2006 NPEO-2008
Project Name North Pole Environmental Observatory North Pole Environmental Observatory North Pole Environmental Observatory North Pole Environmental Observatory North Pole Environmental Observatory North Pole Environmental Observatory North Pole Environmental Observatory
Region/location North Pole North Pole North Pole North Pole North Pole North Pole North Pole
Institution University of Washington University of Washington University of Washington University of Washington University of Washington University of Washington University of Washington
Investigator Dr. Richard Moritz Dr. Richard Moritz Dr. Richard Moritz Dr. Richard Moritz Dr. Richard Moritz Dr. Richard Moritz Dr. Richard Moritz
Contact email dickm@apl.washington.edu> dickm@apl.washington.edu> dickm@apl.washington.edu> dickm@apl.washington.edu> dickm@apl.washington.edu> dickm@apl.washington.edu> dickm@apl.washington.edu>
Project web site
Documentation files Mooring_NP2001_ULS_22_ReadMe.txt NPEO_2002-03_Mooring_ULS_ReadMe.txt Mooring_NP2003-04_ReadMe.txt Mooring_NP2001_ULS_22_ReadMe.txt Mooring_NP2001_ULS_22_ReadMe.txt NPEO_2006-2008_MooringULS_Readme.txt file.   Mooring_NP2008_ULS_22_ReadMe.txt
Method Moored ULS Moored ULS Moored ULS Moored ULS Moored ULS Moored ULS Moored ULS
Draft, freeboard, or thickness draft draft draft draft draft draft draft
Instrument model and maker APL/UW Mark 2 Upward Looking Sonar APL/UW Mark 2 Upward Looking Sonar APL/UW Mark 2 Upward Looking Sonar APL/UW Mark 2 Upward Looking Sonar APL/UW Mark 3 Upward Looking Sonar APL/UW Mark 2 Upward Looking Sonar APL/UW Mark 2 Upward Looking Sonar
Instrument Serial Number 22 12 45 17 310 60 2305
Point Data location NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/ NSIDC,  ftp://sidads.colorado.edu/pub/DATASETS/ARCSS/data/arcss156/
Point Data files Mooring_NP2001_ULS_22_5min_ver1_unix.txt Mooring_NP2002_ULS12_10min.txt   Mooring_NP2004_ULS17_7min.txt Mooring_NP2005_ULS310_5min_prelim.txt uls_60_2006_2008_5min_final_V1.txt uls_2305_2008_2010_8min_final_V1.txt
Header files
Latitude maximum 89.557 89.458 89.389 89.455 89.253 89.35 89.53
Latitude minimum              
Longitude maximum 33.647 53.638 46.119 54.329 64.692 77.12 84.38
Longitude minimum              
Start date  2 April 2001 22 April 2002 22-Apr-2004 22-Apr-2005        1 June 2006      17 April 2008
Start year 2001 2002 2003 2004 2005 2006 2008
Start day 92 113 115 112 113 152 108
Stop date   27 April 2002 21 April 2003 16-Apr-2005 16-Jul-2005       30 June 2007   30 February 2010
Stop year 2002 2003 6/26 2005 July 2007 2010
Stop day 109 112 118 106 2005 152 32
failed after 2 days failed after 85 days
Total number of point samples 99469 44419 0 66327 24482 15569 122609
Total number of PDF's and averages 13 12 0 13 4 7 23
PDF nbins 300 300   300 300 300 300
PDF bin width 0.100 0.100   0.100 0.100 0.100 0.100
PDF first center 0.000 0.000   0.000 0.000 0.000 0.000
PDF sample intervals 5 min 10  Min   7 min 5 min 5 min 8 min
 
Mooring specific information
Mooring name NPEO NPEO NPEO NPEO NPEO NPEO NPEO
Mooring depth 4293.0 4297.0 4301.0 4295.0 4305.0 4315.0 4304.0
Instrument depth 49.0 54.0 56.0 76.0 75.0 49.0 49.0
ADCP none yes   none none none none
Pseudo-spatial sampling none none   none none none none
Ping frequency (hz) 300 kHz 300 kHz 300 kHz 300 kHz 300 kHz 300 kHz 300 kHz
Ping beam width 2 degrees 2 degrees 2 degrees 2 degrees 2 degrees 2 degrees 2 degrees
Ping interval  5 minutes plus 10 secs for two 25-minute periods each day 10 minutes plus 10 secs for two 25-minute periods each day 5 minutes plus 10 secs for two 25-minute periods each day 7 minutes plus 10 secs for two 25-minute periods each day 5 minutes plus 10 secs for two 25-minute periods each day 5 minutes plus 10 secs for two 25-minute periods each day 8 minutes plus 10 secs for two 25-minute periods each day
 
Processing Notes Version 1.0 Version 1.0 Version 1.0 Version 0.0, preliminary Version 1.0 Version 1.0
Summary statistics and PDFs were computed from the 5 minute data Summary statistics and PDFs were computed from the10 minute data Summary statistics and PDFs were computed from the 7 minute data Summary statistics and PDFs were computed from the 5 minute data.  Only 7 months had more than 10% data coverage. Summary statistics and PDFs were computed from the 5 minute data Summary statistics and PDFs were computed from the 8 minute data
 
 
 
ATTENTION - PRELIMINARY DATASET NOTE ON DATA QUALITY AND MISSING DATA:  This ULS instrument 
These data were acquired by the Mark 3 APL ULS (ULS3), which differs serial number 60 experienced two serious 
from the Mark 2 APL ULS (ULS2) used on previous NPEO moorings.  In  operational problems during 2006-2007 at NPEO:  
particular, the sonar pulse-width is 0.15 milliseconds for ULS3  (i) Due to a broken electrical connection, this ULS
compared to 1.00 milliseconds for ULS2, and the detection threshold acquired no useable pressure data at depth.  The depth data in
for ULS3 is set relative to the sonar receiver baseline noise level. this data file are estimates based on the pressure measurements
In ULS2 the detection threshold is a fixed voltage.  Inspection of  of a Seabird CTD positioned approximately 5 meters below the 
this preliminary data set indicates the POSSIBILITY OF BIAS in  ULS on the mooring line.  The Seabird depth data were 
the ULS3 ice draft measurements, compared to ULS2.  The ULS3 records adjusted by a constant (-5.05m) to estimate the ULS depth.
much more detailed sonar information than ULS2, and investigations (ii) The acoustic transducer circuit of ULS60 drifted from 
are currently underway to quantify the bias.  DATA USERS ARE  pre-deployment calibrations, causing a reduction of ULS
CAUTIONED THAT A REVISED ULS 310 2005-2006 DATASET WILL SUPPLANT transmit and receive sensitivity.  As a result, the signal
THIS PRELIMINARY DATASET IN CALENDAR 2009.  This preliminary dataset can received at the ULS was often lower than the threshold for 
be used with confidence to assess time changes in ice thickness detection of surface targets, i.e. the bottom of the ice
during the period of operation of ULS 310. and open water.  When the signal is below the detection 
threshold, no sonar range is recorded and the missing data
indicator -999.000 is entered for DRAFT in the dataset. 
Additional details are presented in the 
NPEO_2006-2008_MooringULS_Readme.txt file.