README FILE FOR UNIV. WASHINGTON SBI NORTHERN CHUKCHI MOORING DATA June 2006 (updated April 2013) ================================================================================ Shelf Basin Interactions (SBI) Moorings 3 and 4 during 2002-03 and 2003-04 -------------------------------------------------------------------------- This is an archive of data from four moorings (SBI3-02, SBI4-02, SBI3-03 and SBI4-03) deployed by the University of Washington (UW) at two sites in the northern Chukchi Sea from July 2002 to September 2004, with mooring turn-around during September 2003. Moorings were: - deployed in 2002 from the USCGC Polar Star (SBI cruise AWS02), - recovered and redeployed in 2003 from the USCGC Healy (SBI cruise HLY-03-03) - finally recovered in 2004 from the USCGC Healy (SBI cruise HLY-04-04). Sponsorship for this mooring work came from ONR Grant Number N00014-02-1-0305. Moorings SBI3 were located near 73° 20.3' N 166° W, in ~ 70 m of water. Moorings SBI4 were located near 73° 36.7' N 166° W, in ~ 110 m of water. Moorings SBI3 carried - at ~ 48 m depth, RDI-ADCP current meter (upward-looking, with ice tracking) - at ~ 55 m depth, Aanderaa RCM-7 current meter - at ~ 60 m depth, Sea-Bird SBE-16 Temperature-Conductivity recorder. Moorings SBI4 carried - at ~ 52 m depth, RDI-ADCP current meter (upward-looking, with ice tracking) - at ~ 56 m depth, Sea-Bird SBE-16 Temperature-Conductivity recorder. - at ~ 76 m depth, Aanderaa RCM-7 current meter - at ~ 96 m depth, Sea-Bird SBE-16 Temperature-Conductivity recorder. This archive is of data from all ADCP, SBE and RCM instruments. Mooring Year Latitude Longitude Instrument S/N Instr. Water ID Deployed Depth Depth SBI3-02 2002 - 73° 20.328' N 166° 03.589' W - ADCP 2270 - 48m 71m SBI3-02 2002 - 73° 20.328' N 166° 03.589' W - RCM-7 11456 - 56m 71m SBI3-02 2002 - 73° 20.328' N 166° 03.589' W - SBE-16 1397 - 61m 71m SBI4-02 2002 - 73° 36.680' N 166° 02.513' W - ADCP 2230 - 52m 108m SBI4-02 2002 - 73° 36.680' N 166° 02.513' W - SBE-16 05 - 56m 108m SBI4-02 2002 - 73° 36.680' N 166° 02.513' W - RCM-7 1926 - 76m 108m SBI4-02 2002 - 73° 36.680' N 166° 02.513' W - SBE-16 1226 - 96m 108m SBI3-03 2003 - 73° 20.331' N 166° 03.549' W - ADCP 2232 - 48m 72m SBI3-03 2003 - 73° 20.331' N 166° 03.549' W - RCM-7 6493 - 55m 72m SBI3-03 2003 - 73° 20.331' N 166° 03.549' W - SBE-16 02 - 60m 72m SBI4-03 2003 - 73° 36.662' N 166° 02.549' W - ADCP 2332 - 52m 107m SBI4-03 2003 - 73° 36.662' N 166° 02.549' W - SBE-16 1541 - 56m 107m SBI4-03 2003 - 73° 36.662' N 166° 02.549' W - RCM-7 11454 - 76m 107m SBI4-03 2003 - 73° 36.662' N 166° 02.549' W - SBE-16 1700 - 96m 107m For RCMs and SBEs, data are recorded in one file per instrument per year. with naming convention: SBIN_yyyy_III#####.txt N=mooring ID; yyyy=Deployment year; III=instrument type; ####=serial number. For the ADCPs, there are multiple files per instrument. SBIN_yyyy_ADCP#####.000 = Binary data file downloaded from the ADCP The remainder are ASCII conversions of this file, corrected for clock drift and magnetic declination. SBIN_yyyy_#####.btm = ASCII bottom track data (including ice range and velocity) SBIN_yyyy_#####.ins = ASCII instrument data (e.g. heading, pitch, roll, temperature) SBIN_yyyy_#####_bin01.rdat = ASCII water velocity data from Bin 1 SBIN_yyyy_#####.bin02.rdat = ASCII water velocity data from Bin 2 etc. (Bin depths are given in the data files) Header information is included in each data file. ------------------------------------------------------------------------------- For project overviews, please see: http://psc.apl.washington.edu/HLD (and references therein) http://psc.apl.washington.edu/HLD/SBI2003/SBIHealy2003.html and http://arctic.bio.utk.edu/sbi/ For published discussion of related measurements and their interpretation, please see: Roach, A.T., K. Aagaard, C. H. Pease, S.A. Salo, T. Weingartner, V. Pavlov, and M. Kulakov, Direct measurements of transport and water properties through Bering Strait, J. Geophys. Res., 100, 18,443-18,457, 1995. Weingartner, T., K. Aagaard, R. Woodgate, S. Danielson, Y. Sasaki, and D. Cavalieri, Circulation on the north central Chukchi Sea shelf, Deep-Sea Res. II, 52 (24-26), 3150-3174, 2005. Weingartner, T.J., D.J. Cavalieri, K. Aagaard, and Y. Sasaki, Circulation, dense water formation, and outflow on the northeast Chukchi shelf, J. Geophys. Res., 103, 7647-7661, 1998. Woodgate, R.A., and K. Aagaard, Revising the Bering Strait freshwater flux into the Arctic Ocean, Geophys. Res. Lett., 32, L02602, doi:10.1029/2004GL021747, 2005. Woodgate, R.A., K. Aagaard, and T. Weingartner, Monthly temperature, salinity, and transport variability of the Bering Strait throughflow, Geophys. Res. Lett., 32, No. 4, L04601, doi:10.1029/2004GL021880, 2005. Woodgate, R.A., K. Aagaard, and T. Weingartner, A year in the physical oceanography of the Chukchi Sea: Moored measurements from autumn 1990-1991, Deep-Sea Res., II, 52, 3116-3149, doi:10.1016/j.dsr2.2005.1016, 2005. =============================================================================== For queries, please contact one of the following: Rebecca Woodgate woodgate@apl.washington.edu (206) 221-3268 Knut Aagaard aagaard@apl.washington.edu (206) 543-8942 Roger Andersen roger@apl.washington.edu (206) 543-1258 Polar Science Center, Applied Physics Lab, University of Washington 1013 NE 40th, Seattle, WA 98105-6698 USA FAX (206) 616-3142 =============================================================================== Meta data ========= 1) Platform: Subsurface oceanographic moorings 2) Project title: Western Arctic Shelf-Basin Interactions (SBI) Project 3) Data collection dates: July 2002 to September 2004 4) PIs: Knut Aagaard (aagaard@apl.washington.edu) Rebecca Woodgate (woodgate@apl.washington.edu) 5) Data collection method: Year-round moorings carrying - Aanderaa recording current meters (RCM-7) - Sea-Bird temperature/conductivity recorders (SBE-16) - RDI 300kHz Workhorse Acoustic Doppler Current Profilers (ADCP) 6) Data calibration method: Timestamps have been corrected for observed instrument clock drift. All times are given in GMT. For RCMs and SBEs, calibration coefficients are given in header file. RCMs: Pre and post calibrated by the manufacturer, by ESI, or at APL/UW. - pre-calibration used for data - as indicated in the headers, direction has been corrected by lookup table rather than fitted polynomial - direction corrected to true north, magnetic declination used is cited in the header SBEs: Pre and post calibrated by the manufacturer. - pre and post calibrations linearly time-weighted through the deployment. ADCPS: Tested by APL/manufacturer pre and post deployment. - compass calibrated as per manufacturer's specifications in Seattle prior to deployment. Estimated compass error is included in the header file. - direction corrected to true north, magnetic declination used is cited in the header. - data requiring speed of sound in water is corrected by the ADCP using the water temperature measured by the ADCP. - intensity of returned signals is not specially calibrated. 7) Instrumentation used: Aanderaa current meters RCM-7-sampling hourly. Sea-Bird SBE16 recorders, sampling at 60 min intervals as stated in headers. RDI 300 kHz ADCPS, recording ~ hourly (data averaged over the time interval) 8) Quality control procedures: Quality control variously provided by Knut Aagaard, Roger Andersen, Kay Runciman, and Rebecca Woodgate. SBE data have been despiked manually (cf., headers). In general, this was done conservatively, so some outliers almost certainly remain. RCM and SBE data checked against each other where possible. For SBI data, at times of rapid temperature change, the converted salinity record is very spikey - this is possibly just a sampling artefact. ADCP data rely on ADCP internal temperature for speed of sound corrections. ADCP Data files are included for all bins up to the surface although bins near the surface contain much larger errors (likely due to surface effects) and should be treated with caution. The following are the shallowest good bins last bin no errors last bin > 50 errors SBI3_02 - bin 14, ~ 18m bin 16, ~ 14m SBI3_03 - bin 17, ~ 12m bin 19, ~ 8m SBI4_02 - bin 8, ~ 34m bin 14, ~ 22m SBI4_03 - bin 15, ~ 20m bin 19, ~ 12m 9) Data format: RCM and SBE data - ASCII, format given in individual headers ADCP data - BINARY download file from ADCP and ASCII conversion of these files 10) Data collection problems: = On SBI3-02, the RCM (11456) carried a conductivity cell, which failed shortly after deployment, leaving the more accurate Sea-Birds as the only instruments recording conductivity (and salinity). = On SBI3-03, the ADCP 2232 is set with sampling interval of ~ 63 min. = On SBI4-03, ADCP 2332, bin 1 of the ADCP water data has unusually high errors. = Mooring SBI3-02 was dragged so time of last good record is inferred from data files. = On SBI4-03, SBE16 1700 appears to have inexplicably written one duplicate hourly record at 2003/278/2001. The duplicate has been removed before processing, resulting in a time record consistent with mooring recovery and final record times. 11) Other related data sets: There are two other SBI mooring data sets: Contact T. Weingartner, University of Alaska, Fairbanks. Two Chukchi Sea SBI moorings per year, one in Barrow Canyon, one in the Central Gap Contact R. Pickart, Woods Hole Oceanographic Institution. Eight Beaufort Slope SBI moorings per year, in a line at ~ 152°W, extending from ~ 71° 18'N to ~ 71°41'N. These mooring data sets are part of the larger SBI project, consisting of CTD, water sampling and biological data sets. For details, see http://arctic.bio.utk.edu/sbi/ and http://www.joss.ucar.edu/sbi 12) Conditions for use or citation: Data freely available Please, as a courtesy, contact the PIs before using these data 13) Data qualifications or warnings: See also Data collection problems. The temperature (T) and conductivity (C) recorded by a RCM are significantly less accurate than those recorded by a SBE. In most instances, a SBE was located very close to a RCM, so that the former would provide the record of choice for T and C even when the RCM measured both parameters. For data issues relevant to a specific deployment, see the individual headers. In general: RCM data: Standard Aanderaa limitations apply - estimated accuracy 2 cm/s in speed, 5° in direction, 0.05°C in temperature, >= 0.01 S/m in conductivity (corresponds to >= 0.2 psu in salinity). SBE data: Standard Sea-Bird limitations apply - estimated accuracy 0.02°C, 0.0012 S/m (corresponding to 0.02 psu), and <1 db. ADCP data: Standard RDI limitations apply - estimated accuracy > 0.5 cm/s in speed for water velocities (190 pings per ensemble) Estimated errors (given in the data files) vary with bin and time > 0.5 cm/s in speed for ice velocities (10 pings per ensemble) Estimated errors (given in the data files) vary with time < 1 deg in direction (see header files) range to ice only accurate to 1% of range to surface (i.e. ~ 0.5 m) Note of 8th Feb 2012, KNOWN PROBLEMS: - at least some of the processed ADCP Bottom track files have an error in calculating Uvel and Vvel from Speed and direction. In these files, Speed and Direction are correct, but Uvel and Vvel have been computed by subtracting, rather than adding the magnetic declination, and thus should be disregarded. 14) Grant numbers: These measurements have been conducted as part of the SBI studies, ONR Grant N00014-02-1-0305. 15) Sample repository locations: Joint Office for Science Support/UCAR (http://www.joss.ucar.edu/) (data also to be transfered to ADCC or NODC) University of Washington (http://psc.apl.washington.edu/HLD) =============================================================================== FILE LISTING ============= This archive contains 119 data files, i.e., = 1 readme file (this file) Readme_UW_SBI_ChukchiMoorings_2002to2004.txt = 4 RCM files e.g., SBI4_2003_RCM11454.txt = 6 SBE files e.g., SBI3_2002_SBE1397.txt The remaining 108 files relate to the 4 ADCPs. Specifically, there are: = 4 ADCP binary data files e.g., SBI4_2003_ADCP2332.000 = 4 ADCP ascii files of bottom track data e.g., SBI4_2003_02332.btm = 4 ADCP ascii files of instrument data e.g., SBI4_2003_02332.ins = 96 ADCP ascii files of water data e.g., SBI4_2003_02332_bin01.rdat The full file listing is: Name Size/bytes ========================== ========== Readme_UW_SBI_ChukchiMoorings_2002to2004.txt 20,506 SBI3_2002_02270.btm 2,394,142 SBI3_2002_02270.ins 1,214,967 SBI3_2002_02270_bin01.rdat 1,804,682 SBI3_2002_02270_bin02.rdat 1,804,682 SBI3_2002_02270_bin03.rdat 1,804,682 SBI3_2002_02270_bin04.rdat 1,804,682 SBI3_2002_02270_bin05.rdat 1,804,682 SBI3_2002_02270_bin06.rdat 1,804,682 SBI3_2002_02270_bin07.rdat 1,804,682 SBI3_2002_02270_bin08.rdat 1,804,682 SBI3_2002_02270_bin09.rdat 1,804,682 SBI3_2002_02270_bin10.rdat 1,804,682 SBI3_2002_02270_bin11.rdat 1,804,682 SBI3_2002_02270_bin12.rdat 1,804,682 SBI3_2002_02270_bin13.rdat 1,804,682 SBI3_2002_02270_bin14.rdat 1,804,682 SBI3_2002_02270_bin15.rdat 1,804,682 SBI3_2002_02270_bin16.rdat 1,804,682 SBI3_2002_02270_bin17.rdat 1,804,682 SBI3_2002_02270_bin18.rdat 1,804,682 SBI3_2002_02270_bin19.rdat 1,804,682 SBI3_2002_02270_bin20.rdat 1,804,682 SBI3_2002_02270_bin21.rdat 1,804,682 SBI3_2002_02270_bin22.rdat 1,804,682 SBI3_2002_02270_bin23.rdat 1,804,682 SBI3_2002_ADCP2270.000 8,491,871 SBI3_2002_RCM11456.txt 883,906 SBI3_2002_SBE1397.txt 797,662 SBI3_2003_02232.btm 2,000,562 SBI3_2003_02232.ins 1,015,733 SBI3_2003_02232_bin01.rdat 1,508,194 SBI3_2003_02232_bin02.rdat 1,508,194 SBI3_2003_02232_bin03.rdat 1,508,194 SBI3_2003_02232_bin04.rdat 1,508,194 SBI3_2003_02232_bin05.rdat 1,508,194 SBI3_2003_02232_bin06.rdat 1,508,194 SBI3_2003_02232_bin07.rdat 1,508,194 SBI3_2003_02232_bin08.rdat 1,508,194 SBI3_2003_02232_bin09.rdat 1,508,194 SBI3_2003_02232_bin10.rdat 1,508,194 SBI3_2003_02232_bin11.rdat 1,508,194 SBI3_2003_02232_bin12.rdat 1,508,194 SBI3_2003_02232_bin13.rdat 1,508,194 SBI3_2003_02232_bin14.rdat 1,508,194 SBI3_2003_02232_bin15.rdat 1,508,194 SBI3_2003_02232_bin16.rdat 1,508,194 SBI3_2003_02232_bin17.rdat 1,508,194 SBI3_2003_02232_bin18.rdat 1,508,194 SBI3_2003_02232_bin19.rdat 1,508,194 SBI3_2003_02232_bin20.rdat 1,508,194 SBI3_2003_02232_bin21.rdat 1,508,194 SBI3_2003_02232_bin22.rdat 1,508,194 SBI3_2003_02232_bin23.rdat 1,508,194 SBI3_2003_ADCP2232.000 7,094,081 SBI3_2003_RCM6493.txt 767,775 SBI3_2003_SBE0002.txt 697,377 SBI4_2002_02230.btm 2,401,380 SBI4_2002_02230.ins 1,218,736 SBI4_2002_02230_bin01.rdat 1,810,064 SBI4_2002_02230_bin02.rdat 1,810,064 SBI4_2002_02230_bin03.rdat 1,810,064 SBI4_2002_02230_bin04.rdat 1,810,064 SBI4_2002_02230_bin05.rdat 1,810,064 SBI4_2002_02230_bin06.rdat 1,810,064 SBI4_2002_02230_bin07.rdat 1,810,064 SBI4_2002_02230_bin08.rdat 1,810,064 SBI4_2002_02230_bin09.rdat 1,810,064 SBI4_2002_02230_bin10.rdat 1,810,064 SBI4_2002_02230_bin11.rdat 1,810,064 SBI4_2002_02230_bin12.rdat 1,810,064 SBI4_2002_02230_bin13.rdat 1,810,064 SBI4_2002_02230_bin14.rdat 1,810,064 SBI4_2002_02230_bin15.rdat 1,810,064 SBI4_2002_02230_bin16.rdat 1,810,064 SBI4_2002_02230_bin17.rdat 1,810,064 SBI4_2002_02230_bin18.rdat 1,810,064 SBI4_2002_02230_bin19.rdat 1,810,064 SBI4_2002_02230_bin20.rdat 1,810,064 SBI4_2002_02230_bin21.rdat 1,810,064 SBI4_2002_02230_bin22.rdat 1,810,064 SBI4_2002_02230_bin23.rdat 1,810,064 SBI4_2002_02230_bin24.rdat 1,810,064 SBI4_2002_02230_bin25.rdat 1,810,064 SBI4_2002_ADCP2230.000 9,537,791 SBI4_2002_RCM1926.txt 884,907 SBI4_2002_SBE0005.txt 800,350 SBI4_2002_SBE1226.txt 800,191 SBI4_2003_02332.btm 2,102,695 SBI4_2003_02332.ins 1,067,487 SBI4_2003_02332_bin01.rdat 1,594,221 SBI4_2003_02332_bin02.rdat 1,585,097 SBI4_2003_02332_bin03.rdat 1,585,097 SBI4_2003_02332_bin04.rdat 1,585,097 SBI4_2003_02332_bin05.rdat 1,585,097 SBI4_2003_02332_bin06.rdat 1,585,097 SBI4_2003_02332_bin07.rdat 1,585,097 SBI4_2003_02332_bin08.rdat 1,585,097 SBI4_2003_02332_bin09.rdat 1,585,097 SBI4_2003_02332_bin10.rdat 1,585,097 SBI4_2003_02332_bin11.rdat 1,585,097 SBI4_2003_02332_bin12.rdat 1,585,097 SBI4_2003_02332_bin13.rdat 1,585,097 SBI4_2003_02332_bin14.rdat 1,585,097 SBI4_2003_02332_bin15.rdat 1,585,097 SBI4_2003_02332_bin16.rdat 1,585,097 SBI4_2003_02332_bin17.rdat 1,585,097 SBI4_2003_02332_bin18.rdat 1,585,097 SBI4_2003_02332_bin19.rdat 1,585,097 SBI4_2003_02332_bin20.rdat 1,585,097 SBI4_2003_02332_bin21.rdat 1,585,097 SBI4_2003_02332_bin22.rdat 1,585,097 SBI4_2003_02332_bin23.rdat 1,585,097 SBI4_2003_02332_bin24.rdat 1,585,097 SBI4_2003_02332_bin25.rdat 1,585,097 SBI4_2003_ADCP2332.000 7,457,306 SBI4_2003_RCM11454.txt 771,903 SBI4_2003_SBE1541.txt 697,157 SBI4_2003_SBE1700.txt 697,347 ===============================================================================