README FILE FOR BERING STRAIT MOORING DATA 28th November 2012 ============================================================================= 12345678901234567890123456789012345678901234567890123456789012345678901234567 Bering Strait Moorings 2010-2011 This is an archive of data from US moorings deployed in the Bering Strait from summer 2010 to summer 2011. Moorings were also deployed for this period in Russian waters. This archive will be updated once these Russian data are available. Mooring deployments were funded by the NSF Arctic Observing Network (AON) award ARC-0855748 (PIs: Woodgate, Weingartner, Whitledge and Lindsay) with shiptime support from the NOAA RUSALCA (Russian-US Long Term Census of the Arctic) program. The mooring work required 2 dedicated cruises: - in 2010 (31st July - 11th August), a ~ 10 day cruise on the Russian vessel Khromov deployed the moorings. Some CTD sections were run on this cruise, and these data are archived separately. - in 2011 (12th - 23rd July), a ~ 10 day cruise on the Russian vessel Khromov recovered the moorings. Some CTD sections were run on this cruise, and these data are archived separately. (Note that this cruise also redeployed the moorings, under NSF-AON funding.) Cruise reports are included in this archive. For 2010 to 2011, a total of eight moorings were deployed: - three moorings (A1W, A1, A1E, also called A12,A11 and A13) in the Russian channel of the Strait - four moorings (A2W, A2, A4W, A4) in the US channel of the strait - one mooring (A3) at a site just north of the strait in US waters. In what follows, mooring names include a two digit suffix to represent year of deployment. Sites A1, A2, and A3 were established in 1990. A2 and A3 have been occupied almost continuously (all years except 96-97) since then. A1 was occupied for a few years from 1990,(90-91, 92-94) and then again since 2004. Site A4 was established in 2001. Sites A1E and A1W were established in 2005, and also carry Russian instrumentation not included in this archive (although documented in the cruise reports and here). Sites A2W and A4W were established in 2007. Mooring location A1 (also called A1-1) is in the middle of the western (Russian side) channel. Mooring location A1W (also called A1-2) is between A1 and the Russian coast. Mooring location A1E (also called A1-3) is between A1 and the Diomede Islands, which divide the strait. Mooring location A2 is in the middle of the eastern (Alaskan side) channel. Mooring location A3 is just north of the strait, immediately east of the Russian-US EEZ (Exclusive Economic Zone) line. Experience has shown that site A3 samples both eastern and western channel water. Mooring location A4 is close to the Alaskan coast and allows measurement of the Alaska Coastal Current. For an overview of previous and on-going Bering Strait mooring work, please see http://psc.apl.washington.edu/BeringStrait.html. Moorings carry a variety of instruments, listed in the table below. All records are year-round, sampling hourly or more frequently (Time Int. in table below). Data from instruments marked with * are not included in this archive. For access to these data, please contact the named PI in list below table. 12345678901234567890123456789012345678901234567890123456789012345678901234567 -------------------------------------------------------------------------- ID Deployed Latitude Longitude Instrument S/N Time Inst. Water in Year (N) (W) Int. Depth Depth -------------------------------------------------------------------------- A3-10 2010 66 19.61 168 57.93 ISCAT 5430 5min 17m 58m ISCAT-Logger 26 60min ... 58m 600kHz-ADCP 2144 30min 44m 58m SBE37 Microcat 4510 15min 44m 58m A2W-10 2010 65 48.07 168 47.90 ISCAT 5472 5min 19m 53m ISCAT-Logger 23 30min ... 53m 300kHz-ADCP 2269 30min 44m 53m SBE16 1400 60min 48m 53m FLTUSBWetlabs* 932 48m 53m WhaleRecorder* 129 48m 53m A2-10 2010 65 46.87 168 34.05 ISCAT 5470 NR 19m 56m ISCAT-Logger 7 30min ... 56m 300kHz-ADCP 1495 30min 45m 56m SBE16woptic 4973 60min 48m 56m ISUS* 087 - 48m 56m A4W-10 2010 65 45.42 168 21.97 ISCAT 7622 5min 20m 55m ISCAT-Logger 21 30min ... 55m 300kHz-ADCP 2230 30min 43m 55m SBE16 2341 60min 45m 55m A4-10 2010 65 44.76 168 15.76 ISCAT 5471 5min 19m 49m ISCAT-Logger 22 30min ... 49m 300kHz-ADCP 2234 30min 39m 49m SBE16 8 60min 41m 49m FLTUSBWetlabs* 935 41m 49m SBE26p-BPG 1175 30min 47m 49m -------------------------------------------------------------------------- Depths are estimated from mooring design and pressure sensors where available, and are good to 1-2m. NR=instrument not recovered ND=No data Instruments with data included here: 300KHz-ADCP - 300kHz RDI/Teledyne Workhorse Acoustic Doppler Current Profiler 600KHz-ADCP - 600kHz RDI/Teledyne Workhorse Acoustic Doppler Current Profiler SBE37 Microcat - Seabird SBE 37 Temperature Salinity Pressure recorder SBE16woptic - Seabird SBE16plus with optical data (including some or all of fluorescence, turbidity, transmissivity and PAR) - see headers SBE26p-BPG - Seabird SBE26plus Bottom Pressure Gauge RCM9Turb - Aanderaa RCM9 acoustic current meter with turbidity sensor RCM9LW - Aanderaa Lightweight RCM9 acoustic current meter Instruments with data not included here: AARI-CM&CTD - Current meter and CTD from AARI (Arctic and Antarctic Research Institute, Russia), PI: Igor Lavrenov, AARI ISUS - ISUS Nitrate sensor, PI: Terry Whitledge, UAF WhaleRecorder - Passive Acoustic Whale recorder, PI: Kate Stafford, UW FLTUSBWetlabs - Wetlabs self-contained Fluoresence/Turbidity instrument, PI: Rebecca Woodgate, UW Each data file contains the data from one instrument-year - the listed year in the mooring name is the year in which the mooring was deployed. Turbidity, fluorometer and PAR data from the RCM and SBE instruments are included in this archive, although only minimal quality control of the data has been performed. In this form of the data, these channels are recorded only as external voltage, as calibration data was unavailable. For calibration data, please contact Tom Weingartner, UAF. The SBE16plus BPG also recorded wave burst data - this may be extracted from the .hex files included in this archive, but has not been processed here. For RCMs and SBEs, calibrated data are recorded in one file per instrument per year, with naming convention: BeringStrait_yyyy_ID_III_#####.ttt yyyy=Deployment year; ID=mooring ID; III=instrument type; #####=serial number; ttt=indicates calibration, with .pre=pre-deployment calibration used, .ppp=pre and post deployment calibrations merged. The SBE-16 and 26 hexidecimal files (unaltered from the download) are also included, indicated by extension .hex. For the ADCPs, there are multiple files per instrument. BeringStrait_yyyy__ID_#####ADCPraw.000 = Binary download from the ADCP (note there are sometimes two files for the ADCP - see notes below) BeringStrait_yyyy__ID_#####_ADCPrecovery.txt = post deployment tests The remainder are ASCII conversions of the data, corrected for clock drift and magnetic declination. BeringStrait_yyyy__ID_#####.btm = ASCII bottom track data (including ice range and velocity) BeringStrait_yyyy__ID_#####.ins = ASCII instrument data (e.g. heading, pitch, roll, temperature) BeringStrait_yyyy__ID_#####_bin01.rdat = ASCII water velocity data in Bin 1 BeringStrait_yyyy__ID_#####.bin02.rdat = ASCII water velocity data in Bin 2 etc. (Bin depths are given in the data files) BeringStrait_yyyy__ID_#####mbin01.rdat = ASCII data from re-averaged Bin 1 BeringStrait_yyyy__ID_#####mbin02.rdat = ASCII data from re-averaged Bin 2 etc. (Bin depths are given in the data files) Header information is included in each data file. ----------------------------------------------------------------------------- For details of the measurements and their interpretation, please see: Woodgate, R.A., and K. Aagaard (2005) Revising the Bering Strait freshwater flux into the Arctic Ocean, Geophys. Res. Lett., 32, L02602, doi:10.1029/2004GL021747. Woodgate, R.A., K. Aagaard, and T. Weingartner (2005) Monthly temperature, salinity, and transport variability of the Bering Strait throughflow, Geophys. Res. Lett., 32, No. 4, L04601, doi:10.1029/2004GL021880. Woodgate, R. A., K. Aagaard, and T. J. Weingartner (2005) A year in the physical oceanography of the Chukchi Sea: Moored measurements from autumn 1990-1991,Deep-Sea Res., Part II, 52, 3116-3149, doi: 10.1016/j.dsr2.2005.10.016. Woodgate, R. A., K. Aagaard, and T. J. Weingartner (2006) Interannual changes in the Bering Strait fluxes of volume, heat and freshwater between 1991 and 2004, Geophys. Res. Lett., 33, L15609, doi:10.1029/2006GL026931. Aagaard, K., T.J.Weingartner, S.L. Danielson, R.A. Woodgate, G.C.Johnson, T.E.Whitledge (2006), Some controls on flow and salinity in Bering Strait, Geophys. Res. Lett., 33, L19602, doi:10.1029/2006GL026612. Woodgate, R. A., T. Weingartner, and R. Lindsay (2010), The 2007 Bering Strait oceanic heat flux and anomalous Arctic sea-ice retreat, Geophys. Res. Lett., 37, L01602, doi:10.1029/2009GL041621. Woodgate, R. A., T. Weingartner, and R. Lindsay (2012), Observed increases in Bering Strait oceanic fluxes from the Pacific to the Arctic from 2001 to 2011 and their impacts on the Arctic Ocean water column Geophys. Res. Lett., in press. For an overview, please see: http://psc.apl.washington.edu/BeringStrait.html For queries, please contact: Rebecca Woodgate woodgate@apl.washington.edu (206) 221-3268 Polar Science Center, Applied Physics Lab, University of Washington 1013 NE 40th, Seattle, WA 98105-6698 USA FAX (206) 543-6785 ------------------------------------------------------------------------------ Meta data ========= 1) Platform: Subsurface oceanographic moorings 2) Project title: Bering Strait 3) Data collection dates: summer 2010 to summer 2011 4) PI: Rebecca Woodgate (woodgate@apl.washington.edu) Tom Weingartner (weingart@ims.uaf.edu) 5) Data collection method: Year-round moorings carrying - Aanderaa recording current meters (RCM) - Sea-Bird temperature/conductivity and pressure recorders (SBE) - RDI 300kHz Workhorse Acoustic Doppler Current Profilers (ADCP) 6) Data calibration method: Unless noted otherwise in the header on each data file, 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: - Predeployment calibrated by the manufacturer (AA), - pre-calibration used for data reduction. - where 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 - RCM9 data has been corrected for the temperature/pressure variability of the speed of sound using temperature data from the RCM SBEs: - Generally pre and post calibrated by the manufacturer (indicated by suffix .ppp) - pre and post calibrations linearly time-weighted through the deployment. - .pre suffix indicates only pre-cruise calibration used ADCPS: Tested by APL/UAF/manufacturer pre deployment. - A2W, A2, A4W, A4 compasses calibrated as per manufacturer's specifications in Seattle prior to deployment. Estimated compass error is included in the header file - A1 and A3 ADCPs may have batteries exchanged at sea and thus compass calibration may be poor - see headers - where available, at sea compass check also included in 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: (see table for sampling frequencies) Aanderaa current meters RCM-9 (one with optics sensor) Sea-Bird SBE26plus recorders Sea-Bird SBE16 recorders Sea-Bird SBE16plus recorders with optics sensors Sea-Bird SBE37 recorders ISCAT loggers (SBE37 Microcat logging data to an APL-Logger) RDI 300 and 600 kHz Workhorse ADCP - bin size either 2m or 1m. (if the latter, .000 data is at original bin size, and extracted data averaged onto 2m bins). 8) Quality control procedures: Quality control provided by Rebecca Woodgate. RCM and SBE data checked against each other where possible. RCM-9 measurements of water velocity depend on the speed of sound in water. The manufacturer's default is to assume a sound speed of 1500 m/s. In data processing, we use RCM temperature and mooring information of instrument depth to obtain a more accurate speed of sound at the RCM during deployment, and thus recompute the water velocity (Cor Speed). SBE optical data is not quality controlled and should be treated with caution. ADCP data rely on ADCP internal temperature for speed of sound corrections. ADCP on A1 and A3 recorded in 1m bins. This archive contains the original binary file of this data (without correction for magnetic declination). For the ascii files in this archive (which are corrected for magnetic declination), these data are averaged onto 2m bins to match other deployments. 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. 9) Data format: RCM and SBE data - ASCII, format given in individual headers (uncalibrated "hex" data also included for SBE16s and SBE26p) ADCP data - 2 formats: a) BINARY download file from ADCP and b) ASCII conversion of these files (in 2m bins) 10) Data collection problems: By Mooring: - the 2010-2011 moorings were biofouled on recovery (photographs included in archive) Optics data is likely contaminated by this biofouling and should be treated with caution. - Mooring A3-10 did not released properly and required dragging. This is noted in the headers, and the release time is the time the mooring was sighted on the surface By Instrument: === SBE26p (Bottom Pressure Gauge and Wave Recorder) A410_1175 - .hex files contain unprocessed wave burst data - converted pressure data show no obvious problems === SBE16 (no optics) A2W10_1400 - light biofouling, cell clear on recovery - 0.05 psu salinity difference pre-post calibrations A4W10_2341 - light biofouling, cell clear on recovery - 0.07 psu salinity difference pre-post calibrations - 7 temperature spikes removed A410_0008 - heavy biofouling, but cell mostly clear on recovery - 0.09 psu salinity difference pre-post calibrations === SBE16Plus (with optics) Note - none of optics data is quality controlled. Uncalibrated (.hex) files included in archive A210_4973 - with biowiper - moderate biofouling, but cell clear - instrument deployed horizontally (perhaps trapping sediment in cell, but comparison to other SBEs in array suggests no ill effects) - optics calibrations unavailable, external voltages included here. === SBE37s (non-ISCAT) A310_4510 - only precal available - one suspected low salinity spike === ISCATS (Loggers and SBE37s) A310 - SBE37 5430 - recovered with full record - pre-post drift ~ 0.03 psu - Logger - stopped in Oct 2010 A2W10 - SBE37 5472 - recovered with full record - pre-post drift ~ 0.03 psu - Logger - 6 spikes removed A210 - SBE37 - lost ~ 18hrs before recovery - Logger - data ok A4W10 - SBE37 7622 - recovered with full record - pre-post drift ~ 0.06 psu - Logger - stopped in Dec 2010 A410 - SBE37 5471 - recoverd with full record - pre-post drift ~ 0.05 psu - ~ 10min clock discrepancy with in water times - Logger - data ok === ADCPs Note that ADCP range measurements are not corrected for pitch and roll. For full discussion and correction, see: Woodgate and Holroyd, 2011, included in archive. A310_adcp2144 (600kHz) - bin 1 has high velocity errors - wrote 2 files, missing 1 record indicated with 9999 - erroneous temperature sensor for start of record introduces 2-13% error in early velocities (see header). - originally 1m data, reaveraged to 2m bins - compass calibration error may be up to 10deg A2W10_adcp2269 - bins 1 and 2 have high velocity errors - bins 8 and 9 have high velocity errors likely from iscat A210_adcp1495 - bin 1 has high velocity errors A4W10_adcp2230 - bin 1 has high velocity errors - bin 9 has high velocity errors likely from iscat - instrument leaked just before or at recovery A410_adcp2234 - bin 1 has high velocity errors - bin 7 has high velocity errors likely from iscat Photographic documentation of biofouling on recovery is available via cruise reports, included here and on the Bering Strait website: http://psc.apl.washington.edu/BeringStrait.html. 11) Other related data sets: This data set is a continuation of mooring measurements made in the Bering Strait almost continuously since 1990. Mooring data have already been archived via the SBI project, managed by JOSS/EOS, and at NODC. For details see http://psc.apl.washington.edu/BeringStrait.html http://www.eol.ucar.edu/projects/sbi/ http://sbi.utk.edu/ http://www.nodc.noaa.gov Since 2000, CTD sections have been run in the Bering Strait on the mooring cruises. This data is also accessible via the http links above. 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 deg in direction, 0.05 deg 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 deg C, 0.0012 S/m (corresponding to 0.02 psu), and < 1 db. - see header files for difference between pre and post calibration SBE26plus data: Standard Sea-Bird limitation apply - estimated accuracy 0.01 deg C, 0.01% of full scale (for these deployments, range 60db, thus accuracy 0.006db) ADCP data: Standard RDI limitations apply - estimated accuracy ~ 0.5 cm/s for water velocities (~100 pings per ensemble) Estimated errors (given in the files) vary with bin and time ~ 1 cm/s for ice velocities (2 or 5 pings per ensemble) Estimated errors (given in the files) vary with time ~ 1 deg in direction (see header files) Range to ice - accurate to 1% of range to surface (i.e. ~ 0.4 m) ~ 0.4 deg C in temperature Optical Sensor Data: These unmodified records are included, although no quality control of the data has been performed, as noted in the header files. This leaves final judgments about record quality to the user. 14) Grant numbers: Mooring sponsorship came from - NSF Polar Programs Arctic Observing Network ARC-0855748 (PIs: Woodgate, Weingartner, Whitledge and Lindsay) with shiptime support from - NOAA Arctic Research RUSALCA - Russian-US Longterm Census of the Arctic: http://www.arctic.noaa.gov/aro/russian-american/ 15) Sample repository locations: National Ocean Data Center (http://www.nodc.noaa.gov) University of Washington (http://psc.apl.washington.edu/HLD) ============================================================================== FILE LISTING ============= Total number of files: Main directory: 29 files and 5 subdirectories Size (b) Name ------- ---- = Metadata file (1 file) Bering_Strait_Moorings_NSFAONRusalca_10to11_ReadMe.txt = cruise reports (2 files) and technical note (1 file) CruiseReportKhromov2010wEL_verNov11.pdf Khromov2011CruiseReportwithEL_Oct2011.pdf WoodgateandHolroyd2011_BTrangeCorrection.pdf = photos of biofouling on recovery (5 files) BeringStrait_A210_RecoveryPhotos.jpg BeringStrait_A2W10_RecoveryPhotos.jpg BeringStrait_A410_RecoveryPhotos.jpg BeringStrait_A4W10_RecoveryPhotos.jpg BeringStrait_A310_RecoveryPhotos.jpg = SBE26plus - Bottom Pressure and Wave Recorder (2 files) - 1 .hex files of raw data - 1 .ppp files of pre-post calibrated Pressure and Temp (see below for processing software) BeringStrait_2010_A4_sbe26p_1175.hex BeringStrait_2010_A4_sbe26p_1175.ppp = SBE16 (6 files) - 3 .hex files of raw data - 3 .ppp files of pre-post calibrated data BeringStrait_2010_A2W_sbe16_1400.hex BeringStrait_2010_A4W_sbe16_2341.hex BeringStrait_2010_A4_sbe16_0008.hex BeringStrait_2010_A2W_sbe16_1400.ppp BeringStrait_2010_A4W_sbe16_2341.ppp BeringStrait_2010_A4_sbe16_0008.ppp = SBE16plus with optics (2 files) - 1 .hex files of raw data - 1 .pre files of pre calibrated data BeringStrait_2010_A2_sbe16opt_4973.hex BeringStrait_2010_A2_sbe16opt_4973.pre = SBE37 Microcat (1 files) BeringStrait_2010_A3_sbe37_4510.pre = ISCAT data (9 files) - 5 ICLog*.pre of pre calibrated logger data - 4 ICsbe37*.ppp pre-post calibrated SBE37 data BeringStrait_2010_A2W_ICLog23_5472.pre BeringStrait_2010_A2_ICLog07_5470.pre BeringStrait_2010_A3_ICLog26_5430.pre BeringStrait_2010_A4W_ICLog21_7622.pre BeringStrait_2010_A4_ICLog22_5471.pre BeringStrait_2010_A2W_ICsbe37_5472.ppp BeringStrait_2010_A3_ICsbe37_5430.ppp BeringStrait_2010_A4W_ICsbe37_7622.ppp BeringStrait_2010_A4_ICsbe37_5471.ppp ... and the 5 subdirectories of ADCP data: == BeringStrait_2010_A3_adcp2144 == BeringStrait_2010_A2W_adcp2269 == BeringStrait_2010_A2_adcp1495 == BeringStrait_2010_A4W_adcp2230 == BeringStrait_2010_A4_adcp2234 Files within each data subdirectories: == - one or more .000 file (original download, sometimes in parts) - predeployment test file - recovery test file - one .btm file - bottom track data - one .ins file - instrument data - several .rdat file - data in each ADCP bin