README FILE FOR BERING STRAIT MOORING DATA 14 July 2005 ====================================================================================== Bering Strait Moorings 1990-2002 This is an archive of data from moorings deployed in Bering Strait from autumn 1990 to summer 2002, with annual replacement of moorings. Only during the field year 1996-97 were there no measurements. Mooring sponsorship came variously from NOAA, NSF, or ONR, depending on the year. Bering Strait is divided into two channels by the Diomede Islands, which are separated by the Russia-U.S. Exclusive Economic Zone (EEZ) boundary. This political divide requires specific permission to work in the western channel of the strait, something we have been able to obtain during only a few years. Mooring location A1 is in the middle of the western (Siberian side) channel, while location A2 is in the middle of the eastern (Alaskan side) channel. Mooring location A3 is approximately 30 nm north of the Diomede Islands, and less than 1 nm east of the EEZ line. Experience has shown that this location samples both eastern and western channel water. For the 1992-1994 mooring deployments, the northern mooring, re-named A3north, was moved to a location about 150 nm north of Bering Strait. The recent addition of mooring location A4 in the eastern channel close to the Alaskan coast allows measurement within the intensified Alaskan coastal flow, with its burden of freshwater. Sill depth in the two Bering Strait channels is approximately 50-55 m. These moorings typically mounted an Aanderaa RCM current meter 5-10 m above the bottom and a Sea-Bird Temperature-Conductivity recorder 1 m deeper. They were replaced annually in late summer, so that each file contains the data from one instrument-year. The listed year is the year that particular mooring was deployed. Some moorings were equipped with an upward looking sonar, but the ULS data are not included in this archive. Each instrument, Sea-Bird or Aanderaa, is represented by a single ASCII file, with calibration, position, and other supporting data in the header. Mooring Year - Latitude Longitude Instrument S/N Instrument Water Depth Depth A1 1990 - 65° 54.00' N 169° 25.66' W - RCM-4 1823 - 41m 50m A1 1990 - 65° 54.00' N 169° 25.66' W - SBE-16 521 - 42m 50m A2 1990 - 65° 46.48' N 168° 35.23' W - RCM-4 5258 - 44m 53m A2 1990 - 65° 46.48' N 168° 35.23' W - SBE-16 539 - 45m 53m A3 1990 - 66° 17.58' N 168° 57.89' W - RCM-4 1029 - 47m 56m A3 1990 - 66° 17.58' N 168° 57.89' W - SBE-16 516 - 48m 56m A2 1991 - 65° 46.55' N 168° 36.17' W - RCM-4 3221 - 45m 53m A3 1991 - 66° 17.68' N 168° 58.73' W - RCM-4 6557 - 46m 54m A1 1992 - 65° 53.62' N 169° 26.08' W - RCM-4 6201 - 46m 52m A1 1992 - 65° 53.62' N 169° 26.08' W - SBE-16 11 - 47m 52m A2 1992 - 65° 46.51' N 168° 36.14' W - RCM-4 6493 - 49m 55m A3north 1992 - 68° 09.97' N 168° 58.48' W - RCM-4 6919 - 47m 57m -A3north for the 1992 mooring year was about 120 nm north of the usual A3 position. A1 1993 - 65° 53.55' N 169° 26.19' W - RCM-4 6498 - 42m 48m A1 1993 - 65° 53.55' N 169° 26.19' W - SBE-16 749 - 43m 48m A2 1993 - 65° 46.49' N 168° 35.14' W - RCM-4 6543 - 46m 54m A2 1993 - 65° 46.49' N 168° 35.14' W - SBE-16 1223 - 47m 54m A3north 1993 - 68° 09.92' N 168° 56.56' W - RCM-4 6544 - 50m 56m A3north 1993 - 68° 09.92' N 168° 56.56' W - SBE-16 750 - 51m 56m -A3north for the 1993 mooring year was about 120 nm north of the usual A3 position. A2 1994 - 65° 46.56' N 168° 35.41' W - RCM-7 11456 - 48m 54m A2 1994 - 65° 46.56' N 168° 35.41' W - SBE-16 1698 - 49m 54m A3north 1994 - 68° 10.20' N 168° 58.35' W - RCM-7 11458 - 52m 59m A3north 1994 - 68° 10.20' N 168° 58.35' W - SBE-16 1699 - 53m 59m -A3north for the 1994 mooring year was about 120 nm north of the usual A3 position. A2 1995 - 65° 46.56' N 168° 35.45' W - RCM-7 IMS2 - 45m 52m A2 1995 - 65° 46.56' N 168° 35.45' W - SBE-16 1443 - 47m 52m A2 1997 - 65° 46.51' N 168° 35.10' W - RCM-7 6544 - 48m 54m A2 1997 - 65° 46.51' N 168° 35.10' W - SBE-16 8 - 49m 54m A3 1997 - 66° 17.60' N 168° 57.87' W - RCM-7 9513 - 52m 58m A3 1997 - 66° 17.60' N 168° 57.87' W - SBE-16 1408 - 53m 58m A2 1998 - 65° 46.71' N 168° 34.90' W - SBE-16 2 - 50m 55m A3 1998 - 66° 17.69' N 168° 58.11' W - RCM-7 IMS5 - 54m 59m A3 1998 - 66° 17.69' N 168° 58.11' W - SBE-16 4 - 55m 59m A2 1999 - 65° 46.71' N 168° 34.75' W - RCM-7 6546 - 46m 55m A2 1999 - 65° 46.71' N 168° 34.75' W - SBE-16 1225 - 47m 55m A3 1999 - 66° 19.71' N 168° 58.10' W - RCM-7 11135 - 49m 58m A3 1999 - 66° 19.71' N 168° 58.10' W - SBE-16 8 - 50m 58m A2 2000 - 65° 46.73' N 168° 34.77' W - RCM-7 11423 - 46m 55m A2 2000 - 65° 46.73' N 168° 34.77' W - SBE-16 1224 - 47m 55m A3 2000 - 66° 19.66' N 168° 58.00' W - RCM-7 11459 - 51m 58m A3 2000 - 66° 19.66' N 168° 58.00' W - SBE-16 4 - 52m 58m A2 2001 - 65° 46.76' N 168° 34.52' W - SBE-16 2 - 49m 56m A3 2001 - 66° 19.58' N 168° 58.03' W - RCM-9 523 - 50m 57m A3 2001 - 66° 19.58' N 168° 58.03' W - SBE-16 1541 - 51m 57m A4 2001 - 65° 44.73' N 168° 15.83' W - RCM-7 1923 - 41m 48m A4 2001 - 65° 44.73' N 168° 15.83' W - SBE-16 7 - 42m 48m -------------------------------------------------------------------------------------- For details of the 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. 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., accepted for publication. For an overview, please see: http://psc.apl.washington.edu/BeringStrait.html For queries, please contact one of the following: Knut Aagaard aagaard@apl.washington.edu (206) 543-8942 Rebecca Woodgate woodgate@apl.washington.edu (206) 221-3268 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: Various, depending on year 3) Data collection dates: autumn 1990 to summer 2002 4) PIs: Knut Aagaard (aagaard@apl.washington.edu) Rebecca Woodgate (woodgate@apl.washington.edu) 5) Data collection method: Aanderaa recording current meters (RCM) Sea-Bird temperature/conductivity recorders (SBE) 6) Data calibration method: Calibration coefficients in header for each data file RCMs: Pre- and post-calibrated by the manufacturer, by ESI, at NOAA/PMEL, or at APL/UW. - pre-calibration used for data - as noted in the headers, paddlewheel and Savonius speed rotors have been calibrated with differing coefficients in these data. - 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 SBEs: Pre and post calibrated by the manufacturer. - pre and post cals linearly time-weighted through the deployment. 7) Instrumentation used: Aanderaa current meters RCM4, RCM7, or RCM9 sampling hourly Sea-Bird SBE16 recorders, sampling at 30 or 60 min intervals as stated in headers 8) Quality control procedures: Quality control variously provided by Knut Aagaard, Roger Andersen, Clark Darnall, Andrew Roach, and Kay Runciman. 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. 9) Data format: ASCII, format given in individual headers 10) Data collection problems: Rotor fouling is an ongoing problem in Bering Strait. For example, the speeds at A1 and A2 during the 1990-91 deployment are not reliable during the last ca.160 days of the record (compare to the A3 record, which does not appear to be impaired by fouling; also cf., Roach et al., 1995; Woodgate et al., accepted for publication). Other instrumental records are curtailed in time because of instrument failures. These, as well as various sensor problems, can be pursued through the header information in the individual files for each instrument. 11) Other related data sets: This data set constitutes a comprehensive stand-alone time series view of Bering Strait extending over more than a decade. Portions of this data set have previously been submitted for archiving as follows: - The 1993-94 and 1994-95 records from A1, A2, and A3 were submitted to the National Snow and Ice Data Center (NSIDC at http://nsidc.org/) in January 1997 as part of a larger data set extending from Bering Strait into the northern Chukchi Sea (Investigations of the Western Arctic: Transport and water properties in Bering Strait and over the Chukchi shelf). At the request of the Arctic Data Coordination Center (ADCC), the data were re-submitted in February 2002. - The 1990-91 records from A1, A2, and A3 were submitted to the Joint Office for Science Support (JOSS at http://www.ofps.ucar.edu/arcss/) in April 2004 as part of a larger data set extending from Bering Strait through the Chukchi Sea (Chukchi90 MOORING DATA). 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: 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. 14) Grant numbers: Various, depending on the year, with support from NOAA, NSF, or ONR. Beginning in 1999, the measurements have been conducted as part of the SBI studies, grant N00014-99-1-0345. 15) Sample repository locations: Not applicable. ====================================================================================== FILE LISTING ============= - 44 data files - 1 readme file (this file) = Bering_Strait_Moorings_1990-2001_ReadMe.txt Name Size/bytes ========================================= ========== BeringStrait_1990_A1_rcm1823.txt 605,628 BeringStrait_1990_A1_sbe521.txt 619,090 BeringStrait_1990_A2_rcm5258.txt 627,397 BeringStrait_1990_A2_sbe539.txt 636,226 BeringStrait_1990_A3_rcm1029.txt 608,584 BeringStrait_1990_A3_sbe516.txt 637,178 BeringStrait_1991_A2_rcm3221.txt 405,393 BeringStrait_1991_A3_rcm6557.txt 405,892 BeringStrait_1992_A1_rcm6201.txt 411,059 BeringStrait_1992_A1_sbe11.txt 650,522 BeringStrait_1992_A2_rcm6493.txt 411,094 BeringStrait_1992_A3north_rcm6919.txt 93,618 BeringStrait_1993_A1_rcm6498.txt 445,595 BeringStrait_1993_A1_sbe749.txt 664,585 BeringStrait_1993_A2_rcm6543.txt 440,341 BeringStrait_1993_A2_sbe1223.txt 1,329,186 BeringStrait_1993_A3north_rcm6544.txt 445,701 BeringStrait_1993_A3north_sbe750.txt 666,559 BeringStrait_1994_A2_rcm11456.txt 484,696 BeringStrait_1994_A2_sbe1698.txt 1,352,279 BeringStrait_1994_A3north_rcm11458.txt 470,322 BeringStrait_1994_A3north_sbe1699.txt 1,246,610 BeringStrait_1995_A2_rcmIMS2.txt 638,648 BeringStrait_1995_A2_sbe1443.txt 630,203 BeringStrait_1997_A2_rcm6544.txt 416,178 BeringStrait_1997_A2_sbe8.txt 655,729 BeringStrait_1997_A3_rcm9513.txt 416,359 BeringStrait_1997_A3_sbe1408.txt 655,093 BeringStrait_1998_A2_sbe2.txt 1,309,368 BeringStrait_1998_A3_rcmIMS5.txt 986,958 BeringStrait_1998_A3_sbe4.txt 1,512,519 BeringStrait_1999_A2_rcm6546.txt 942,705 BeringStrait_1999_A2_sbe1225.txt 724,318 BeringStrait_1999_A3_rcm11135.txt 942,617 BeringStrait_1999_A3_sbe8.txt 725,469 BeringStrait_2000_A2_rcm11423.txt 788,820 BeringStrait_2000_A2_sbe1224.txt 1,336,252 BeringStrait_2000_A3_rcm11459.txt 788,394 BeringStrait_2000_A3_sbe4.txt 1,336,801 BeringStrait_2001_A2_sbe2.txt 518,995 BeringStrait_2001_A3_rcm523.txt 572,605 BeringStrait_2001_A3_sbe1541.txt 519,066 BeringStrait_2001_A4_rcm1923.txt 610,371 BeringStrait_2001_A4_sbe7.txt 518,918 ======================================================================================