Metadata: Identification_Information: Citation: Citation_Information: Originator: Mr. Patrick Caldwell Publication_Date: Unpublished material Title: Ocean currents measured by shipboard ADCP from global oceans-- the Joint Archive for Shipboard ADCP holdings acquired between April 2006 and November 2007 Online_Linkage: http://ilikai.soest.hawaii.edu/sadcp/ Description: Abstract: Absolute U- and V-component ocean current vectors from Shipboard Acoustic Doppler Current Profilers (SADCP), as both a high frequency sampling (nominally 5 minutes with 8 m depth bins) and an averaged subset (hourly time and 10 m depth means), are provided for the global oceans. The depth range is typically from 20 to 300 m although recent technology has allowed penetration to over 1 km. The high frequency samples along with ancillary parameters are provided in the Common Oceanographic Data Assess System (CODAS) binary format. The standard (averaged) subset is stored in ASCII. This dataset represents the cruises acquired from April 2006 through November 2007 at the Joint Archive for SADCP, a collaboration of NOAA and the E.Firing ADCP Laboratory at the University of Hawaii. The data have been contributed by both US and international organizations. A total of 78 cruises on 12 ships (1.1 gigabytes) are included. Purpose: Provide an archive of absolute ocean current data for global oceans. Supplemental_Information: NOAASupplemental: Entry_ID: Unknown Sensor_Name: ADCP, GPS Source_Name: R/V Hi_Ialakai R/V Ka`imi`moana R/V Kaiyo R/V Knorr R/V Laurence_M_Gould R/V Melville R/V Nathaniel_B._Palmer R/V New_Horizon R/V Oscar_Elton_Sette R/V Roger_Revelle R/V Ron_Brown R/V Thomas_G._Thompson Project_Campaign: Joint Archive for Shipboard ADCP Storage_Medium: CODAS and ASCII Online_size: 1.1 Gbytes Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19990913 Ending_Date: 20070428 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: Annually Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -180.0 East_Bounding_Coordinate: 180.0 North_Bounding_Coordinate: 55.0 South_Bounding_Coordinate: -70.0 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: ocean currents Theme_Keyword: shipboard acoustic doppler current profilers (ADCP) Theme_Keyword: R/V Hi_Ialakai Theme_Keyword: R/V Ka`imi`moana Theme_Keyword: R/V Kaiyo Theme_Keyword: R/V Knorr Theme_Keyword: R/V Laurence_M_Gould Theme_Keyword: R/V Melville Theme_Keyword: R/V Nathaniel_B._Palmer Theme_Keyword: R/V New_Horizon Theme_Keyword: R/V Oscar_Elton_Sette Theme_Keyword: R/V Roger_Revelle Theme_Keyword: R/V Ron_Brown Theme_Keyword: R/V Thomas_G._Thompson Place: Place_Keyword_Thesaurus: None Place_Keyword: global oceans Place_Keyword: Pacific Place_Keyword: Atlantic Place_Keyword: Indian Place_Keyword: Southern Ocean Stratum: Stratum_Keyword_Thesaurus: None Stratum_Keyword: upper ocean (< 1500 m) Access_Constraints: None Use_Constraints: data set credit required Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Mr. Patrick Caldwell Contact_Organization: NOAA/NESDIS/NODC/NCDDC Hawaii Liaison Office Contact_Address: Address_Type: mailing and physical Address: 1000 Pope Rd. MSB 316 City: Honolulu State_or_Province: HI Postal_Code: 96822 Country: USA Contact_Voice_Telephone: 808-956-4105 Contact_Facsimile_Telephone: 808-956-4105 Contact_Electronic_Mail_Address: patrick.caldwell@noaa.gov Hours_of_Service: 7 AM to 4 PM Contact_Instructions: email best option Data_Set_Credit: NOAA/NESDIS/NODC/NCDDC Hawaii Liaison Office, Joint Archive for Shipboard ADCP(NOAA/Univ. of Hawaii) Native_Data_Set_Environment: ASCII and CODAS (binary) Data_Quality_Information: Logical_Consistency_Report: complete Completeness_Report: Cruises acquired prior to April 2006 were submitted to the NODC in previous years. The present dataset only includes cruises received and ingested into the JASADCP between April 2006 and November 2007 Lineage: Process_Step: Process_Description: Shipboard ADCP Data Collection Methodology. The hull-mounted ADCP estimates horizontal and vertical velocity as a function of depth by using the Doppler effect to measure the radial relative velocity between the instrument and scatterers in the ocean. Three acoustic beams in different directions are the minimal requirement for measuring the three velocity components. A fourth beam adds redundancy and an error estimate. The ADCP transmits a ping from each transducer element roughly once per second. The echo arrives back at the instrument over an extended period, with echos from shallow depths arriving sooner than ones from greater ranges. Profiles are produced by range-gating the echo signal, which means the echo is broken into successive segments called depth bins which correspond to successively deeper depth ranges. The operator configures the length of each depth bin and the transmit pulse, which determines the degree of averaging in the vertical, depending on whether one is interested more in vertical resolution or profile penetration. The noisy velocity estimates from each ping are vector-averaged into 1- to 10-minute ensembles. The relative velocities are rotated from the transducer's to the earth's reference frame using the ship's gyrocompass. Finally, relative velocities and various ancillary parameters are stored on the ship using a data acquisition system (DAS) which also optionally records navigation information, such as provided by the GPS. Specifics of the instrument capabilities and configuration options are well documented (RDI, 1989).RD Instruments, 1989. Acoustic Doppler Current Profilers Principles of Operation: A Practical Primer. Available from RD Instruments, 9855 Businesspark Av., San Diego, CA 92131Routine processing, quality control, and calibration are performed at the host institute. Standard checks include detecting and correcting time errors, applying transducer-level temperatures and salinities to obtain a better estimate of the sound speed for the velocity calculation, editing out bad bins or profiles that have been contaminated by interference with the bottom or some other physical object such as a hydro wire, and verifying the quality of the gyrocompass and the navigation data. The final gyrocompass estimates of ship heading and the navigation information are the primary sources for calibrating the ADCP's relative current velocities. Typically, one is correcting for a "angle" error due to misalignment of the transducer relative to the ship's hull and an "amplitude" component related mostly to minor imperfections of the transducer geometry. Relative current velocity errors caused by these components are orthogonal; the angle errors lead to uncertainties of the athwartships velocity component while the amplitude error introduces uncertainties along the ship track.The navigation calculation is performed once calibration is complete. Absolute currents over a fixed depth range (reference layer) are obtained by subtracting the average of the ship velocity relative to a reference layer (i.e. ADCP velocities) from the absolute ship velocity over the ground (from navigation, i.e., GPS). The raw absolute current velocities relative to the reference layer are smoothed to reduce the effects of noise in the position fixes and combined with the navigation data to obtain the best estimates of ship positions and velocities, which are stored into the data base. Thus, absolute currents at any depth can be determined from the final ship navigation data and the relative ADCP measurements.What is the data quality?For the shipboard ADCP, the processing and quality assessment have been left to the data originator. For the majority of cruises, the data were processed and documented using the CODAS software distributed by the E.Firing Laboratory at the University of Hawaii. Profiles were screened objectively and subjectively, but personnel and methods changed over time. For data contributed by other institutions using non-CODAS software, the data originators were instructed to contribute only processed and documented data sets. Once these data arrive at the JASADCP, a general review of the data is undertaken, but no specific flagging system is added.The heterogeneity of operational conditions--ship speed, sea state, and distribution of acoustic scatterers--makes it difficult to quantify the data quality for a given cruise. Conditions and data quality can vary greatly during a single cruise. Data quality also varies with depth in each profile, with problems being most common in the top bin and towards the end of the profiling range. The data user is therefore referred to the documentation file accompanying each cruise for notes about adverse conditions and corresponding data quality problems at specific times during a cruise. Additional quality information is available in the high-resolution data set stored in Common Oceanographic Data Access System (CODAS) blockfiles. For each depth of each profile, a flag byte shows the results of editing, partly by hand and partly mechanized. A "percent good" byte records the percentage of single ping samples accepted by the ADCP for averaging at each depth bin in each ensemble-average profile (typically 5 minutes, the shortest interval for which data are saved). Both the flag byte and "percent good" (> 30%) are used when extracting data for the ASCII standard subset. For more insight and control, users may wish to extract data from the CODAS directly, using their own criteria. Caldwell, P., 1995. NODC archives shipboard ADCP data. Earth System Monitor, Vol. 5, No. 3, pp. 4-8. Caldwell, P., 1996. Advances from the shipboard ADCP Archive Center. Earth System Monitor, Vol. 6, No. 3, p. 14. Firing, E., 1992. Notes from acoustic Doppler Current Profiler Workshop at the National Oceanographic Data Center, May 14-15, 1992. "unpublished manuscript." Hawaii NODC Liaison Office, Dept. of Oceanography, 1000 Pope Rd.,Univ. of Hawaii, Honolulu, HI 96822 Process_Date: Unknown Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Mr. Patrick C. Caldwell Contact_Organization: NOAA/NESDIS/NODC/NCDDC Contact_Position: Hawaii/US Pacific Liaison, Joint Archive for Shipboard ADCP manager Contact_Address: Address_Type: mailing Address: 1000 Pope Road, MSB 316 Address: Dept. of Oceanography Address: University of Hawaii at Manoa City: Honolulu State_or_Province: Hawaii Postal_Code: 96822 Country: USA Contact_Voice_Telephone: (808)-956-4105 Contact_Facsimile_Telephone: (808) 956-2352 Contact_Electronic_Mail_Address: caldwell@hawaii.edu Contact_Electronic_Mail_Address: patrick.caldwell@noaa.gov Hours_of_Service: 8 AM to 5 PM weekdays Contact_Instructions: check services@nodc.noaa.gov if not available Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Joint Archive for Shipboard ADCP: Database November 26, 2007 *Only cruises received after the last submission to NODC (April 10, 2006 to November 26, 2007) are included, for a total of 78 cruises, from 12 ships. Data organized in directories as: /SAC_ID (unique cruise) Information regarding each SAC_ID can be seen in file: cruise_list_for_Apr_2007_NODC_xfer.txt Total size on this tape: 1.1 gigabytes Files on this directory: ship.ref: ship names, subdirectory abbreviations, ship codes cruise_list_for_Nov2007_NODC_xfer.txt: Identification Numbers (SAC IDs), year of cruise, ship name, cruise name given by PI format_and_method.txt: format description for NODC standard subset and notes on data reduction For each cruise (unique directory): sssss.sub "standard subset (hourly and 10 m depth intervals for U,V, transducer temp, and ship U, ship V, for sac_id=sssss, ie. 00123.sub" sssss.bft "cruise summary, or block footer as we call it" sssssnnn.blk "CODAS block nnn for cruise sssss" sssssdir.blk "CODAS block directory for cruise sssss" THE NODC STANDARD SUBSET OF SHIPBOARD ADCP DATA The NODC provides shipboard ADCP data in two formats: 1) a high-resolution set in CODAS binary format consisting of currents and ancillary parameters at the sampling interval with which the data were recorded and processed and 2) an ASCII standard subset of absolute currents at hourly and 10 m intervals. If absolute currents are not available due to lack of navigation, then relative currents are provided. If NODC receives data sets that are not of high resolution, then the standard subset may be of a slightly different timing sequence than hourly and the depth spacing may be other than 10 m. For instance, if a data set is received as gridded averages in space, then a nominal time will be assigned. Similarly, if a data set is received with 8 m depth spacing, then this interval is used in the subset. The standard subset includes the hourly means and standard deviations of ship velocity components and the transducer temperature, when available. A description of the methodology and format of the standard subset is given below. METHODOLOGY The standard subset will consist of absolute currents if the ship navigation was satisfactory. Otherwise the currents will be given relative to the mean over a reference layer, usually 50 to 150 m. In the vertical, each velocity profile is linearly interpolated to a regular grid at integral multiples of 10 m. The shallowest level is the first multiple of 10 m that is greater than or equal to the depth of the first good bin of the recorded data, typically a function of the instrument configuration and the transducer depth. The deepest level is that at which at least 50% of the ensembles over the course of the cruise have a Percent Good greater than 30%. For each depth bin, the Percent Good is the percentage of individual pings in an ensemble with valid data. As noted above, for data sets received at NODC in a reduced form (ie., not high-resolution), the original depth interval is maintained. In time, averages are calculated for one-hour intervals centered on the hour. The time column in the ASCII subset gives the mean of the times of the ensembles that fall into the interval. Hence the mean may be slightly off the integral hour, even when ensembles are evenly available over the entire hour. The mean time may be even less centered in the case where data are only partially available over the interval because instrument recording was turned off (e.g., at port calls). In the case where data are totally unavailable over the entire interval so no mean time can be calculated, a "placeholder" entry is made and assigned a time value exactly at the middle of the interval, i.e., on the hour, followed by bad value flags for the longitude, latitude and velocity fields. It is left to the user to manipulate the time column if a truly even time grid is desired. At each level, a bad value flag is given if less than 50% of the ensembles in the hour have valid data. Bad value flags (99999) for velocity components also occur at depth layers where less than 50% of the ensembles in the interval contribute to the average because of low percent good and other editing criteria, or in the case of absolute currents, occur over the entire depth range because ship velocity was not available as a reference. The transducer temperature is provided as a mean and standard deviation over the hour. The ship velocity is provided as means and standard deviations of the components over the hour and is derived from the final absolute ship velocities of each ensemble as stored in the CODAS high-density database. The ship velocity information allows one to see at a glance if the ship was on-station, underway, or both over the hour. FORMAT DESCRIPTION ====> HEADER RECORD sac_id=xxxxx yr_base=yyyy start_lev=ddm num_lev=ddd type < > denotes optional e.g. sac_id=00001 yr_base=1993 start_lev= 20m num_lev= 45 absolute depth_int= 8m where sac_id is a unique identifier for the cruise (NODC bookkeeping) yr_base is the year inwhich the cruise begins start_lev is starting level (meters) num_lev is the number of levels type means either "absolute" or "relative" currents depth_int is the depth interval or spacing between levels and is left blank if equal to 10 m (default) If a data set is received at NODC in a reduced form (ie., not high- resolution), then a comment will be appended to the header to define the timing scheme and the depth spacing if it is other than hourly or 10 m. A complete documentation file which describes the cruise, instrumentation, processing, and other pertinent comments for the given cruise will be available separately. ====> DATA RECORD The format is designed for ease of application; therefore, the date-time and positions are provided in decimal form as a single field. Each data record will be fixed length although the length may vary from cruise to cruise due to differences in the number of depth bins. The order of each record is as follows: With a template such as: ddd.fffff dddd.dddd ddd.dddd tt.t tt.tt suu.u su.uu svv.v sv.vv uuuuu vvvvv .. e.g. 350.00002 157.9365 6.9120 28.9 0.01 -4.6 0.11 -3.4 0.09 419 177 .. field template comment ddd.fffff: decimal day; e.g. 0.50000 is 1200 UTC on January 1 of the year given by yr_base; always present dddd.dddd ddd.dddd: longitude and latitude decimal degrees; lon positive east, lat positive north; missing flag= 1E38; e.g. -145.1667 is 145 deg 10' W tt.t tt.tt transducer temperature mean and standard deviation (deg C); missing = 1E38 suu.u su.uu svv.v sv.vv absolute ship velocity components means and standard deviations in m/sec; missing = 1E38 uuuuu vvvvv current components in mm/sec; bad or missing = 99999; e.g. 121 is 12.1 cm/s Total volume (bytes): 1,006,531,261 Total cruises: 78 Total ships: 12 For complete ship information, see ship_list.txt JASADCP SACID YEAR SHIP_CODE CRUISE 00990 2003 nhorizon.usa nh0306 00991 2002 knorr.usa kn166_11 00993 2002 ronbrown.usa rb0207 00994 2002 ronbrown.usa rb0208b 00995 2002 ronbrown.usa rb0209 00997 1999 ronbrown.usa rb9906 00998 2000 ronbrown.usa rb0001 00999 2000 ronbrown.usa rb0002 01000 2000 ronbrown.usa rb0004 01001 2000 ronbrown.usa rb0006 01002 2000 ronbrown.usa rb0008 01003 2001 ronbrown.usa rb0102 01004 2001 ronbrown.usa rb0104 01005 2001 ronbrown.usa rb0106 01006 2001 ronbrown.usa rb0108 01007 2001 ronbrown.usa rb0109 01008 2005 ronbrown.usa rb0505_lta 01009 2005 ronbrown.usa rb0506_lta 01010 2006 hiialaka.usa hi0610 01011 2005 kaimoana.usa ka0505-gp505 01012 2005 kaimoana.usa ka0506a-gp705a 01013 2005 kaimoana.usa ka0506b-gp705b 01014 2005 kaimoana.usa ka0507-gp805 01015 2006 kaimoana.usa ka0601-gp106 01016 2006 kaimoana.usa ka0602-gp206 01017 2006 kaimoana.usa ka_transit_May06 01018 2001 kaiyoxk.jpn KY0111_transit 01019 2001 kaiyoxk.jpn KY0111_L1 01020 2001 kaiyoxk.jpn KY0111_L2 01021 2002 kaiyoxk.jpn KY0210 01022 2003 kaiyoxk.jpn KY0312 01023 2004 lmgould.usa LG0401 01024 2004 lmgould.usa LG0402 01025 2004 lmgould.usa LG0403 01026 2004 lmgould.usa LG0404 01027 2004 lmgould.usa LG0405 01028 2004 lmgould.usa LG0406 01029 2004 lmgould.usa LG0407 01030 2004 lmgould.usa LG0411 01031 2004 lmgould.usa LG0412 01032 2003 ronbrown.usa RB0309 01033 2003 melville.usa mv0302 01034 2005 oscsette.usa OS0511 01035 2005 nbpalmer.usa np0502nb150 01036 2005 nbpalmer.usa np0502bb38 01037 2005 nbpalmer.usa np0502nb38 01038 2005 nbpalmer.usa np0505nb150 01039 2005 nbpalmer.usa np0506nb150 01040 2005 nbpalmer.usa np0506bb38 01041 2005 nbpalmer.usa np0506nb38 01042 2005 nbpalmer.usa np0507nb150 01043 2005 nbpalmer.usa np0507bb38 01044 2005 nbpalmer.usa np0507nb38 01045 2005 nbpalmer.usa np0508nb150 01046 2005 nbpalmer.usa np0508bb38 01047 2005 nbpalmer.usa np0508nb38 01048 2006 nbpalmer.usa np0601nb150 01049 2006 nbpalmer.usa np0601bb38 01050 2006 nbpalmer.usa np0601nb38 01051 2006 nbpalmer.usa np0602anb150 01052 2006 nbpalmer.usa np0602abb38 01053 2006 nbpalmer.usa np0602anb38 01054 2006 nbpalmer.usa np0602nb150 01055 2006 nbpalmer.usa np0602bb38 01056 2006 nbpalmer.usa np0602nb38 01057 2006 nbpalmer.usa np0603nb150 01058 2006 nbpalmer.usa np0603bb38 01059 2006 nbpalmer.usa np0606nb150 01060 2006 nbpalmer.usa np0606nb150 01061 2007 rrevelle.usa knox03rr_I8S 01062 2007 rrevelle.usa knox03rr_I8S 01063 2006 thompson.usa TN191_leg1_bb 01064 2006 thompson.usa TN191_leg1_nb 01065 2006 thompson.usa TN191_leg2_bb 01066 2006 thompson.usa TN191_leg2_nb 01067 2005 oscsette.usa OS0512 01068 2006 oscsette.usa OS0602 01069 2006 oscsette.usa OS0603 JASADCP Vessel Country NODC Years applicable SHIP_CODE Name CODE hiialaka.usa Hi_Ialakai United_States_of_America 33HL all_years kaimoana.usa Ka`imi`moana United_States_of_America 33KM all_years kaiyoxk.jpn Kaiyo Japan 49XK all_years knorr.usa Knorr United_States_of_America 316N all_years lmgould.usa Laurence_M_Gould United_States_of_America 33LG all_years melville.usa Melville United_States_of_America 318M all_years nbpalmer.usa Nathaniel_B._Palmer United_States_of_America 3206 all_years nhorizon.usa New_Horizon United_States_of_America 31NM all_years oscsette.usa Oscar_Elton_Sette United_States_of_America 33OC all_years rrevelle.usa Roger_Revelle United_States_of_America 33RR all_years ronbrown.usa Ron_Brown United_States_of_America 33RO all_years thompson.usa Thomas_G._Thompson United_States_of_America 31TT 1963-1991 3250 1992- Entity_and_Attribute_Detail_Citation: none Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: NOAA/NESDIS/National Oceanographic Data Center Contact_Person: Data Access Group, User Services Team Contact_Address: Address_Type: mailing and physical Address: SSMC-3 Fourth Floor Address: 1315 East West Highway City: Silver Spring State_or_Province: MD Postal_Code: 20910-3282 Country: USA Contact_Voice_Telephone: 301-713-3277 Contact_Facsimile_Telephone: 301-713-3302 Contact_Electronic_Mail_Address: services@nodc.noaa.gov Hours_of_Service: 8am-5pm, Monday through Friday Resource_Description: NODC Accession Number 0036863 Distribution_Liability: NOAA makes no warranty regarding these data,expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA, NESDIS, NODC and NCDDC cannot assume liability for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function on a particular system. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: CODAS and ASCII Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://www.nodc.noaa.gov/cgi-bin/search/prod/accessionsView.pl/details/0036863 Fees: Prices vary depending on data set, output medium and ordering mechanism. A standard handling charge, with additional costs for special handling, may be added to the basic cost of the data. Ordering_Instructions: Prepayment by check, money order or bank card is required. Orders may be placed via fax, email, regular mail, telephone or via the NNDC Online Store. Metadata_Reference_Information: Metadata_Date: 20071126 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Mr. Patrick C. Caldwell Contact_Organization: NOAA/NESDIS/NODC/NCDDC Contact_Position: Hawaii/US Pacific Liaison Contact_Address: Address_Type: mailing Address: 1000 Pope Road, MSB 316 Address: Dept. of Oceanography Address: University of Hawaii at Manoa City: Honolulu State_or_Province: Hawaii Postal_Code: 96822 Country: USA Contact_Voice_Telephone: (808)-956-4105 Contact_Facsimile_Telephone: (808) 956-2352 Contact_Electronic_Mail_Address: caldwell@hawaii.edu Contact_Electronic_Mail_Address: patrick.caldwell@noaa.gov Hours_of_Service: 8 AM to 5 PM weekdays Contact_Instructions: check services@nodc.noaa.gov if not available Metadata_Standard_Name: FGDC CSDGM Metadata_Standard_Version: FGDC-STD-001-1998