Metadata:
  Identification_Information:
    Citation:
      Citation_Information:
        Originator: Dr. Roger Lukas
        Publication_Date: Unknown
        Title: CTD Data of the Hawaii Ocean Time-series (HOT) program in the
North Pacific 100 Miles North of Oahu, Hawaii for Cruises
HOT189-198 during 2007
    Description:
      Abstract: The HOT program makes repeated observations of the physics, biology and
chemistry at a site approximately 100 km north of Oahu, Hawaii. Two stations
are visited about once a month: Kahe Point (Station 1:  21.34N, 158.27W) and
Station ALOHA (Station 2: 22.75N, 158W).  Various other stations are made
intermittently in support of similar research objectives or mooring
deployments.
                                                                                       
HOT CTD data are collected using a SeaBird CTD 9-11 Plus
with dual sensors at the maximum sampling rate of 24 samples per second
(24 Hz). They are screened for errors and processed to 2-dbar averages.
Starting in 2006, the percent transmission field was replaced with
a nitrate in the dataset.
                                                                                       
In separate NODC Accessions, Niskin bottle and thermosalinograph data
from these same cruises are available.
      Purpose: The objective of the physical component of HOT is to describe and understand the ocean climate and variability at a deep-water site in the North Pacific subtropical gyre near Hawaii. This requires a long time series of physical oceanographic variables, including water mass properties and currents,supporting and complementing the objectives of the biogeochemical component of HOT.
      Supplemental_Information: NOAASupplemental:Entry_ID: Unknown
Sensor_Name: Sea-Bird CTD SBE-9/llPlus system
Source_Name: ship
Project_Campaign: Hawaii Ocean Time series (HOT)
Originating_Center: University of Hawaii
Storage_Medium: ASCII
Reference: None
Online_size: 8101 Kbytes
    Time_Period_of_Content:
      Time_Period_Information:
        Range_of_Dates/Times:
          Beginning_Date: 200701
          Ending_Date: 200712
      Currentness_Reference: ground condition
    Status:
      Progress: Complete
      Maintenance_and_Update_Frequency: quasi-monthly cruises
    Spatial_Domain:
      Bounding_Coordinates:
        West_Bounding_Coordinate: -158.27
        East_Bounding_Coordinate: -158.00
        North_Bounding_Coordinate: 22.75
        South_Bounding_Coordinate: 21.34
    Keywords:
      Theme:
        Theme_Keyword_Thesaurus: None
        Theme_Keyword: hyrdorgraphic data
        Theme_Keyword: profile data
        Theme_Keyword: CTD
        Theme_Keyword: Pressure (Decibars)
        Theme_Keyword: Temperature (Degrees Celsius,
        Theme_Keyword:    International Temperature Scale of 1990)
        Theme_Keyword: Salinity (1978 International Practical Salinity Scale)
        Theme_Keyword: Oxygen (micromoles per kilogram)
        Theme_Keyword: Chloraphyll, Pigment (uG/L)
        Theme_Keyword: Nitrate (uMOL/KG)
      Place:
        Place_Keyword_Thesaurus: None
        Place_Keyword: Hawaii Ocean Time Series (HOT)
        Place_Keyword: Station Aloha
        Place_Keyword: Kahe Point
        Place_Keyword: Kaena Point
        Place_Keyword: Oahu
        Place_Keyword: Hawaii
        Place_Keyword: HALE ALOHA
        Place_Keyword: Pacific
        Place_Keyword: central north Pacific
      Stratum:
        Stratum_Keyword_Thesaurus: None
        Stratum_Keyword: complete ocean profile surface to bottom
    Access_Constraints: None
    Use_Constraints: Dataset credit required
    Point_of_Contact:
      Contact_Information:
        Contact_Person_Primary:
          Contact_Person: Dr. Roger Lukas
          Contact_Organization: Department of OceanographySchool of Ocean and Earth Science and TechnologyUniversity of Hawaii
        Contact_Position: Principal Investigator-- Physical data (non-ADCP)
        Contact_Address:
          Address_Type: Mailing and physical address
          Address: 1000 Pope Rd
          Address: Marine Science Bldg. Room 418
          City: Honolulu
          State_or_Province: HI
          Postal_Code: 96822
          Country: USA
        Contact_Voice_Telephone: 808-956-7892
        Contact_Electronic_Mail_Address: rlukas@soest.hawaii.edu
    Data_Set_Credit: Hawaii Ocean Time-series (HOT) was initiated and funded through grants from the National Science 
Foundation under the auspices of the Joint Global Ocean Flux Study 
(JGOFS) and the World Ocean Circulation Experiment (WOCE). The
field phase of these programs has ended, but support from the Ocean 
Sciences Division of NSF has enabled continuation of our basic HOT 
measurement program. The physical oceanographic component contributes to 
the objectives of the World Climate Research Programme (WCRP) 
Climate Variability and Predictability (CLIVAR) Programme by providing 
information on interannual to decadal variability of the North Pacific Ocean.
The US CLIVAR Office funded the physical oceanographic data during
2007.
    Native_Data_Set_Environment: ASCII text files, FORTRAN/C ready
  Data_Quality_Information:
    Logical_Consistency_Report: see methodology
    Completeness_Report: quality control completed
    Lineage:
      Process_Step:
        Process_Description: Generalities are given below.  Please see REFERENCES for additional
information. 

Each of the (approximately monthly) HOT cruises follows the same basic
pattern with some flexibility for ancillary projects to be done after the
core sampling has been completed. During transit from Honolulu to the
time-series station ALOHA (A Long-term Oligotrophic Habitat Assessment) one
weight test is done to between 700 and 1000 m at station 1 off Kahe Point
(16 km offshore from the western tip of Oahu, 21 20.6' N, 158 16.4' W,
1500 m water depth). Following the successful winch test, a CTD/rosette cast
to 1000 m is conducted. This cast serves as a "shakedown" for the remainder
of the cruise, and the functioning of the components of the CTD/rosette
system as well as coordination between winch, deck and console operators can
be tested. The training of new personnel in activities such as taking
meteorological observations, and sampling salinities is also done in this
station. The data taken at Kahe Point (station 1) represent an additional
time-series of water properties at a near-shore site.
                                                                                        
Upon arrival at ALOHA (station 2), operations commence with a deep cast
(maximum depth approximately 4750 m), 36-hour burst sampling3 of the upper
1000 m at the same location, plus CTD casts to support ancillary JGOFS work
of about an extra 12 hours duration. Time permitting, the last CTD cast of
the cruise will be a deep cast. On occasion, one cast will be done at
station 3 (40 miles north of ALOHA at 23 25' N, 158 W).
                                                                                        
The second and following casts at station ALOHA are sampled to at least 1000
m depth. Cast 2 is called a "density cast" because water samples are taken
at a number of specified density values ranging from [sigma-theta]= 27.37 to
the surface with the intent to resolve the profiles of salinity, dissolved
oxygen, and nutrients in potential density coordinates Depths sampled during
the following casts within the 36-hour burst sampling period are chosen both
by the science teams, who have to ensure that at least one
water sample each is taken within the mixed layer, the shallow salinity
maximum, the intermediate salinity minimum and the deepest position of
the rosette for calibration of the CTD conductivity sensor. If oxygen
bottles will be taken from the cast, then the sampling should include
at least the mixed layer, oxygen maximum, oxygen minimum and the deepest
rosette position for calibration of the CTD oxygen sensor. The second
deep cast of the cruise (if there is one) should include sampling of
oxygen bottles in at least seven levels appropriate for calibration of
the CTD oxygen sensor, i.e. in the oxycline and two more levels below
the oxygen minimum, in addition to the four levels mentioned before.
                                                                                        
The primary objective of the HOT program is to assess variability in the
central Pacific Ocean on annual and interannual time scales. One of our most
important concerns, therefore, is to ensure that the highest possible
precision and accuracy is consistently maintained for all water column
chemical measurements. In order to achieve the highest possible data
quality, we have instituted a quality-assurance/quality-control program,
and have attempted to collect all ancillary information necessary to
ensure that our data are not biased by sampling artifacts.
                                                                                        
Because sampling is over 36 hours, one can average out the effects
short-term changes of the depth of density surfaces and the magnitude of
hydrographic and nutrient variables (inertial, tidal, and shorter periods).
                                                                                        
CTD data were acquired at a rate of 24 samples per second. Digital
data were stored on a laptop personal computer and, for redundancy, the
analog signal was recorded on VHS videotapes. Backups of CTD data were
made onto Zip disks and later onto compact disks. The raw CTD data were
quality controlled and screened for spikes as described in Winn et al.
(1993).  Data alignment, averaging, correction and reporting were done
as described in Tupas et al.  (1993). Salinity spike rejection parameters
were modified for some cruises in 2004 because of rough sea conditions.
Spikes occur when the CTD samples the disturbed water of its wake;
therefore, samples from the downcast are rejected when the CTD is moving
upward or when its acceleration exceeds 0.5 m s-2 in magnitude. Cruises 155,
156, and 157 were conducted under 19 relatively rough conditions. The CTD
acceleration cutoff value had to be increased to between 0.55 and 0.65 m s-2
for some of the casts to relax the data rejection criteria and avoid
eliminating an excessive number of points.  The data were additionally
screened by comparing the temperature and conductivity sensor pairs. These
differences permitted identification of problems in the sensors. Only the
data from one set of T-C sensors and one oxygen sensor, whichever was
deemed most reliable, is reported here.

INSTRUMENTS
Continuous measurements of temperature, salinity, oxygen and
fluorescence are made with a Sea-Bird SBE-9/11Plus CTD package
with dual temperature, salinity and oxygen sensors and fluorometer
described in Fujieki (2004). CTD underwater unit No.91361
was used during 2006.
                                                                                        
Starting HOT-177 (2006), the Transmissometer (XMISS) data that was
once included in the CTD files have been replaced by continuous Nitrate
measured using Satlantic's InSitu Underwater Spectrometer (ISUS V2).
Satlantic's ISUS V2 is a chemical free sensor that uses UV absorption
technology to provide accurate nitrate concentration measurements in
real-time.
                                                                                        
Temperature is reported in the ITS-90 scale. Salinity and all derived
units were calculated using the UNESCO (1981) routines; salinity is
reported in the practical salinity scale (PSS-78).  Oxygen is reported in
&#181;mol kg-1 and Chloropigment (Fluorescence) in &#181;g/l.

1996 Tupas, L., F. Santiago-Mandujano, C.  Nosse, D. Hebel, E. Firing, R. 
   Lukas, and D. Karl. Hawaii Ocean Time-series Program Data Report 7, 1995. 
   SOEST Tech. Report 96-7, School of Ocean and Earth Science and Technology, 
   Univ. of Hawaii, Honolulu, HI, 228 pp.

2006 Fujieki, L.A., F. Santiago-Mandujano, P. Lethaby, 
   R.  Lukas, and D. Karl. Hawaii Ocean Time-series Program Data
   Report 18, 2006.  School of Ocean and Earth Science and Technology,
   Univ. of Hawaii, Honolulu, HI, 475 pp.
        Process_Date: Unknown
        Process_Contact:
          Contact_Information:
            Contact_Person_Primary:
              Contact_Person: Dr. Roger Lukas
              Contact_Organization: Department of OceanographySchool of Ocean and Earth Science and TechnologyUniversity of Hawaii
            Contact_Position: Principal Investigator-- Physical data (non-ADCP)
            Contact_Address:
              Address_Type: Mailing and physical address
              Address: 1000 Pope Rd
              Address: Marine Science Bldg. Room 418
              City: Honolulu
              State_or_Province: HI
              Postal_Code: 96822
              Country: USA
            Contact_Voice_Telephone: 808-956-7892
            Contact_Electronic_Mail_Address: rlukas@soest.hawaii.edu
  Entity_and_Attribute_Information:
    Overview_Description:
      Entity_and_Attribute_Overview: Directories and files:
/data             root data directory
/0-data           Files as received by NODC from the originator
  /woce_sum       WOCE-type sum file which gives details on
                  position and parameters taken of each cast and
                  station of each cruise.  Filenaming convention:
                                                                                        
                  hotccc.sum      where ccc is cruise number
                                                                                        
  /ctd            CTD data.  Filenaming convention:
                                                                                        
                  hcccasstt.ctd   where ccc is cruise number
                                        a   is constant
                                        ss  is station number
                                        tt  is cast number
                                                                                        
CTD Data Format Document, January 13, 1992
                                                                                        
    CTD data are distributed in a format specified by the international
WOCE Hydrographic Programme Office (WHPO).  This document describes
that format.
                                                                                        
    Each station/cast is stored in a separate file.  A file's name can be
determined by the concatenation of 'h', 2 digit cruise number, 'a', a 2 digit
station number, a 2 digit cast number and a file extension of ctd.  For ex-
ample, HOT-1, station 2, cast 3, would be found in h01a0203.ctd.
                                                                                        
    The cruise and position information for each cast is in the cruise
summary file (*.sum).  The EXPOCODE, station number and cast number
can be used to cross-reference the CTD data files with the cruise
summary file.  This code allows for the identification of the cruise.
It consists of a 4 character NODC country-ship code, a maximum of 8
character cruise number followed by a "/" and leg number.  For example,
the EXPOCODE for HOT-13 on the R/V Moana Wave would be 31MW013/1.
                                                                                        
    The CTD data file has a fixed record length of 65 characters / record.
The first six records of a CTD file contain header information:
                                                                                        
    Record 1:
       Column  Format   Item
         9-22     a14   EXPOCODE (KA=Kaimalino,WE=Wecoma,MW=Moana Wave)
        31-34     a4    WHP station identification
        41-42     i2    Month
        43-44     i2    Day
        45-46     i2    Year
        FORTRAN FORMAT  (8x,a14,8x,a4,6x,3i2)
        C               "%*s %s %*s %s %*s %2d%2d%2d"

    Record 2:
         7-12     a6    Station number
        20-22     i3    Cast number
        36-40     i5    Number of data records in the file
        FORTRAN FORMAT  (6x,a6,7x,i3,13x,i5)
        C               "%*s %d %*s %d %*s %d"
                                                                                        
    Record 3:
        16-21     i6    Instrument number
        37-41    f5.2   Sampling rate (hz)
        FORTRAN FORMAT  (15x,i6,15x,f5.2)
        C               "%*s %d %*s %f"
                                                                                        
    Record 4:
        Headers for data columns (variable labels).
                                                                                        
    Record 5:
        Unit header for data columns.
                                                                                        
    Record 6:
        Quality byte designators.  All columns requiring a quality
        byte are underscored by seven asterisks.
                                                                                        
                                                                                        
     The remaining records contain CTD data. The order of variables in a
record are as follows: pressure, temperature, salinity, oxygen, nitrate,
fluorescence and quality.  Missing values are flagged with -99.0.
                                                                                        
   Data Record Format:
                                                                                        
        Column  Format  Item
         1-8    f8.1    Pressure (Decibars)
         9-16   f8.4    Temperature (Degrees Celsius,
                           International Temperature Scale of 1990)
        17-25   f9.4    Salinity (1978 International Practical Salinity Scale)
        26-33   f8.1    Oxygen (micromoles per kilogram)
        34-41   f8.3    Nitrate (micro Moles per Kilogram)
        42-49   f8.3    CHLPIG (uG/L)
        50-57    i8     Number of observations averaged at this pressure level
        58-65    i8     Quality (defined by investigator) **
        FORTRAN FORMAT  (f8.1, f8.4, f9.4, f8.1, 2f8.3, i8, i8)
        C               "%f %f %f %f %f %f %d %d"
                                                                                        
**  The quality word is the left-to-right concatenation of required qualityi
 bytes for the variables measured.  They are defined as follows:
                                                                                        
 byte value  Definition
     1       Not calibrated with water samples.
     2       Acceptable measurement.
     3       Questionable measurement.
     4       Bad measurement.
     5       Not reported.
     6       Interpolated value.
     7       Not assigned for CTD data
     8       Not assigned for CTD data
     9       Not sampled
      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 xxxxxxx
    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: ASCII
        Digital_Transfer_Option:
          Online_Option:
            Computer_Contact_Information:
              Network_Address:
                Network_Resource_Name: http://data.nodc.noaa.gov/accession/xxxxxxx
      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: 20081105
    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@soest.hawaii.edu
        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
