Hawaiian Ocean Time Series Experiment
Bridge Observations
Quality Control Report





David F. Zierden and Shawn R. Smith





World Ocean Circulation Experiment (WOCE)





Surface Meteorological Data Assembly Center

Center for Ocean Atmospheric Prediction Studies

Florida State University


August 22, 2001


Report WOCEMET 97-12




Version 2.0

Addendum:

On August 22, 2001 the Hawaiian Ocean Time Series Experiment (HOTS) data providers notified the Data Assembly Center (DAC) of some problems in the meteorological data for HOTS cruises 1-59. This resulted in several changes to the HOTS data.

The longitude on the Moana Wave's (Identifier: WUS9293) cruise PRS02_/02 on 12/04/88 at 20:00 (WOCEMET time stamp 4695600 in .nc file) was changed from 200.59 to 201.93.

The latitude on the Moana Wave's (Identifier: WUS9293) cruise PRS02_/13 on 01/07/90 at 08:00 (WOCEMET time stamp 5269440 in .nc file) was changed from 11.85 to 22.85. Consequently, the S flag that corresponded to this value was removed.

The longitude on the Moana Wave's (Identifier: WUS9293) cruise PRS02_/41 on 10/20/92 at 16:00 (WOCEMET time stamp 6734400 in .nc file) was changed from 201 to 202. Consequently, the S flag that corresponded to this value was removed.

The latitude on the Moana Wave's (Identifier: WUS9293) cruise PRS02_/52 on 02/19/94 at 08:00 (WOCEMET time stamp 7435200 in .nc file) was changed from 22.01 to 22.76. Consequently, the S flag that corresponded to this value was removed.

The last two time stamps on the Moana Wave's (Identifier: WUS9293) cruise PRS02_/59 on 11/21/94 (WOCEMET time stamps 7831440 and 7831440 in .nc file) were identical. The first time stamp was changed from 11/21/94 at 12:00 to 11/21/94 at 08:00 (WOCEMET time stamp changed from 7831440 to 7831200 in .nc file). The second time 11/21/94 at 12:00 was left unchanged. Consequently, the T and F flags that corresponded to these values were removed.

Two records on the Wecoma's (Identifier: WSD7079) cruise PRS02_/32 had the same date and time. The first record listed as 12/07/91 at 08:00 (WOCEMET time stamp 6276000 in .nc file) was left unchanged. The second record listed as 12/07/91 at 08:00 (WOCEMET time stamp 6276000 in .nc file) was changed to 12/8/91 at 08:00 (WOCEMET time stamp 6277440 in .nc file). Consequently, the T and F flags that corresponded to these values were removed.

The cruise identifier for the Townsend Cromwell (TCROMWE) has been changed to (WTDF).


Introduction:

The data referenced in this report are bridge observations collected during the Hawaiian Ocean Time Series Experiment by the research vessels Alpha Helix (identifier: ALHELIX), Kaimalino (KAIMALI), Thompson (KTDQ), Townsend Cromwell (TCROMWE), New Horizon (WKWB), Wecoma (WSD7079), and Moana Wave (WUS9293). The data provider was Fernando Santiago Mondujano and the data were received in electronic format. A conversion to the standard FSU format was completed after modifications were made according to Appendix A. The data were then preprocessed using an automated data screening program. Next, the Data Quality Evaluator reviewed, modified and added appropriate quality control (QC) flags to the data. Details of the WOCE QC procedures can be found in Smith et al (1996). The data quality control report summarizes the flags for the Hawaiian Ocean Time Series Experiment bridge observations, including those added by both the preprocessor and the Data Quality Evaluator.


Statistical Information:

The data referenced in this report were expected to include observations taken approximately every 4 hours by the research vessel's bridge crew. Values for the following variables were collected, although some variables were not measured on different research vessels and cruises:

Time (TIME)
Latitude (LAT)
Longitude (LON)
Platform Course (PL_CRS)
Platform Speed (PL_SPD)
Earth Relative Wind Direction (Meteorological) (DIR)
Earth Relative Wind Speed (SPD)
Sea Temperature (TS)
Atmospheric Pressure (P)
Air Temperature (T)
Wet Bulb Temperature (TW)
Present Weather (WX)
Total Cloud Amount (TCA)

The variables for which values were collected on each cruise are summarized in table 1. The platform relative wind speed and direction were also measured and can be made available to the

Table 1: Values Collected
RV/ CTCTIMELATLONPL CRSPL SPDDIRSPDTSPTTWWXTCA
ALHELIX             
PRS02_/28XXXXXXXXXXXXX
PRS02_/29XXXXXXXXXXXXX
KAIMALI             
PRS02_/04XXXXX  XXXX  
PRS02_/06XXXXX  XXXX  
PRS02_/07XXXXX  XXXX  
PRS02_/08XXXXX  XXXX  
PRS02_/09XXXXX  XXXX  
PRS02_/10XXXXX  XXXX  
PRS02_/14XXXXX  XXXX  
PRS02_/15XXXXX  XXXX  
PRS02_/17XXXXX  XXXX  
PRS02_/19XXXXX  XXXX  
KTDQ             
PRS02_/45XXXXXXXXXXXXX
TCROMWE             
PRS02_/44XXXXXXXXXXXXX
WKWB             
PRS02_/47XXXXXXXXXXXXX
WSD7079             
PRS02_/16XXXXX  XXXX  
PRS02_/18XXXXX  XXXX  
PRS02_/31XXXXXXXXXXXXX
PRS02_/32XXXXXXXXXXXXX
PRS02_/33 XXXXXXXXXXXXX
PRS02_/34XXXXXXXXXXXXX
PRS02_/35XXXXX  XXXX  
PRS02_/36XXXXX  XXXX  
PRS02_/46XXXXXXXXXXXXX
WUS9293             
PRS02_/01XXXXX  XXXX  
PRS02_/02XXXXX  XXXX  
PRS02_/03XXXXX  XXXX  
PRS02_/05XXXXX  XXXX  
PRS02_/11XXXXX  XXXX  
PRS02_/12XXXXX  XXXX  
PRS02_/13XXXXX  XXXX  
PRS02_/20XXXXX  XXXX  
PRS02_/22XXXXX  XXXX  
PRS02_/30XXXXXXXXXXXXX
PRS02_/37XXXXXXXXXXXXX
PRS02_/38XXXXXXXXXXXXX
PRS02_/39XXXXXXXXXXXXX
PRS02_/40XXXXXXXXXXXXX
PRS02_/41XXXXXXXXXXXXX
PRS02_/49XXXXXXXXXXXXX
PRS02_/50XXXXXXXXXXXXX
PRS02_/51XXXXXXXXXXXXX
PRS02_/52XXXXXXXXXXXXX
PRS02_/53 XXXXXXXXXXXXX
PRS02_/54XXXXXXXXXXXXX
PRS02_/55XXXXXXXXXXXXX
PRS02_/56XXXXXXXXXXXXX
PRS02_/57XXXXXXXXXXXXX
PRS02_/58XXXXXXXXXXXXX
PRS02_/59XXXXXXXXXXXXX


Table 2: Statistical Cruise Information

RV/ CTCDatesNumber of RecordsNumber of ValuesNumber of
Flags
Percentage
flagged
ALHELIX     
PRS02_/287/08/91 - 7/12/912022041.81
PRS02_/298/08/91 - 8/12/911819800.00
KAIMALI     
PRS02_/042/28/89 - 2/29/8965400.00
PRS02_/065/17/89 - 5/19/891513500.00
PRS02_/076/24/98 - 6/26/891513500.00
PRS02_/087/28/89 - 7/31/89181621811.1
PRS02_/098/23/89 - 8/26/891816200.00
PRS02_/109/21/89 - 9/24/891816200.00
PRS02_/142/15/90 - 2/17/901311700.00
PRS02_/153/18/90 - 3/21/9098100.00
PRS02_/175/09/90 - 5/11/90109000.00
PRS02_/19 7/24/90 - 7/27/901513500.00
KTDQ     
PRS02_/452/16/93 - 2/18/931314300.00
TCROMWE     
PRS02_/441/20/93 - 1/22/931516500.00
WKWB     
PRS02_/475/19/93 - 5/22/931516500.00
WSD7079     
PRS02_/164/12/90 - 4/14/901412600.00
PRS02_/186/12/90 - 6/15/9098100.00
PRS02_/3110/20/91 - 10/24/912224262.48
PRS02_/3212/05/91 - 12/09/912123141.73
PRS02_/331/04/92 - 1/08/922224231.24
PRS02_/342/13/92 - 2/17/922931900.00
PRS02_/353/04/92 - 3/08/92272432811.5
PRS02_/364/16/92 - 4/20/922421600.00
WUS9293     
PRS02_/0110/31/88 - 10/31/8821800.00
PRS02_/0212/01/88 - 12/03/881816200.00
PRS02_/031/07/89 - 1/10/891816200.00
PRS02_/053/26/89 - 3/29/891816200.00
PRS02_/1110/17/89 - 10/20/891513500.00
PRS02_/1211/27/89 - 11/29/8998100.00
PRS02_/131/04/90 - 1/07/901412610.79
PRS02_/209/14/90 - 9/15/9021800.00
PRS02_/2212/17/90 - 12/20/901715300.00
PRS02_/309/17/91 - 9/20/911718700.00
PRS02_/376/08/92 - 6/10/921617600.00
PRS02_/387/04/92 - 7/06/921516500.00
PRS02_/398/04/92 - 8/07/921516500.00
PRS02_/409/21/92 - 9/23/921415400.00
PRS02_/4110/18/92 - 10/21/921314310.70
PRS02_/499/13/93 - 9/16/931819800.00
PRS02_/5010/28/93 10/30/931819800.00
PRS02_/511/19/94 - 1/22/941819821.01
PRS02_/522/16/94 - 2/19/941819810.50
PRS02_/533/08/94 - 3/11/941617600.00
PRS02_/546/18/94 - 6/21/941112100.00
PRS02_/557/24/94 - 7/27/942022000.00
PRS02_/568/29/94 - 9/01/941718700.00
PRS02_/579/22/94 - 9/25/941819800.00
PRS02_/5810/14/94 - 10/17/941920900.00
PRS02_/5911/18/94 - 11/21/941213253.79


user upon request. The cruises for which DIR and SPD values are missing did not provide all of the variables necessary to correctly calculate true winds. Values for wind relative to the vessel, course, speed, and heading must all be present in order to calucuate SPD and DIR. Present weather (WX) and total cloud amount (TCA) data were collected on many of the cruises and may also be made available upon request. Other details of each cruise including start and end date, number of values, number of records, number of flags and percentage flagged are listed in table 2. A total of 8075 values were evaluated with 73 flags added by preprocessor and Data Quality Evaluator for a total of 0.91 percent of the values being flagged. The distribution of these flags for each variable is detailed in table 3.


Table 3: Number of Flags and Percentage Flagged for Each Variable

VariableBFKSTTotal Number of FlagsPercentage of Variable Flagged
TIME    881.03
LAT 4 4 80.90
LON 5271 334.26
PL_CRS     00.00
PL_SPD     00.00
DIR  1  10.13
SPD     00.00
TS   1 10.13
P 19  1 202.58
T     00.00
TW   2 20.26
WX     00.00
TCA     00.00
Total Number of Flags 

19


9


28


9


8


73


0.91
Percentage of flags Used 

0.24


0.10


0.35


0.10


0.08


0.91
 


Summary:

The bridge observations from the Hawaiian Ocean Time Series Experiment proved to be very reliable. No major or systematic errors were found in the data. Only a few minor problems were flagged.

Minor Problems
:

18 "J" flags were applied to P on cruise PRS02_/08 for values over 1100 mb.

8 "T" flags were applied to TIME by the prescreener for time duplication.

Isolated "F" and "S" flags were applied to LAT and LON by the prescreener and the evaluator.

All LON values on cruises PRS02_/35 and PRS02_/36 were given "K" flags for fluctuations up to 2 degrees.

Isolated "S" flags were applied to P, TS, and TW.

Cruises PRS02_/01 and PRS02_/20 contained only two records each, so no evaluation by the Data Quality Evaluator was possible.


Final Note:

These data are in excellent condition and should prove reliable for the user. Keep in mind that some of the cruises are missing values for DIR, SPD, WX, and TCA.


References:

Smith, S. R., C. Harvey, and D. M. Legler, 1996: Handbook of Quality Control Procedures and Methods for
Surface Meteorology Data.
WOCE Report No. 141/96, Report WOCEMET 96-1, Center for Ocean
Atmospheric Prediction Studies, Florida State University, Tallahassee, FL 32301.


Appendix A: Modifications to HOTS Data

Some modifications were made to the Hawaiian Ocean Time Series Experiment data before they were prescreened and quality controlled by the Data Quality Evaluator. These changes are classified as major and minor modifications.

Major Modifications:


All LON values were converted to degrees east to fit the DAC convention.

PL_SPD and SPD were converted from knots to meters per second on all cruises (multiplied by 0.5144)

All values less than zero were changed to -9999, the missing value flag, on PL_CRS, PL_SPD, TS, P, T, TW.

The following cruises had out of sequence TIME values and were sorted into chronological order: PRS02_/02, PRS02_/12, PRS02_/18, PRS02_/31, PRS02_/32, PRS02_/33.

SPD and DIR were checked for correct coding of calm winds. If the direction variable was zero and the corresponding speed value was greater than zero, then the direction value was changed to 360 degrees. Conversely, if the speed variable was zero and the corresponding direction value was greater than zero, then the direction value was changed to zero degrees.

The following records were removed due to missing LAT/LON values:

CruiseTIME (year, mon., day, hr.)
PRS02_/12Nearly half of records
PRS02_/0689 5 18 12
89 5 19 12
89 5 19 20
PRS02_/0989 8 25 20
PRS02_/2290 12 18 4

Some or all of the P values on the following cruises were reported in inches of mercury and converted to millibars (multiplied by 33.86215): PRS02_/31, PRS02_/32, PRS02_/49, PRS02_/51, PRS02_/52, PRS02_/53, PRS02_/54, PRS02_/55


Minor Modifications:


The hour in the TIME values 88 12 3 24 and 88 12 2 24 (YY MM DD HH) were changed from 24 to 0 to maintain a correct time sequence on cruise PRS02_/02.

The dates in the last two values of the TIME variable were changed from 89 2 29 to 89 3 1 (YY MM DD) on cruise PRS02_/04 since 1989 was not a leap year.

The month in the TIME value was changed from 91 1 19 0 to 91 9 19 0 (YY MM DD HH) to maintain a correct time sequence on cruise PRS02_/30.