Chofu Maru, Ryofu Maru, Shumpu Maru, and Kofu Maru
Bridge Observation
Quality Control Report


Kennard B. Kasper and Shawn R. Smith






World Ocean Circulation Experiment (WOCE)





Surface Meteorological Data Assembly Center

Center for Ocean Atmospheric Prediction Studies

Florida State University


August 20, 2001


Report WOCEMET 98-01




Version 5.0


 



 

Addendum:

Members of the WOCE Hydrographic Project Office (WHPO) and WOCEMET met at the 13th Data Products Committee (DPC) meeting in College Station, TX to discuss reconciliation of the WOCE cruise line designators. This was done in anticipation of the future release of version 3 of the WOCE global data set, and resulted in changes to several WOCE cruise line designations.

On December 21, 2000, WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK) cruises P__09_/01 and P__09S/02 to be referenced as P__09_/00. The quality control information for these data sets has been left in the report for the user, but please note that the lines previously known as P__09_/01 and P__09S/02 are now combined together under P__09_/00.

On May 11,2001 WOCEMET combined the WOCE designation for the Chofu Maru's (Identifier: JCCX) cruises PR_19_/06 and PR_19_/07 to be referenced as PR_19_/06. The quality control information for this data set has been left in this report for the user, but please note that the lines previously known as PR_19_/06 and PR_19_/07 are now combined together under PR_19_/06.

On August 6, 2001 WOCEMET combined the designators for the Kofu Maru's (Identifier: JDWX) cruises PR_03N/03 and PR_03N/04 to be referenced as PR_03N/03. The quality control information for this data set has been left in this report for the user, but please note that the lines previously known as PR_03N/03 and PR_03N/04 are now combined under PR_03N/03.

On August 20, 2001 WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK) cruises PR_02_/01 and PR_02_/02 to be referenced as PR_02_/01.

WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK)cruises PR_02_/03 and PR_02_/04 to be referenced as PR_02_/03.

WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK) cruises PR_02_/06 and PR_02_/07 to be referenced as PR_02_/06.

WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK) cruises PR_02_/10 and PR_02_/11 to be referenced as PR_02_/10.

WOCEMET combined the WOCE designation for the Ryofu Maru's (Identifier: JGZK) cruises PR_02_/13 and PR_02_/14 to be referenced as PR_02_/13.

WOCEMET combined the WOCE designation for the Shumpu Maru's (Identifier: JFDG) cruises PR_17_/11 and PR_17_/12 to be referenced as PR_17_/11.


 



 

Introduction:

The data referenced in this report are bridge observations collected by the research vessels Chofu Maru (identifier: JCCX), Ryofu Maru (JGZK), Shumpu Maru (JFDG), and Kofu Maru (JDWX). The data provider was Michio Aoyama of the Japanese Meteorological Agency, and the data were received in electronic format. A conversion to the standard FSU format was completed. 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 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 every 3 hours by the research vessel's bridge crew. Values for the following parameters were collected, although some variables were not measured by each research vessel and on each cruise:

Time

(TIME)
Latitude(LAT)
Longitude(LON)
Earth Relative Wind Direction(DIR)
Earth Relative Wind Speed(SPD)
Sea Temperature(TS)
Atmospheric Pressure(P)
Air Temperature(T)
Wet-Bulb Temperature(TW)
Dewpoint Temperature(TD)
Present Weather(WX)
Total Cloud Amount(TCA)
Low or Middle Cloud Amount(LMCA)
Cloud Base Height(ZCL)
Low Cloud Type(LCT)
Middle Cloud Type(MCT)
High Cloud Type(HCT)


Table 1 highlights parameters that were not collected for each of the 62 cruises described in this report. For each cruise, table 2 lists the start and end date, number of values, number of records, number of flags, and percentage of values flagged. A total of 64,934 values were evaluated for the 62 cruises and 30 flags were added by the preprocessor and Data quality Evaluator. The flagged values are 0.05 percent of the total values.

Table 1: Values Not Collected
RV/CTCTIMELATLONDIRSPDTSPTTWTDWXTCALMCAZCLLCTMCTHCT
JCCX
PR_18_/01
PR_18_/02
PR_18_/03
PR_18_/04
PR_18_/06
PR_18_/07
PR_18_/08
PR_18_/09
PR_18_/10
PR_18_/11
PR_18_/12
PR_19_/06
PR_19_/07
PR_18_/13
PR_18_/14
PR_18_/15
PR_18_/16

       
















X
 





X
  
X

X
X


X
X



X
X
X


X
   
JGZK
PR_04_/01
PR_02_/01
PR_02_/02
PR_02_/03
PR_02_/04
PR_03_/02
PR_02_/05
PR_04_/02
PR_02_/06
PR_02_/07
PR_03_/04
PR_02_/09
PR_01_/02
PR_04_/03
PR_02_/10
PR_02_/11
PR_03_/09
PR_02_/12
PR_04_/04
PR_02_/13
PR_02_/14
PR_02_/15
P__09_/01
P__09S/02

            
X
X



X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

X

X
   
JFDG
PR_17_/01
PR_17_/02
PR_17_/03
PR_17_/05
PR_17_/06
PR_17_/07
PR_17_/08
PR_17_/09
PR_17_/10
PR_17_/11
PR_17_/12
PR_17_/13
PR_17_/14
PR_17_/15
PR_17_/16
PR_17_/18
PR_17_/20

       















X
X
 





X

X
  









X
X

X



X
   
JDWX
PR_03N/01
PR_03N/02
PR_03N/03
PR_03N/04
             

X

X
   




Table 2: Statistical Cruise Information

RV/CTCDatesNumber of
Records
Number of
Values
Number of
Flags
Percentage
Flagged
JCCX     
PR_18_/011/24/91-1/30/915181600
PR_18_/024/27/91-5/6/9175127500
PR_18_/038/3/91-8/9/914775200
PR_18_/0410/16/91-10/25/9177123200
PR_18_/064/25/92-5/4/9274125800
PR_18_/077/24/92-7/29/924368800
PR_18_/0810/5/92-10/7/921930400
PR_18_/091/19/93-1/26/935791200
PR_18_/104/26/93-5/5/9373124100
PR_18_/117/21/93-7/29/934779900
PR_18_/1210/18/93-10/22/933457800
PR_19_/0610/29/93-10/31/931930400
PR_19_/0711/6/93-11/9/932946400
PR_18_/131/18/94-1/22/943149600
PR_18_/144/26/94-4/30/943762900
PR_18_/157/20/94-7/27/945390100
PR_18_/161/17/95-1/21/953248000
R/V Total 7981312900
JGZK     
PR_04_/016/15/90-6/29/90114182400
PR_02_/017/3/90-7/13/9078124800
PR_02_/027/21/90-7/30/9075127500
PR_02_/0311/3/90-11/11/9069117310.09
PR_02_/0411/17/90-11/27/9080136000
PR_03_/0212/4/90-12/16/9095152000
PR_02_/051/19/91-2/5/91135216010.05
PR_04_/026/7/91-6/21/91113180820.11
PR_02_/066/25/91-7/6/9188140820.14
PR_02_/077/14/91-7/23/9176121600
PR_03_/0411/16/91-11/28/9199158400
PR_02_/091/19/92-2/4/92127203270.34
PR_01_/022/10/92-3/9/92125200000
PR_04_/036/10/92-6/24/92113180840.22
PR_02_/106/29/92-7/9/9280128010.08
PR_02_/117/17/92-7/26/9278124800
PR_03_/0910/23/92-10/30/925486400
PR_02_/121/20/93-2/4/93118188800
PR_04_/046/10/93-6/24/93117187220.11
PR_02_/136/29/93-7/10/9386137620.15
PR_02_/147/18/93-7/28/9381137700
PR_02_/151/19/94-2/6/94142227200
P__09_/017/8/94-7/28/94164278840.14
P__09S/028/2/94-8/24/94174278440.14
R/V Total 248140165300.07
JFDG     
PR_17_/012/24/91-2/27/912034000
PR_17_/025/2/91-5/5/912135700
PR_17_/037/18/91-7/20/912034000
PR_17_/052/4/92-2/14/923254400
PR_17_/064/25/92-4/29/923254400
PR_17_/077/9/92-7/13/923251200
PR_17_/089/22/92-10/2/9267113900
PR_17_/092/12/93-2/15/932946400
PR_17_/105/26/93-6/4/932847600
PR_17_/117/13/93-7/18/933860800
PR_17_/127/25/93-7/26/931117600
PR_17_/1310/11/93-10/13/93915300
PR_17_/142/13/94-2/19/943149600
PR_17_/154/28/94-5/2/943457800
PR_17_/167/15/94-7/19/942847600
PR_17_/184/24/95-4/29/952743200
PR_17_/208/21/95-8/25/953451000
R/V Total 493814500
JDWX     
PR_03N/0110/20/90-10/31/9088149600
PR_03N/0210/12/91-10/20/9166105600
PR_03N/0311/3/92-11/6/923152700
PR_03N/0411/12/92-11/15/922641600
R/V Total 211349500




Table 3: Number of Flags and Percentage Flagged for Each Variable On the R/V Ryofu Maru (JGZK)

Variable
FGQSTotal Number of FlagsPercentage of Variable Flagged
TIME00
LAT880.32
LON8   80.32
DIR1120.08
SPD31150.20
TS 220.08
P1 120.08
T 110.04
TW 110.04
TD 110.04
WX  00
TCA00
ZCL00
LCT00
MCT00
HCT00
LMCA00
Total Number of Flags1642830 
Percentage of All Values
Flagged

0.04

0.01

0.00*

0.02

0.07

* value less than 0.01 percent
Summary:
The bridge observations are in excellent condition with only 0.05 percent of the total data being flagged for errors. In addition, table 2 reveals that flags were only applied to the JGZK bridge observations. Table 3 summarizes these flags, accounting for 0.07% of the JGZK data. A discussion of the flags follows.


Unrealistic Platform Speed ("F" flags):
A few latitude and longitude variables were flagged with the "F" flag. These flags indicate that the platform speed computed by the preprocessor exceeds a realistic speed for a research vessel (15 meters per second). These latitude and longitude positions should be used with caution.

Value Greater Than 4 Standard Deviations from Climatology ("G" flags):
The preprocessor assigned "G" flags to earth relative wind speed and pressure data. The flags identify values that are greater than 4 standard deviations from the Da Silva (1994) climatology for each parameter. This test does not necessarily indicate erroneous values, just extreme data.

Data Arrived at the DAC Flagged Questionable ("Q" flags):
"Q" flags represent values that arrived at the DAC already flagged as suspect. No reason for these suspect values was provided to the DAC; however, the flags were retained and converted to our format. The data should be used with caution.

Spike in the Data ("S" flags):
The Data Quality Evaluator applied "S" flags to various parameters. The flags indicate values that are drastically out of the current data trend.


Final Comments:
These data are in excellent condition and should prove reliable for the user. Keep in mind that many of the cruises are missing values for ZCL.

References:

da Silva, A.M., C.C. Young and S. Levitus, 1994: Atlas of Surface Marine Data 1994, Volume 1: Algorithms and Procedures. NOAA Atlas Series.

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.