Vickers Quality Control Report Parks Camp Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean Atmosphere Response Experiment (COARE) Surface Meteorological Data Processing Center Center for Ocean Atmospheric Prediction Studies The Florida State University April 26, 1996 Report COAREMET 95-17 Version 1.1 Notes Concerrning Version 1.1: Further investigation of the wind data revealed an error in our flagging code. The result was the erroneous overflagging of the wind data. All "E" flags were removed from the wind data and replaced with "Z" (good data flag). The following report includes the changes to the flag statistics fro the Vickers. Introduction: The data referenced in this report were collected from the research vessel, Vickers (call sign WTEC), SAIL meteorological system (data acquired from Colorado State University Department of Atmospheric Sciences) for TOGA COARE during the Intensive Observing Period (IOP). The files provided to the DPC contained interpolated five minute average data (known as CIDS data) compiled from the ten second SAIL measurements. All data were converted to a standard format and were then preprocessed using an automated data quality checking program. The data were then visually inspected by a data quality analyst who reviewed, modified, and added appropriate quality control (QC) flags to the data. This report summarizes the flags for the Vickers data sets, including both flags added by the preprocessor and the analyst. Statistical Information: The data from the Vickers during the IOP were expected to include observations every five minutes from 0000 UTC on November 1, 1992 to 2400 UTC on February 28, 1993 (120 days) resulting in at most 34,560 data values for each variable. Time (TIME), latitude (LAT), longitude (LON), platform heading (PL_HD), platform speed (PL_SPD), earth relative wind direction (DIR), earth relative wind speed (SPD), atmospheric pressure (P), temperature (T), sea surface temperature (TS), and relative humidity (RH) were quality controlled. The availability of data for each day and the percentage of the data flagged is given in Table 1. There were 28,330 records for the Vickers and up to eleven variables for each record resulting in 311,630 values that were reviewed and checked. Table 2 details the distribution of flags and includes the percentages flagged for each variable sorted by flag type. Table 1: Availability of Data for the Vickers (WTEC) File* #Records #Values %Flagged WTEC.921104001v102.nc 205 2255 6.56 WTEC.921105001v102.nc 288 3168 0.06 WTEC.921106001v102.nc 272 2992 0.03 WTEC.921107001v102.nc 25 1375 0.51 WTEC.921109001v102.nc 246 2706 0.04 WTEC.921110001v102.nc 176 1936 0.05 WTEC.921111001v102.nc 227 2497 4.57 WTEC.921112001v102.nc 261 2871 9.47 WTEC.921113001v102.nc 272 2992 10.03 WTEC.921114001v102.nc 285 3135 2.55 WTEC.921115001v102.nc 288 3168 0.00 WTEC.921116001v102.nc 288 3168 0.00 WTEC.921117001v102.nc 288 3168 0.25 WTEC.921118001v102.nc 122 1342 0.37 WTEC.921119001v102.nc 288 3168 0.06 WTEC.921120001v102.nc 288 3168 0.09 WTEC.921121001v102.nc 288 3168 0.28 WTEC.921122001v102.nc 288 3168 0.47 WTEC.921123001v102.nc 288 3168 0.76 WTEC.921124001v102.nc 284 3124 0.13 WTEC.921125001v102.nc 283 3113 0.00 WTEC.921126001v102.nc 288 3168 0.00 WTEC.921127001v102.nc 288 3168 0.03 WTEC.921128001v102.nc 288 3168 0.16 WTEC.921129001v102.nc 288 3168 0.00 WTEC.921130001v102.nc 288 3168 0.28 WTEC.921201001v102.nc 288 3168 0.32 WTEC.921202001v102.nc 267 2937 0.17 WTEC.921203001v102.nc 275 3025 0.00 WTEC.921204001v102.nc 288 3168 0.00 WTEC.921205001v102.nc 288 3168 0.32 WTEC.921206001v102.nc 288 3168 0.09 WTEC.921207001v102.nc 288 3168 0.16 WTEC.921208001v102.nc 288 3168 0.09 WTEC.921209001v102.nc 288 3168 0.13 WTEC.921210001v102.nc 281 3091 0.03 WTEC.921211001v102.nc 256 2816 0.07 WTEC.921218001v102.nc 288 3168 0.00 WTEC.921219001v102.nc 277 3047 0.03 WTEC.921220001v102.nc 288 3168 0.03 WTEC.921221001v102.nc 288 3168 0.03 WTEC.921222001v102.nc 288 3168 0.47 WTEC.921223001v102.nc 288 3168 0.19 WTEC.921224001v102.nc 288 3168 0.44 WTEC.921225001v102.nc 288 3168 0.44 WTEC.921226001v102.nc 288 3168 4.80 WTEC.921227001v102.nc 264 2904 1.69 WTEC.921228001v102.nc 288 3168 0.22 WTEC.921229001v102.nc 288 3168 4.67 WTEC.921230001v102.nc 288 3168 0.09 WTEC.921231001v102.nc 288 3168 0.57 WTEC.930101001v102.nc 288 3168 0.22 WTEC.930102001v102.nc 279 3069 0.20 WTEC.930103001v102.nc 288 3168 0.06 WTEC.930104001v102.nc 288 3168 0.54 WTEC.930105001v102.nc 288 3168 0.13 WTEC.930106001v102.nc 288 3168 0.82 WTEC.930107001v102.nc 288 3168 1.33 WTEC.930108001v102.nc 288 3168 0.28 WTEC.930109001v102.nc 288 3168 0.00 WTEC.930110001v102.nc 288 3168 0.09 WTEC.930111001v102.nc 288 3168 0.09 WTEC.930112001v102.nc 288 3168 0.06 WTEC.930113001v102.nc 288 3168 0.19 WTEC.930114001v102.nc 288 3168 0.19 WTEC.930115001v102.nc 288 3168 0.35 WTEC.930116001v102.nc 288 3168 0.13 WTEC.930117001v102.nc 288 3168 0.13 WTEC.930118001v102.nc 288 3168 0.25 WTEC.930119001v102.nc 288 3168 1.01 WTEC.930120001v102.nc 288 3168 9.53 WTEC.930127001v102.nc 57 627 0.00 WTEC.930128001v102.nc 288 3168 0.09 WTEC.930129001v102.nc 288 3168 0.32 WTEC.930130001v102.nc 288 3168 0.19 WTEC.930131001v102.nc 288 3168 0.28 WTEC.930201001v102.nc 288 3168 0.13 WTEC.930202001v102.nc 288 3168 0.13 WTEC.930203001v102.nc 288 3168 0.19 WTEC.930204001v102.nc 288 3168 0.13 WTEC.930205001v102.nc 288 3168 0.28 WTEC.930206001v102.nc 288 3168 0.16 WTEC.930207001v102.nc 288 3168 0.44 WTEC.930208001v102.nc 288 3168 4.07 WTEC.930209001v102.nc 288 3168 0.09 WTEC.930210001v102.nc 288 3168 0.44 WTEC.930211001v102.nc 288 3168 0.19 WTEC.930212001v102.nc 288 3168 0.35 WTEC.930213001v102.nc 288 3168 0.51 WTEC.930214001v102.nc 288 3168 0.41 WTEC.930215001v102.nc 288 3168 0.16 WTEC.930216001v102.nc 288 3168 0.28 WTEC.930217001v102.nc 288 3168 0.28 WTEC.930218001v102.nc 288 3168 0.47 WTEC.930219001v102.nc 288 3168 0.38 WTEC.930220001v102.nc 288 3168 0.13 WTEC.930221001v102.nc 288 3168 1.33 WTEC.930222001v102.nc 288 3168 1.10 WTEC.930223001v102.nc 288 3168 0.41 WTEC.930224001v102.nc 288 3168 0.98 WTEC.930225001v102.nc 288 3168 0.41 WTEC.930226001v102.nc 288 3168 0.13 Total 28330 311630 0.78 *The dates are found in the first 6 digits after the call letters (yymmdd). Table 2: Frequency of Flags Assigned for Each Variable and Flag Type for the Vickers (WTEC) Variable Unrealistic > 4 S.D. From Bad Platform Spike Total Percent of Platform Climatological Data Moves in Number Variable Movement Mean Over Land Data of Flags Records Flagged TIME 0 0 LAT 82 1 83 0.29 LON 82 1 83 0.29 PL_HD 86 86 0.30 PL_SPD 13 27 40 0.14 DIR 38 38 0.13 SPD 43 165 208 0.73 P 249 249 0.88 T 6 622 8 636 2.24 TS 148 66 214 0.76 RH 750 48 798 2.82 Total 164 197 1,385 2 687 2,435 Per cent 0.05 0.06 0.44 0.00* 0.22 0.78 of Total Data Flagged * Less then .005% of this data type were flagged Summary: As the statistical information indicates, all of the data are considered to be in good condition. Two minor problems did occur. The first minor problem occurred in temperature data. Many values were flagged as erroneous data. These erroneous values were either extremely high temperature values greater than forty degrees Celsius, or they were values that were around zero. In some cases these extremes coincided with extremes in the relative humidity data. The other minor problem occurred in the relative humidity data. Many values were flagged as erroneous data. These values were extremely low relative humidity values. There were no relative humidity values for the first seven days and the sensor reported relative humidities on the order of 40% for the next four days with a large jump to relative humidities on the order of 80% on the eleventh day of the cruise. Other values around zero were flagged as erroneous data. These values often coincided with temperature values of zero. Final Notes: There should not be any problems in using data. Reference: 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. In preparation.