Franklin research 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 29 November, 1995 Report COAREMET 95-21 Version 1.0 Introduction: The data referenced in this report were collected from the research vessel Franklin (call sign VJJF; data acquired from Dr. Frank Bradley at the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia) for TOGA COARE during the Intensive Observing Period (IOP). The files provided to the DPC contained fifteen minute data and underwent intensive processing prior to arrival at FSU (see appendix). The observations were taken separately from the Franklin's own on-board instruments using high resolution instruments brought onboard the ship before the cruises. The 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 Franklin data sets, including both flags added by the preprocessor and the analyst. Statistical Information: The data from the Franklin during the IOP were expected to include observations every fifteen minutes from two cruises. Table 1 provides a listing of the cruises and their start and end dates. Time (TIME), latitude (LAT), longitude (LON), platform heading (PL_HD), platform speed (PL_SPD), earth relative wind direction (DIR), earth relative wind speed (SPD), temperature (T), specific humidity (Q), sea temperature (TS), sea surface temperature (TS2), and precipitation (PRECIP) were quality controlled. The available number of records on each cruise leg and the percentage of the data flagged is given in Table 2. There were 4,212 total records for the Franklin and up to twelve variables for each record resulting in 50,544 values that were reviewed and checked. The number of flags added was 1,425, resulting in 2.8193% of the total data being flagged. Table 3 provides a list of the flags assigned to each variable and the percentages of each flag. Table 1: Cruise Information Cruise Leg Start Date End Date Total Number of Days 1 11/22/92 12/14/92 14 2 01/10/93 02/04/93 25 Table 2: Availability of Data Cruise Leg Number of Records Total Number of Data Values Percent Flagged 1 1,851 22,212 6.0733 2 2,361 28,332 0.2682 Total 4,212 50,544 2.8193 Table 3: Frequency of Flags Assigned for Each Variable and Flag Type for the Franklin Research Data Original Data Data are Greater Platform Platform Spikes Total Percent of Out of Unrealistic than 4 s.d. from Moves Position in Number Variable Variable Realistic Range Movement the Da Silva Mean Over Land Uncertain Data of Flags Records Flagged TIME 0 0 LAT 4 1 605 610 14.4824 LON 4 1 605 610 14.4824 PL_HD 0 0 PL_SPD 178 178 4.2260 DIR 0 0 SPD 1 1 0.0237 T 0 0 Q 0 0 TS 2 2 0.0475 TS2 3 21 24 0.5698 PRECIP 0 0 TOTAL 181 8 22 2 1,210 2 1,425 Percent of Total Data Flagged 0.3581 0.0158 0.0435 0.0040 2.3940 0.0040 2.8193 Position data problems: The major problem with the Franklin research data concerns the position data during the first cruise. Dr. Bradley reported a problem with the GMS receiver early in leg 1 so all of these positions were flagged as uncertain. Other problems with the position data occurred at four points where platform movement was flagged as being unrealistic and at one point which was flagged by the preprocessor as being over land. These positions should be used with caution. Summary: As the statistical information indicates, most of the Franklin Research data is considered to be in good condition. Other than the position uncertainty mentioned above, the only other major problem occurred in the platform speed data. One hundred seventy-eight platform speed data values were flagged as being out of realistic range. Each of these values indicated a negative platform speed. The negative speeds were generally between 0 m/s and -1 m/s. These values do not appear to associated with the position data uncertainty so no explanation for this these speed values is known. Therefore, the data analysts recommends that this data be used with caution. A few minor problems were found in the sea temperature data where twenty-one points were flagged as being greater than four standard deviations from the da Silva climatological mean (1994), and three points were flagged as being out of the realistic range. Other than these values, the data analysts does not foresee problems in the using the remainder of the 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. Appendix: The data received at the DPC arrived after intensive processing was done to the original data set by CSIRO. The following is information concerning the cruises of the Franklin and the associated data which was gathered and processed. Surface meteorological data were obtained during the two Franklin COARE cruises out of Townsville Fr 9/92, 18 November 1992 - December 17, 1992 and Fr 1/93, January 7, 1993 - February 9, 1993. Each cruise was interrupted by a port call in Rabaul, November 30 - December 1, 1992 and January 21-22, 1993. The meteorological sensors were high-resolution instruments installed specially for COARE on the foremast at 11.3 meters above sea level. An infrared radiometer for SST was installed above the wheel house pointed at 45 degree to the sea surface. Bulk sea temperature was measured by the ship's thermosalinograph taking water from 2.4 meters below the surface. Original data notes: 1. Date, Time are UTC and mark the beginning of the 15-minute averaging period. 2. LAT, LON are also position at the beginning of the 15-minutes. NOTE: at the beginning of cruise 9/92 the GMS receiver was crooked, and produced serious (up to 30 km) jumps. These position data are not reliable. 3. Air temperature and specific humidity are from a Bradley-design aspirated psychrometer. 4. TS is ship's thermosalinograph data from the CSIRO Division of Oceanography archive. 5. True wind speed is corrected for flow distortion over the ship (-3%) and increased by a fixed 0.2 m/s following intercomparisons with Moana Wave. 6. SST is from the IR radiometer, adjusted for emissivity and sky reflection with a fixed correction of 0.4C. 7. Rainfall is from an optical rain gauge (ORG) mounted on the foremast.