E10 QUIKSCAT LITE

QuikSCAT Lite is a simplified wind product that provides a primary wind vector solution for the marine community. Each file contains one solution of the wind vector as a function of time and location from the QuikSCAT data (described in Section E9). One or two QuikSCAT Lite files are created for each spacecraft orbit. The file naming provides the date and time span over which the data is valid.

E10.1 QuikSCAT Lite Naming Convention

The QuikSCAT Lite data products obey the SPP guidelines for file naming. The file names use all of the fields that are standard for orbital data. An example of a file name is:

wndvc_qs1_d20010709_s142400_e153800_b1070203_cness.wvl

where:

wndvc	is the unique data product identifier.

qs1	is the QuikSCAT spacecraft identifier.

wvl	is the wind vector list file format specifier.

E10.2 QuikSCAT Lite File Format

The QuikSCAT Lite File is a packed binary 16-bit integers, which are stored most significant byte first. Each file contains a series of records. Each record contains a date and time followed by 76 observations. Each record corresponds to one cross-track scan of the Sea Winds Instrument. There are no header or trailer records in the file structure. The file structure is shown in Figure E35.

Figure E35. QuikSCAT Lite File Structure

Each record contains a Date-Time Field followed by nine data vectors. The Date-Time Field contains four values. Each data vector contains 76 values. All values in the record are 2-byte integers that are stored with the most significant byte first in the file.

The Date-Time Field contains the day number and time of the observations that are in the subsequent data vectors. The year is not included in the record information and must be inferred from the file name. Although the seconds of time are stored in the file, the values in this field should not be considered. Only the values in the other fields are correct for the observations.. These parameters are described in Table 72.

Table E72. QuikSCAT Date-Time Field Parameters

Word #	Variable	Scaling	Description
1	Day of Year	None	Value from 1 to 366
2	Hours of Day	None	Value from 0 to 23
3	Minutes	None	Value from 0 to 59
4	Seconds	None	Value from 0 to 59

The nine data vectors that follow the Date-Time Field contain the following information. Each vector contains 76 values that are related to the preceding Date-Time Field. Table 73 describes these parameters.

Table E73. Data Vector Parameters

Word #	Variable	Scaling	Description
5 - 80	Latitude	100*degrees
81 - 156	Longitude	100*degrees
157 - 232	Quality
233 - 308	Wind_speed	100*m/second
309 - 384	Direction	100*degrees	Angle with respect to North (0 degrees with positive angles increasing in the clockwise direction).
385 - 460	Rain_flag
461 - 536	Spare	Not used
537 - 612	Spare	Not used
613 - 688	Spare	Not used