Data Access
Level 1B Limb data contains calibrated radiance data over multiple scans that are geolocated into a GUVI-based coordinate system on the limb.
Version:2.2.2
Level 1B Limb data contains calibrated radiance data over multiple scans that are geolocated into a GUVI-based coordinate system on the limb.
| Role | Person | StartDate | StopDate | Note | |
|---|---|---|---|---|---|
| 1. | PrincipalInvestigator | spase://SMWG/Person/Andrew.B.Christensen |
This web page allows the request of data files for this product. To request data: select the year and day then press display.
Starting date/time of file's observation encoded in a 13-digit string and stored as a single netCDF global attribute.
Dimensions: [1] - this parameter is a single element per file.
Stopping date/time of file's observation encoded in a 13-digit string and stored as a single netCDF global attribute.
Dimensions: [1] - this parameter is a single element per file.
Date of observation in number of days since start of current year.
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Time of observation in integral number of milliseconds since start of current day. Timestamp marks beginning of interval
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Detector number of detector being used
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Slit position being used where 0 = closed, 1 = wide, 2 = medium, 3 = narrow, and 4 = unknown.
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Starting position of the mirror.
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Position of the mirror when at nadir.
Dimensions: [n] - where n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Four separate dark pixels that measure instumental dark counts. These values are use to scale a dark pixel mask to obtain an estimated dark level that can then subtracted from each pixel.
Dimensions: [4,n] - where 4 is the number of dark count pixels, or NumDarkCountPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
GUVI long backgrounds measured on a 3x7 grid (3 spatial pixel intervals, 7 scan/mirror step intervals), and integrated for time intervals of [1.088, 1.674,1.674, 1.674, 1.674, 1.674, 1.488] seconds, finishing at scan/mirror steps [ 31, 26, 53, 80, 107, 134, 158]. The first 32 steps are on the limb (1.088 = 32x0.034 seconds/ limb step), whereas the next six intervals are distributed across the 32 disk scan steps.
Dimensions: [21,n] - where 21 is the number of background count pixels, or NumBackgroundCountPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Data quality indicator stored as bit-encoded integers where Bit 7: 1 = Negative Radiance, 0 = positive; Bit 6: 1 = Zero Radiance, 0 = non-zero; Bit 5: 1 = Geolocation error (disk pixel on limb or limb pixel on disk), 0 = correct geolocation; Bit 4: 1 = Calibration failure, 0 = No calibration failure; Bits 0-3 are unused.
Dimensions: [5,14,32,n] - where 5 is the number of colors, or NumColors; 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Background Star At Pixel Indicator stored as integers: 1 = true; 0 = false.
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Tangent Point Latitude
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Tangent Point Longitude
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Tangent Point Altitude
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Zenith Angle
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Right Ascension
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Declination
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Calibration error
Dimensions: [5,14,32,n] - where 5 is the number of colors, or NumColors; 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Count error
Dimensions: [5,14,32,n] - where 5 is the number of colors, or NumColors; 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Solar Zenith Angle
Dimensions: [14,32,n] - where 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.
Radiance scans of nominally 14 pixels along track and 32 pixels crosstrack for each of 5 colors (1216, 1304, 1356 A, LBH1 and LBH2).
Dimensions: [5,14,32,n] - where 5 is the number of colors, or NumColors; 14 is the number of along track pixels, or NumAlongTrackPixels; 32 is the number of across track pixels, or NumAcrossTrackPixels; n is the number of scans, or NumScans, (i.e., records) in an orbital file.