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Supporting Data

GRAS SAF NRT and Offline sounding data products also include the following supporting parameters:
  • LEO and occulting GPS satellite identifiers
  • Horizontal location (latitude, longitude)
  • Vertical location (ellipsoidal height, height above msl, geopotential height, pressure level)
  • Date and time
  • Quality information
  • Precise Orbit Determination (POD) information
  • Impact parameter (smoothed & sampled)
  • Bending angle (smoothed & sampled)
  • Other level 1b parameters
  • Other parameters
Heights
Quantity Values Remarks
Units metres (m) a. Ellipsoidal heights (referenced to WGS-84) b. Heights above msl (referenced to geoid EGM96) c. Geopotential heights (referenced to geoid EGM96)
Domain 0-50 km (NRT), 0-80 km (Offline) Surface to 1 hPa, Surface to 0.01 hPa
Range 0-80,000 m
Precision 1 m
Vertical sampling N/A
Accuracy N/A
Location
Quantity Values Remarks
Units degrees (°) of latitude and longitude Geodetic latitude
Domain Latitude: ±90°, Longitude: ±180° Positive in Northern Hemisphere, positive East of Greenwich
Range Latitude: ±90°, Longitude: ±180°Positive in Northern Hemisphere, positive East of Greenwich
Precision 0.001° ~0.1 km
Vertical sampling N/A
Accuracy 0.01° ~1 km
Date and time, time tag
Quantity Values Remarks
UnitsYear, Month, Day, Hours, Minutes, Seconds, MillisecondsAbsolute: date & time at start of profile in UTC. Time-tag: offset from start of profile
Range 2000-2049 y, 1-12 m, 1-31 d, 0-23 h, 0-59 m, 0-59.999 s 00:00 1 Jan 2000 to 23:59 31 Dec 2049
0-100,000 ms Up to 100 s duration (nominal max. 60 s)
Precision 1 ms
Vertical sampling 5 Hz Nominal time equivalent for time-tag
Accuracy 1 ms

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