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Offline Sounding Data Products

The main parameters in the Offline data products are identical (apart from the Bending Angle product) to those contained in the NRT Data Products. The Offline Data Products have been processed to a different specification than the NRT Data Products, including reprocessed satellite orbits. The Offline products, improved compared to the NRT products, are delivered less than 30 days after measurement, making them the choice for climate researchers.

Bending Angle (GRM-08)
Quantity Values Remarks
Units radians (rad)
Domain 0-80 km Surface to 0.01 hPa
Range -0.0001 to 0.05 rad
Precision 0.1 µrad
Vertical resolution150-250 m
Target accuracy 0.4 % or 1 µradwhichever is greater
Refractivity profile (GRM-09)
Quantity Values Remarks
Units Refractivity units (N) Neutral atmosphere
Domain 0-80 km Surface to 0.01 hPa
Range 0-450 N-units
Precision 0.1 N-units
Vertical resolution 150-250 m
Target accuracy 0.5-2 %, 0.5 %, 0.02 N-units0-5 km, 5-30 km, 30-50 km
Temperature profile (GRM-10)
Quantity Values Remarks
Units Kelvin (K)
Domain 0-80 km Surface to 0.01hPa
Range 180-350 K
Precision 0.1 K
Vertical resolution250-500 m depends on background pressure levels
Target accuracy1-2 K, 0.5 K, 0.5-3 K, 3-5 K0-5 km, 5-30 km, 30-40 km, 40-50 km
Specific humidity profile (GRM-11)
Quantity Values Remarks
Units kg/kg Specific humidity
Domain 0-15 km Surface to 100 hPa
Range 0-50 g/kg
Precision 0.001 g/kg
Vertical resolution 250-500 m depends on background pressure levels
Target accuracy 5 % or 0.1 g/kg whichever is greater
Pressure profile (GRM-12)
Quantity Values Remarks
Units hectopascals (hPa)
Domain 0-80 km Surface to 0.01 hPa
Range 0.01-1100 hPa
Precision 0.001 hPa
Vertical resolution 250-500 m depends on background pressure levels
Target accuracy 0.1 % or 1hPa whichever is greater
Surface pressure (GRM-13)
Quantity Values Remarks
Units hectopascals (hPa)
Domain SurfaceHorizontal location nominally at the ellipsoid tangent point location of the straight line connecting GPS and MetOp
Range 900-1100 hPa
Precision 0.001 hPa
Vertical resolution N/A
Target accuracy 1 hPa

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