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Level 1A Data Fields

This table was updated on 12 April 2005 and reflects Version 2 AMSREL1A data. Users are encouraged to work with Version 2 data since they have corrected Cold Sky Mirror (CSM) data and improved geolocation. Data field descriptions are still available for users of Version 1 data.

The following notations are used throughout this document:

Double: 64-bit double-precision floating point
Float32: 32-bit (4-byte) floating point
Int8: 8-bit (1-byte) signed integer
Int16: 16-bit (2-byte) signed integer
Int32: 32-bit (4-byte) signed integer
Uint8: 8-bit (1-byte) unsigned integer
Uint16: 16-bit (2-byte) unsigned integer


Field Type Dimension Per Scan Units Scale Factor
Position_in_Orbit Double 1   1
6GHz-V_Observation_Count_Data Int16 243 count 1
6GHz-H_Observation_Count_Data Int16 243 count 1
10.65GHz-V_Observation_Count_Data Int16 243 count 1
10.65GHz-H_Observation_Count_Data Int16 243 count 1
18.7GHz-V_Observation_Count_Data Int16 243 count 1
18.7GHz-H_Observation_Count_Data Int16 243 count 1
23.8GHz-V_Observation_Count_Data Int16 243 count 1
23.8GHz-H_Observation_Count_Data Int16 243 count 1
36.5GHz-V_Observation_Count_Data Int16 243 count 1
36.5GHz-H_Observation_Count_Data Int16 243 count 1
50.3GHz-V_Observation_Count_Data Int16 243 count 1
52.8GHz-V_Observation_Count_Data Int16 243 count 1
89.0GHz-V-A_Observation_Count_Data Int16 486 counts 1
89.0GHz-H-A_Observation_Count_Data Int16 486 counts 1
89.0GHz-V-B_Observation_Count_Data Int16 486 counts 1
89.0GHz-H-B_Observation_Count_Data Int16 486 counts 1
Hot_Load_Count_6_to_52 Int16 16 x 12 count 1
Hot_Load_Count_89 Int16 32 x 4 count 1
Cold_Sky_Mirror_Count_6_to_52 Int16 16 x 12 count 1
Cold_Sky_Mirror_Count_89 Int16 32 x 4 count 1
Antenna_Temp_Coef(Of+Sl) Float32 32 K+K/count 1
Rx_Offset/Gain_Count Uint16 32 count 1
Navigation_Data Float32 6 m, m/s 1
Attitude_Data Float32 3 deg 1
Lat_of_Observation_Point_Except_89B Int16 486 deg 0.01
Long_of_Observation_Point_Except_89B Int16 486 deg 0.01
Lat_of_Observation_Point_for_89B Int16 486 deg 0.01
Long_of_Observation_Point_for_89B Int16 486 deg 0.01
Sun_Azimuth Int16 243 deg 0.1
Sun_Elevation Int16 243 deg 0.1
Earth_Incidence Int8 243 deg 0.02 with offset of 55°
Earth_Azimuth Int8 243 deg 0.01
Land/Ocean_Flag_for_6_10_18_23_36_50_89A Uint8 243 x 7 percent 1
Observation_Supplement Uint16 27   1
SPC_Temperature_Count Int16 20 count 1
SPS_Temperature_Count Int16 32 count 1
Data_Quality Float32 128   1
Interpolation_Flag_6_to_52 Int8 16 x 12   1
Interpolation_Flag_89 Int8 32 x 4   1
Spill_Over Float32 243 x 200 x 2 mV 1
Scan_Time Double 1 TAI93 (seconds since midnight, 01 January 1993) N/A