Standard Names For Satellite Observations
From Earth Science Information Partners (ESIP)
The Climate and Forecast (CF) metadata convention maintains a list of standard names for data stored in variables of a netCDF file. Not many standard names in that list are relevant to satellite observation data so additional names are proposed here. The new names and accompanying information will follow the CF guidelines.
Proposed Names
Submitter: Global Space-based Inter-Calibration System
| Proposed Standard Name | Canonical units | Definition | Comments/Questions |
| instrument_channel_identifier | Not Applicable | Alphanumeric identifier of instrument's channel. | |
| datetime_iso8601 | Not Applicable | String containing date-time information in one of the ISO 8601 formats. Variables with this standard name cannot serve as coordinate variables. | |
| instrument_zenith_angle | degree | The angle between the line of sight to the instrument and the local vertical. | |
| satellite_scan_angle | degree | The angle between the line of sight from the satellite and the nadir line. Nadir is the direction given by the vertical from the satellite looking towards the center of the Earth. | |
| instrument_azimuth_angle | degree | The horizontal angle between the line of sight to the instrument and a reference direction which is often due north. The angle is measured clockwise. | |
| relative_instrument_azimuth_angle | degree | Difference between two instrument_azimuth_angle values. | |
| time_interval | s | An interval of time. | |
| toa_outgoing_spectral_radiance | mW m-2 sr-1 (cm-1)-1 | "toa" means top of atmosphere; "outgoing" means emitted toward outer space; "spectral" means per unit wavenumber or as a function of wavenumber. Radiance is the radiative flux in a particular direction, per unit of solid angle. | |
| toa_outgoing_spectral_radiance_mean_within_collocation_scene | mW m-2 sr-1 (cm-1)-1 | An average of toa_outgoing_spectral_radiance observations within a collocation scene. Collocation scene is a grouping of instrument's adjacent field of views (FOVs) centered on a collocation target. Collocation target is an area on the Earth's surface at which observations from at least two instruments are collected. Its size is defined by the instrument with the largest FOV footprint. Collocation scene's size is typically about an order of magnitude larger than its collocation target. | |
| toa_outgoing_spectral_radiance_stdev_within_collocation_scene | mW m-2 sr-1 (cm-1)-1 | Standard deviation of toa_outgoing_spectral_radiance observations within a collocation scene. Collocation scene is a grouping of instrument's adjacent field of views (FOVs) centered on a collocation target. Collocation target is an area on the Earth's surface at which observations from at least two instruments are collected. Its size is defined by the instrument with the largest FOV footprint. Collocation scene's size is typically about an order of magnitude larger than its collocation target. | |
| toa_outgoing_spectral_radiance_mean_within_collocation_target | mW m-2 sr-1 (cm-1)-1 | An average of toa_outgoing_spectral_radiance observations from instrument's adjacent field of views within a collocation target. Collocation target is an area on the Earth's surface at which observations from at least two instruments are collected. Its size is defined by the instrument with the largest field of view footprint. | |
| toa_outgoing_spectral_radiance_stdev_within_collocation_target | mW m-2 sr-1 (cm-1)-1 | Standard deviation of toa_outgoing_spectral_radiance observations from instrument's adjacent field of views within a collocation target. Collocation target is an area on the Earth's surface at which observations from at least two instruments are collected. Its size is defined by the instrument with the largest field of view footprint. | |
| linear_term_of_spectral_radiance_correction_due_to_intercalibration | 1 | Linear term (slope) of the formula for correcting measured spectral radiance. The correction is derived from intercalibration between the monitored and the reference instrument. The resulting corrected spectral radiance of the monitored instrument becomes comparable with measured spectral radiance of the reference instrument. "Spectral" means per unit wavenumber or as a function of wavenumber. Radiance is the radiative flux in a particular direction, per unit of solid angle. | |
| constant_term_of_spectral_radiance_correction_due_to_intercalibration | mW m-2 sr-1 (cm-1)-1 | Constant term (offset) of the formula for correcting measured spectral radiance. The correction is derived from intercalibration between the monitored and the reference instrument. The resulting corrected spectral radiance of the monitored instrument becomes comparable with measured spectral radiance of the reference instrument. "Spectral" means per unit wavenumber or as a function of wavenumber. Radiance is the radiative flux in a particular direction, per unit of solid angle. | |
| covariance_between_constant_and_linear_terms_of_spectral_radiance_correction | mW m-2 sr-1 (cm-1)-1 | Covariance between constant_term_of_spectral_radiance_correction_due_to_intercalibration and linear_term_of_spectral_radiance_correction_due_to_intercalibration values. | |
| toa_brightness_temperature_of_standard_scene | K | "toa" means top of atmosphere. Brightness temperature of a body is the temperature of a black body which radiates the same power per unit solid angle per unit area. Standard scene is a physical model of the Earth surface and atmosphere that is accepted as a reference. This model is used in a radiative transfer simulation to calculate top-of-atmosphere radiance for a given viewing geometry. The resultant top-of-atmosphere radiance is then integrated with an instrument's spectral response function and converted to equivalent brightness temperature. | |
| toa_brightness_temperature_bias_at_standard_scene_wrt_intercalibration | K | The difference between intercalibrated simulated top-of-atmosphere (TOA) brightness temperature of the reference instrument and simulated TOA brightness temperature of the monitored instrument. Intercalibration is a process of deriving an equation by which observations from the monitored instrument become comparable to observations from the reference instrument. This difference is a measure of the quality of intercalibration. Standard scene is a physical model of the Earth surface and atmosphere that is accepted as a reference. Brightness temperature of a body is the temperature of a black body which radiates the same power per unit solid angle per unit area. TOA brightness temperatures for both the monitored and referenced instruments are calculated using the standard scene model and a radiative transfer simulation. The resultant top-of-atmosphere radiance is then integrated with each instrument's spectral response functions and converted to equivalent brightness temperature. |
Testing alternative display:
| Standard name | instrument_channel_identifier |
| Canonical units | N/A |
| Definition | Alphanumeric identifier of instrument's channel. |
| Standard name | toa_brightness_temperature_bias_at_standard_scene_wrt_intercalibration |
| Canonical units | K |
| Definition | The difference between intercalibrated simulated top-of-atmosphere (TOA) brightness temperature of the reference instrument and simulated TOA brightness temperature of the monitored instrument. Intercalibration is a process of deriving an equation by which observations from the monitored instrument become comparable to observations from the reference instrument. This difference is a measure of the quality of intercalibration. Standard scene is a physical model of the Earth surface and atmosphere that is accepted as a reference. Brightness temperature of a body is the temperature of a black body which radiates the same power per unit solid angle per unit area. TOA brightness temperatures for both the monitored and referenced instruments are calculated using the standard scene model and a radiative transfer simulation. The resultant top-of-atmosphere radiance is then integrated with each instrument's spectral response functions and converted to equivalent brightness temperature. |
