Temporal coverage: 31 March 2015 - present
The Soil Moisture Active Passive (SMAP) "Uncorrected Brightness Temperature 36 km" layers display brightness temperatures (TBs) posted to a 36 km EASE-Grid 2.0 and uncorrected for the presence of water in Kelvin (K) for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer. At the L-band frequency used by SMAP, the TB of the land surface is proportional to its emissivity multiplied by its physical temperature.
The SMAP spacecraft carries two instruments, a radar (active) and a radiometer (passive), that together make global measurements of land surface soil moisture and freeze/thaw state. It is useful for monitoring and predicting natural hazards such as floods and droughts, understanding the linkages between Earth’s water, energy and carbon cycles, and reducing uncertainties in predicting weather and climate.
References: SMAP L1C Radiometer Half-Orbit 36 km EASE-Grid Brightness Temperatures
Data fields: celltbhfore, celltbhaft, celltbvfore, celltbvaft
Temporal coverage: 31 March 2015 - present
The Soil Moisture Active Passive (SMAP) "Uncorrected Brightness Temperature 36 km QA” layers display quality assurance (QA) flags for uncorrected brightness temperatures (TBs) on a 36 km EASE-Grid 2.0 for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer.
Within the image, green indicates that TB observations have acceptable quality for science use, yellow indicates that caution should be used with the TB observations as one or more quality-impacting conditions have been identified, and red indicates that TB observations are flagged as bad due to unacceptable quality.
The Soil Moisture Active Passive (SMAP) "Uncorrected Brightness Temperature 36 km RFI” layers displays Radio Frequency Interference (RFI) quality flags of uncorrected brightness temperatures (TBs) on a 36 km EASE-Grid 2.0 for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer. RFI refers to the interference in measurements from other transmitters operating at frequencies adjacent to the SMAP L-band frequency.
Within the image, green indicates that TB observations are free of RFI and approved for science use, yellow indicates that caution should be used with the TB observations as RFI was detected but mitigated, and red indicates that TB observations are flagged as bad due to RFI.
References: SMAP L1C Radiometer Half-Orbit 36 km EASE-Grid Brightness Temperatures
Data fields: cell_tb_qual_flag_h_fore, cell_tb_qual_flag_h_aft, cell_tb_qual_flag_v_fore, cell_tb_qual_flag_v_aft
Temporal coverage: 31 March 2015 - present
The Soil Moisture Active Passive (SMAP) "Uncorrected Brightness Temperature 9 km" layers display brightness temperatures (TBs) uncorrected for the presence of water in Kelvin (K) for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer. To enhance the grid resolution, Backus-Gilbert optimal interpolation techniques are used to extract maximum information from SMAP antenna temperatures and convert them to brightness temperatures, which are posted to the 9 km EASE-Grid 2.0 in a global cylindrical projection. At the L-band frequency used by SMAP, the TB of the land surface is proportional to its emissivity multiplied by its physical temperature.
The SMAP spacecraft carries two instruments, a radar (active) and a radiometer (passive), that together make global measurements of land surface soil moisture and freeze/thaw state. It is useful for monitoring and predicting natural hazards such as floods and droughts, understanding the linkages between Earth’s water, energy and carbon cycles, and reducing uncertainties in predicting weather and climate.
References: SMAP Enhanced L1C Radiometer Half-Orbit 9 km EASE-Grid Brightness Temperatures
Data fields: cell_tb_h_fore, cell_tb_h_aft, cell_tb_v_fore, cell_tb_v_aft
Temporal coverage: 31 March 2015 - present
The Soil Moisture Active Passive (SMAP) "Uncorrected Enhanced Brightness Temperature 9 km QA” layers display quality assurance (QA) flags for uncorrected brightness temperatures (TBs) posted to a 9 km EASE-Grid 2.0 for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer.
Within the image, green indicates that TB observations have acceptable quality for science use, yellow indicates that caution should be used with the TB observations as one or more quality-impacting conditions have been identified, and red indicates that TB observations are flagged as bad due to unacceptable quality.
The Soil Moisture Active Passive (SMAP) "Uncorrected Brightness Temperature 9 km RFI” layers displays Radio Frequency Interference (RFI) quality flags of uncorrected brightness temperatures (TBs) posted to a 9 km EASE-Grid 2.0 for the horizontal (H) and vertical (V) polarizations of the fore and aft scans from the SMAP radiometer. RFI refers to the interference in measurements from other transmitters operating at frequencies adjacent to the SMAP L-band frequency.
Within the image, green indicates that TB observations are free of RFI and approved for science use, yellow indicates that caution should be used with the TB observations as RFI was detected but mitigated, and red indicates that TB observations are flagged as bad due to RFI.
References: SMAP Enhanced L1C Radiometer Half-Orbit 9 km EASE-Grid Brightness Temperatures
Data fields: cell_tb_qual_flag_h_fore, cell_tb_qual_flag_h_aft, cell_tb_qual_flag_v_fore, cell_tb_qual_flag_v_aft