The Soil Moisture Active Passive (SMAP) "Sigma0 3 km RFI (L3, Active, VV Polarization)" layer displays Radio Frequency Interference (RFI) quality flags of backscatter posted on a 3 km EASE-Grid 2.0 for the vertical transmit and the vertical receive (VV) polarizations from the SMAP radar. RFI refers to the interference in measurements from other transmitters operating at frequencies in and adjacent to the SMAP L-band frequency.

Within the image, green indicates that Sigma0 observations are free of RFI and approved for science use, yellow indicates that caution should be used with the Sigma0 observations as RFI was detected but mitigated, and red indicates that Sigma0 observations are flagged as bad due to RFI.

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 L3 Radar Global Daily 3 km EASE-Grid Soil Moisture

Data field: sigma0_qual_flag_vv