The Soil Moisture Active Passive (SMAP) "Corrected Brightness Temperature" layers display brightness temperatures (TBs) in Kelvin (K) for the vertical (V) polarization from the SMAP radiometer.
The TBs are corrected for the presence of water wherever water fraction is below a threshold. 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. The imagery resolution is 2 km and sensor resolution is 36 km. The temporal resolution is daily.
References: SMAP L3 Radiometer Global Daily 36 km EASE-Grid Soil Moisture
Data field: tb_v_corrected