SMOS Level 2 Soil Moisture processor
The European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite launched in November 2009 is designed to observe soil mositure over the landmasses and salinity over the oceans. These key parameters play a vital role in understanding the Earth's climate. Array with the support of the Expert Support Laboratories, listed below, is responsible for the development, evolution, and maintenance of the SMOS Level 2 (L2) Soil Moisture (SM) processors, their associated Auxiliary Data Files (ADFs), and the SMOS Matlab Read API.
The L2SM processor is designed to retrieve soil moisture, vegetation optical thickness, and other geophysical parameters of interest from SMOS L-Band telemetry. The SMOS Level 2 Ocean Salinity processor, from ARGANS, retrieves salinity over oceans.
SMOS L2SM processor’s main function is the estimation of soil moisture and other geophysical parameters of interest based on the multi angular brightness temperatures observed by SMOS. The geophysical parameters are computed for a set of Earth-fixed grid points known as Discrete Global Grid (DGG). The processor uses a set of mathematical models to compute the L-Band emission for a given target as observed by SMOS. The modeling needs to take into account the surface characteristics of the target itself as well as the vegetation cover and the atmosphere on top. The figure on the left depicts the main function of the L2SM processor.
A key characteristic of the SMOS L2SM processor is its flexibility in incorporating new L-Band emission models, allowing scientists to experiment with different models and choose the one best suited for their studies.
In addition the processor uses a flexible grid for several of its input products, allowing scientists to improve the quality of retrieved parameters by using data at higher resolutions when available.