SMPPD - SMOS Level 2 Soil Moisture Prototype Processor Development
Artist’s impression of SMOS in orbit. Source: CESBIO
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’s participation in SMOS started in January 2005 and has continued to this day. Collaborating with Array on this project are several world renowned scientific research institutes, including :
- CESBIO of France
- IPSL/SA of France
- INRA Ephyse of Bordeaux/France
- University of Rome, Tor Vergata of Italy
Array’s major contributions to SMOS include the development of the Level 2 Soil Moisture (L2SM) Prototype Processor, the Core Operational Processor, and the auxiliary data products required for the operations of these processors. Furthermore Array has also supported the science teams in the development and validation of scientific algorithms used in the processors.
The L2SM processor is designed to retrieve soil moisture, vegetation optical thickness, and other geophysical parameters of interest from SMOS L-Band telemetry. Array is currently part of the SMOS commissioning team leading the L2SM product verification and supporting ESA's commissioning activities.
Soil Moisture Processing Overview
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 following figure 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.
Click here to visit ESA SMOS website for details.