SMOS

Summary

ESA’s Soil Moisture and Ocean Salinity (SMOS) mission is dedicated to making global observations of soil moisture over land and salinity over oceans, two key variables of Earth’s water cycle and recognized Essential Climate Variables. Launched on 2 November 2009 from the Plesetsk Cosmodrome, SMOS is the second mission in ESA’s Earth Explorer programme and the first to deliver global L-band brightness temperature measurements from space.

At its core sits MIRAS, the Microwave Imaging Radiometer using Aperture Synthesis, which is the first space-borne 2-D interferometric radiometer, operating in the protected 1.413 GHz L-band. Originally designed for a five-year lifetime, SMOS continues to deliver critical data more than 15 years after launch, supporting weather forecasting, climate models, sea-ice monitoring, and beyond.

Our contribution

We lead the instrument calibration activity, transforming raw Level 0 data into calibrated Level 1 products and ensuring brightness temperature measurements are physically consistent and scientifically reliable. We also play an active role in tackling one of the mission’s most pressing operational challenges: detection and mitigation of radio-frequency interference (RFI). RFI has become a critical issue for SMOS data quality, particularly in regions affected by jamming systems and conflict-related interference, including parts of Europe and Southeast Asia. Our work helps preserve scientific integrity in an increasingly congested RF environment.

Key activities:

• Level 0 to Level 1 calibration and brightness temperature processing.
• Quality assurance of calibrated data products.
• RFI detection, characterization, and mitigation.
• Long-term monitoring of instrument performance.
• Technical support to ESA and the SMOS scientific community.

Dates

• Launch: 2 November 2009
• Status: Operational (extended mission)
• Our involvement: Ongoing

Partners

• European Space Agency (ESA).
• CNES – joint mission operations.
• CDTI – Spanish national contribution.
• SMOS Expert Support Laboratories and scientific community.

Related links

• SMOS mission page (ESA)
• SMOS on ESA Earth Online
• SMOS Data Processing Ground Segment (ESAC)