A New Method to Filter Out Radio-Frequency Interference (RFI) from SMOS Level 1C Data for Sea Ice Applications - Towards an Interdisciplinary Approach in Earth System Science - page 89

As we expect a normal distribution, other methods than just the standard devi-
ation as criteria could be employed, such as Dixon ' s Q test (Dean and Dixon 1951 )

or Grubbs test (Grubbs 1950 ) for outlier elimination or replacing the currently

taken mean by median. An alternative

'

fit the brightness
temperature as a function of incidence angle potentially based on the Fresnel
equations and de

filter method would be to

ne an additional parameter to re fl ect the quality of each t.

However, for the purpose of RFI removal, the described filtering procedure has

proved satisfactory for the 3 month of Oct Dec 2010.

-

Acknowledgments Financial support of the Federal Ministry of Education and Research/Bun-
desministerium f für Bildung und Forschung (BMBF) MiKliP project Climate Model Validation by

confronting globally Essential Climate Variables from models with observations (ClimVal) is
gratefully acknowledged. We also thank the reviewers for

ü

their valuable comments and

suggestions.

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