Effect of Radio Frequency Interference-Contaminated AMSR2 Signal Restoration on Soil Moisture Retrieval

Soil moisture is a key variable of the climate system. Microwave remote sensing has become an essential means obtaining soil because unique advantages its all-day and all-weather observation capability. Theoretically, low-frequency C-band observations are highly suitable for retrieval their high sensitivity to at vegetation roots. However, quality suffers from radio frequency interference (RFI) over United States. This paper used iterative principal component analysis (PCA) method repair RFI-contaminated second-generation Advanced Scanning Radiometer (AMSR-2) observations, results based on restored data were evaluated. It was found that RFI could lead nonconvergence in large amount data, application repaired result recovery more than 80% nonconvergent especially spring autumn. The attained satisfactory correlation with ERA5 reanalysis European Space Agency Climate Change Initiative (ESA-CCI) suitably agreed precipitation data. generally exhibited gradual increase west north east. feature weakened due influence monsoons east summer. western side Cascade Mountains wettest area States, exceeding 0.4 m3 m−3. driest region States located between Rockies Cordillera Mountains, value lower 0.1