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Before the SMOS launch, forecast systems can be used in the product definition phase. Based on modeled modelled atmospheric and land state variables, the effect of different parameterizations and auxiliary data sets on the retrieval can be analysed. In addition, the errors introduced through temporal collocation mismatches between the auxiliary data sets and the actual observations can be quantified.
After the SMOS launch, when real SMOS observations are available, monitoring, i.e. comparison between the modeled modelled equivalent of the observation and the observation itself, makes a significant contribution to the calibration / validation activities. Any systematic error or spikes, become visible and can be reported to ESA and the other calibration and validation teams without significant delays.
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