Time stamp for pixels in SMOS

Hi everyone:
I’m comparing SMOS AUX parameters with others. So I tried to convert SM_OPER_AUX_ECMWF_*.zip files to NetCDF4-CF. However, I can’t find any information about the time of each pixel except the filename. I even tried to convert it to another format but failed. How to get timestamps of pixels like the ones in SNAP??


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Dear andych1977,

the SMOS ECMWF auxiliary files as they are provided by ESA do not contain any per-pixel time information. Instead they are composed from ECMWF forecast data which is - as far as I know - for SMOS derived from the ERA-INTERIM dataset with a time granularity of 6 hours.

The pixel-time displayed in SNAP is linearly interpolated using the product header paramters “Precise_Validity_Start” and “Precise_Validity_Stop”. As in the case of ECMWF data, this is an incorrect approach, there is no pixel time; the data is derived from model-calculations. We probably should add a flag that indicates this and suppresses the time-interpolation for non-satellite data.

Hope this clarifies the situation.

Tom