Negative Values in ERA5 Precipitation Data


I have downloaded a daily ERA5 Precipitation data and merged its parts in CDO.

Then took a dailysum and saw that there were negative precipition values.

Why can this be?

Thanks in advance,


Hi Emre, if you are downloading the data in netCDF format, then this can happen due to the GRIB to netCDF conversion used; very small positive values in the GRIB file can appear as small negative values in the netCDF file. In this case, such negative values should be treated as zero.

Alternatively, you can use the GRIB files directly, so you should not see any negative values.

Hope that helps. Thanks,