Bias Correction NetCDF-Data by multiplying daily data with a corresponding monthly constant
Added by Thomas Steudel about 10 years ago
Hello,
i have a question. I have timeseries data of monthly observations of precipitation (Station Data) as well as monthly and daily data of ERA40 precipitation sums (nc-Format).
Based on these datasets, I extracted a correction factor (ratio betwen long term monthly precipitation sum and ERA40 long term monthly precipitation sum). Now i have 12 Values(January, .....December) and i want to correct my daily ERA40 Data with the monthly values by multiplying.
The problem:
How do i select all days within the month of January and multiply them by the Bias-Correction Factor?
Does anybody has an idea how to deal with this task?
Thank you very much for answers,
kind regards,
Thomas
Replies (2)
RE: Bias Correction NetCDF-Data by multiplying daily data with a corresponding monthly constant - Added by Uwe Schulzweida about 10 years ago
Hi Thomas,
Try the CDO operator ymonmul. The second input file is a monthly climate, 12 time steps. The trick is to enlarge the station data (one data value) to the size of the ERA40 variables. This can be done with enlarge:
cdo ymonmul ifile1 -enlarge,ifile1 ifile2 ofile
Cheers,
Uwe
RE: Bias Correction NetCDF-Data by multiplying daily data with a corresponding monthly constant - Added by Thomas Steudel about 10 years ago
Hi Uwe,
thank you very much! Looks like the solution for my problem! But what do you mean with "The second input file is a monthly climate"? I only stored the 12 values within an excel file. So i do not have ifile2. Is it possible to use a constant insteat of ifile2? I am a CDO newbe sorry.
Will try tomorrow when back at work!
Thanks and regards from Jena,
Thomas