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Questions for 1-month WRF simulation


New member
Hi, everyone!
I intend to conduct one-month WRF simulation to indicate the sensitivity of the percipitation to a revised radiation parameterization.
I have three issues about the input data and spin up time.
1. ECMWF or FNL?
Previous studies showd that the ECMWF reanalysis (0.25*0.25;0.75*0.75) is better than FNL (1*1), but some variables in FNL variable lists (Convection, Terrain elevation, Tropopause, etc.,) are not available in ECMWF variable lists. Even these variables are not necessary during model run, the model performance may be doubtful without these variables. I'm confused about which to choose.截屏2022-10-11 下午8.48.21.png
2. NCEP GDAS (ds0833) and FNL (ds0832)
The horizontal resolution of NCEP GDAS (0.25*0.25; ds0833) is higher than that of the FNL (1*1; ds0832). Can I use the 6 hourly NCEP GDAS/FNL (**00.f00.grib2; **06.f00.grib2; **12.f00.grib2; **18.f00.grib2) as input data to do 1-month simulation?
3. Spin-up time
Is two weeks spin up time enough for 1-month simulation?
Thank you for any generous help!
Last edited:
Please see my answers to your questions:
(1) ERA-I and ERA5 both provide all required variables for running WRF. Please take a look at the websites here:
(2) I would recommend using NCEP GDAS/FNL data
(3) Since WRF is regional model strictly constrained by lateral forcing data, spin-up is not a big issue. I don;'t think you need 2 weeks of spin-up time.