Question about forcing data when running a case

[Houhhu]

Hello everyone! I am runnning a I2000Clm50BgcCrop case. The model runs from 1990-2014.
I change some setting in the env_run.xml like:

./xmlchange DATM_CLMNCEP_YR_ALIGN=1990
./xmlchange DATM_CLMNCEP_YR_START=1990
./xmlchange DATM_CLMNCEP_YR_END=2014

The model runs successfully.However, when i checked the atm.log,I find that the initial forcing data read by the model was GSWP3v1 2000.01.nc instead of 1990.01nc.
I attach the atm.log file.

and this is the data_in file:
&datm_nml
decomp = "1d"
factorfn = "null"
force_prognostic_true = .false.
iradsw = 1
presaero = .true.
restfilm = "undefined"
restfils = "undefined"
wiso_datm = .false.
/
&shr_strdata_nml
datamode = "CLMNCEP"
domainfile = "/media/wink/EXTERNAL_USB/CLM/data/inputdata/share/domains/domain.lnd.fv0.9x1.25_gx1v7.151020.nc"
dtlimit = 1.5, 1.5, 1.5, 1.5, 1.5
fillalgo = "nn", "nn", "nn", "nn", "nn"
fillmask = "nomask", "nomask", "nomask", "nomask", "nomask"
fillread = "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET"
fillwrite = "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET"
mapalgo = "bilinear", "bilinear", "bilinear", "bilinear", "bilinear"
mapmask = "nomask", "nomask", "nomask", "nomask", "nomask"
mapread = "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET"
mapwrite = "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET", "NOT_SET"
readmode = "single", "single", "single", "single", "single"
streams = "datm.streams.txt.CLMGSWP3v1.Solar 1990 1990 2014",
"datm.streams.txt.CLMGSWP3v1.Precip 1990 1990 2014",
"datm.streams.txt.CLMGSWP3v1.TPQW 1990 1990 2014",
"datm.streams.txt.presaero.clim_2000 1 1 1",
"datm.streams.txt.topo.observed 1 1 1"
taxmode = "cycle", "cycle", "cycle", "cycle", "cycle"
tintalgo = "coszen", "nearest", "linear", "linear", "lower"
vectors = "null"
/
and the file datm.streams.txt.CLMGSWP3v1.Precip is attached below.
<fieldInfo>
<variableNames>
PRECTmms precn
</variableNames>
<filePath>
/media/wink/EXTERNAL_USB/CLM/data/inputdata/lmwg/atm_forcing.datm7.GSWP3.0.5d.v1.c170516/Precip
</filePath>
<fileNames>
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-01.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-02.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-03.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-04.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-05.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-06.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-07.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-08.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-09.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-10.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-11.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1990-12.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-01.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-02.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-03.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-04.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-05.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-06.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-07.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-08.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-09.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-10.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-11.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.1991-12.nc
.........
........
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-01.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-02.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-03.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-04.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-05.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-06.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-07.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-08.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-09.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-10.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-11.nc
clmforc.GSWP3.c2011.0.5x0.5.Prec.2014-12.nc
</fileNames>
<offset>
0
</offset>
</fieldInfo>

 

[oleson]

You specified that you wanted model year 1990 to line up with 1990 forcing. And your model start year is 0001. The datm is going to calculate how to accomplish lining up model year 1990 with 1990 forcing. So it will calculate which forcing year to start with so that it ends up with 1990 aligning with 1990, as it repeats 1990-2014 forcing.