ROMS-4DVar is not assimilating observations!

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Biswamoy_Paul
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Joined: Sat Oct 18, 2014 4:11 pm
Location: INCOIS, Hyderabad, INDIA

ROMS-4DVar is not assimilating observations!

#1 Post by Biswamoy_Paul » Thu May 17, 2018 2:00 pm

Hello,
I am in process of implementing incremental strong constraint ROMS-4DVAR (I4D-Var) for the operational forecast of Indian Ocean. I have successfully tested the WC13 configuration in our cluster. Now I am trying to setup ROMS-4DVAR for the Indian Ocean with 1/12 deg resolution and 40 vertical levels.
In this regards, I have downloaded MetOffice Levitus et al profiles data (Temp and Salt) from http://hadobs.metoffice.com/en4/download-en4-2-1.html and prepared ROMS observations for Aug 2016 with Matlab script d_ts_metoffice.m provided with ROMS. I also prepared monthly standard deviation files for initial condition, surface forcing and boundary condition with d_std.m, d_std_frc.m and d_std_bry.m respectively. I made sure that the ocean_time for std files and obs_time/survey_time for obs file match with that of the model initial file.
Then I moved to Normalization directory and computed the error covariance normalization factors using the randomization approach.
Now I am trying to run I4DVAR for 15 days with the initial file on 15-AUG-2016. But here I am surprised to see that the model is not assimilating the observations at all! :o It is running like ROMS without any assimilation. The output it gives are io_fwd_000.nc, io_rst.nc and io_mod.nc only. The ROMS log file (4dvar.out.dat, attached) shows that it doesn't even read the observations. Though it is reading those STD and NRM files.
Is the format of ROMS observation file correct (attached a ncdump'ed file of obs, io_ts_super_obs.nc.in)? Or the procedure I followed is wrong somewhere? I have attached necessary scripts and outputs for your references. Any kind of help or advice would be highly appreciated. Thanks in advance. :)
Biswamoy Paul
Attachments
4dvar.out.dat
Output log of I4DVAR run
(6.79 MiB) Downloaded 71 times
i4dvar.in
I4DVAR input script
(43.39 KiB) Downloaded 84 times
i4dvar.build.bash
The build.bash for I4DVAR
(18.3 KiB) Downloaded 67 times
ocean_io_1x12.in
ROMS input file for Normalization and I4DVAR
(133.01 KiB) Downloaded 74 times
norm.out.dat
Output log of Normalization run
(155.76 KiB) Downloaded 70 times
c4dvar.in
Normalization input script
(43.39 KiB) Downloaded 67 times
norm.build.bash
The build.bash for Normalization
(18.85 KiB) Downloaded 64 times
io_1x12.h
Headers file I used for Normalization and I4DVAR compilation
(4.79 KiB) Downloaded 70 times
io_ts_super_obs.nc.in
The super obs I prepared from met office EN4 profiles
(2.56 KiB) Downloaded 75 times

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