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Driving Atmosphere with high frequency Ocean SST/CICE

Hello CESM Discuss,

I am executing CESM1.2 and I want to drive the Atmospheric model with sub-daily ocean SSTs. I cannot find where in the docn to change the input from monthly SSTs to 2x daily SSTs. I think this should be possible, because my understanding is that in the fully coupled simulation, the ocean SSTs are read 2x daily.

Thank you,
-Jonathan R. Buzan
Climate and Environmental Physics
Physics Institute
Oeschger Centre for Climate Change Research
University of Bern
Sidlerstrasse 5
3012 Bern, Switzerland


Erik Kluzek
CSEG and Liaisons
Staff member
The temporal frequency of the input data to docn can be at any frequency. It should be at the same frequency throughout, but it can be something different than the default monthly. When the model reads the data in, it reads it in as a CIME stream object, which reads in the data two time samples at a time. It requires the file to have the time stamps on both those time samples, but it doesn't need to know what the temporal frequency is outside of that.
HI Erik,

Thank you for your prompt reply!
I want to make sure I understand this correctly.

All I need to do is source a file that has time dimension is properly defined, and the SST time steps that are sub daily will automatically be read by the docn model?



Cecile Hannay
AMWG Liaison
Staff member
Hi Jonathan,
This is correct. The default SST datasets are monthly. But a SSTs dataset at higher frequency should be automatically read by the docn model assuming the dataset variables are in a format that can be read by CAM. If you mimic the original dataset (variable names, dimension names, etc...) you should be fine
Cecile Hannay and Erik Kluzek,

I have generated SST/ICE files that are daily resolution. However, I keep encountering the same error:
(shr_sys_abort) ERROR: (shr_stream_findBounds) ERROR: LVD not found, all data is after yearLast
(shr_sys_abort) WARNING: calling shr_mpi_abort() and stopping

I am not sure what is incorrect in my file or env_run setup. I have listed examples below for the sst file and the stream from env_run.xml. Perhaps you know what the error is?


My driving dataset file:
float SST_cpl(time, lat, lon) ;
SST_cpl:long_name = "BCS Pseudo SST" ;
SST_cpl:units = "deg_C" ;
float time(time) ;
time:units = "days since 0000-01-01 00:00:00" ;
time:calendar = "365_day" ;
int date(time) ;
date:long_name = "current date (YYYYMMDD)" ;
double ice_cov(time, lat, lon) ;
ice_cov:long_name = "BCS Pseudo Sea-ice concentration" ;
ice_cov:units = "fraction" ;
double lon(lon) ;
lon:long_name = "longitude" ;
lon:units = "degrees_east" ;
double lat(lat) ;
lat:long_name = "latitude" ;
lat:units = "degrees_north" ;

example time:
time = 731, 732, 733, 734, 735, 736,...

example date:
date = 10101, 10102, 10103, 10104, 10105,...

<!--"The model year that corresponds to SSTICE_YEAR_START on the data file. (integer) " -->
<entry id="SSTICE_YEAR_ALIGN" value="1" />

<!--"The first year of data to use from SSTICE_DATA_FILENAME. (integer) " -->
<entry id="SSTICE_YEAR_START" value="1" />

<!--"The last year of data to use from SSTICE_DATA_FILENAME. (integer) " -->
<entry id="SSTICE_YEAR_END" value="1" />

9-Jean Li

New Member
I'm not sure whether the problem is your date fomular isn't consist with your date attribute, which is date:long_name = "current date (YYYYMMDD)" ;
And, LVD is not in your user_nl_* right?