By default, the data hub provides four relaxation files per day (one every six hours). Is it possible to request hourly relaxation files from the data hub?
Thank you for the help,
Jordan Seneca
Hi Jordan,
Sorry, no this is not possible at this time. The data is only available at 6 hourly intervals I’m afraid. Why are you looking for such high frequency relaxation data?
Many thanks,
Marcus
Hi Marcus, thank you for your reply.
This is for the application of the tuning algorithm we’re working on here at KNMI. It works with OIFS running in a nudged configuration, but the default relaxation scheme does a linear interpolation between two relaxation files 6 hours apart, which causes some issues with the algorithm. Removing the interpolation and using a strong relaxation every 6 timesteps directly to the relaxation file fixes this issue when using pseudo-data (which were made with a OIFS free run).
I was advised by Inna Poulichtchouk to use hourly relaxation files if attempting the same with ERA5 data to avoid shocks, which would occur if adjusting every 6 hours.
I already have a script to format OIFS output into relaxation files, hopefully the same can be achieved with ERA5 data procured by the usual sources.
Best regards,
Jordan
EDIT: Actually, what steps need to be taken to produce relaxation files from ERA5?