CDO

Hello!

I have 10 years of daily data, divided into one nc-file for every 10 days. I would like to compute mean EKE, and eddy fluxes(the model gives daily outputs for U*theta, V*theta etc...) from this data. I had planned on doing this in fortran, but then I just discovered CDO, and it seemed like a very nice alternative. Being totally new to this, I was wondering if anyone could give me some advice how to best go around this?

1. First I thought I could merge the 10day-files into new nc-files, each containing one year, and then use the seasonal mean. Do I use merge or mergetime for this? My concern is though, that some of the files overlap, and contain days from two different years.. would it be better(or is it even possible-concerning the size) to merge all the ~360 files into one huge one? Then I could perhaps use multiyear seasonal mean, and also selmon selyear etc. to make seasonal means within a year?

2. Once I have the mean fields I thought I could use CDO expr to compute the mean EKE (sqrt(<u^2> - <u>^2)), any heads-up on what can become an issue there? I read about some trouble regarding land/ocean-mask value, and the need to use -setvrange.. Was this maybe a particular case, or do I need to set a range for the variables before taking the mean? I also know I have at least one corrupt file - how to deal with missing data?

Sorry for the bombardment of questions! Answers to any of them are recieved with huge gratitude! Thanks in advance!

- Marta