Dear Ferret users,
I calculated the temporal derivative of SST for a seasonal cycle
(monthly values) and I think that it induces a one month lag which
seems to be an artefact of the derivative method (centered derivative
@DDC).
Does anyone already had this kind of problem?
To solve that, I wanted to find the polynomial (f(t)=At^3+Bt^2+Ct +D)
that best fit my data, then calculate the derivative function
(f'(t)=3At^2+2Bt+C) and work with f'(t).
So come my questions:
- Does it make sense that calculating a temporal derivative could
induce a lag that is a artefact of the method (centered derivative)?
- How can I find, using Ferret, the polynomial that best fit my function?
Thank you very much in advance for your help,
Kind regards,
Fabrice