question about rttov_K #1
Description
Dear author.
This is a text message asking for help.
Hello, I would like to know why RTTOVk still needs to input perturbation when solving jacobian. After reading the code (supporting_routines_m.mergeX_all), it seems that only water vapor uses perturbation values, and what role does this value play?
I am very confused, does this value determine the amount of change in each variable during each iteration? Could you help me explain.