Remove Fill Value or Missing Value from Netcdf

If 1e30 is meant to represent NA, I would definitely replace it with NA. To give you detailed advice, it would be very helpful if you posted a Reproducible Example (Reprex). Since your problem has to do with doing calculations, I think you can do the Reprex by defining a small data frame containing a few rows of typical values of your data and then show how you do calculations on that. Here is a link to help you: