v0.8.5

This is a minor release that deals with clean up issues on Jupyter notebooks. A change in a recent version of ipykernel was causing nctoolkit to not automatically remove temporary files on exit when using notebooks. This should now be fixed.

The annual_anomaly method now lets users temporally align the output, in the same way as other temporal methods such as roll_mean.

Some improvements have been made to internals for better warnings and errors.