Known to work on with Python 2.7 on modern Linux and OS X systems. Not tested on anything else.

One environment variable must be set:

  • SCRATCH - the name of a directory to download weather data to.

Relies on Iris, so first install that.

Uses the ECMWF api: ecmwfapi - to download CERA-20C and ERA5 data. Follow the instructions on that page to get an ECMWF api account (free). You don’t have to install the package (setup will do that - see below), but you do need to an api key. If you are only using 20CR data you can skip this step.

Then download or fork the source in

  • Install with ‘python install –user’.
  • Test with ‘python test’.