We have fixed the issues on the lore server that were preventing the launch button from working properly.
From now on, the best way to access new lecture and assignment notebooks is this:
navigate to the appropriate page in the Climate Laboratory book
Hover over the “Rocket Ship” icon at top right
From the drop-down menu, select “JupyterHub”
If you get prompted to log in to the server, do so and then try to launch link one more time.