Here’s an instruction on how to disable google calendar :
1. Go to Google Calendar and click “Settings”:
2. On Calendar Settings, choose “Calendars”
3. Then choose your calendar “Notifications”
4. On Event reminders, click “remove” on the pop-up event option (see below).
And then click “Save” button.
You should be all set and now will not have anymore “pop-up” reminders.