Apple - Can't turn off email alerts for events in Yosemite

This worked for me:

Open Calendar on your Mac.

In the left column list of calendars, right click (or command-I) on the calendar in question and "Get Info"

Check the box labeled "Ignore alerts"

Hit "OK"

This is an old post but might be helpful for some.

It turns out, as far as I can tell, that the alert emails originating from the Mac mail app are just following the instructions you have programmed on Google Calendar, much like pop up notifications work.

That being said, as of now, there is no way to ignore than instruction from google calendar unless you remove all alerts from your mac (which also would turn off the pop up alerts, which may or may not be acceptable) or to disable the email alerts from the google calendar side (which will also eliminate the emailed alerts from google, which again, may or may not be acceptable)

Or the third option is to live with the duplicates until apple decides to give us an option to ignore email alert settings from google calendar to avoid having a duplicate.

Hope that's clear and makes sense.

I had called Apple Support and they could not resolve anything either.

I figured it out.

1. Open Google Calendar on your computer in a browser.
2. In the top right, click the gear button, then click Settings in the drop down menu
3. At the top of the Settings page, click the Calendars tab.
4. Next to your calendar's name, click Edit notifications.
5. Once on this page you can remove or edit any default notifications. Correct if i'm wrong but you should see a notification in your list that looks like this:

5. Just remove that notification or change it to a different kind of notification (the only other option besides 'Email' is just a regular 'Notification) and you should be all good.