Global AJAX Error Handler in ember.js

I'm building an Ember application that has a lot of integration with a back-end API, so I'd like to set up a global AJAX error handler to display to the user if AJAX requests fail. How do I set up a global AJAX error handler in ember.js?

So far, I have an errorController:

MyApplication.ErrorController = Ember.ObjectController.extend({
    errorTitle:"",
    errorDescription:"",
    actions: {
        backToHome: function() {
            this.transitionToRoute('home');
        }
    }
});

And I'm trying to use jQuery's ajaxError function to capture an AJAX failure:

Ember.$(document).ajaxError(function(event, jqXHR, ajaxSettings, thrownError) {
    var errorController = MyApplication.controllerFor('error');
    errorController.set('errorHeading', 'AJAX error');
    errorController.set('errorDescription', jqXHR.responseText); //server will return the error description
    MyApplication.transitionToRoute('error');
});

However, controllerFor doesn't exist in the MyApplication variable. I'm not sure what other way to access ErrorController since the error function is completely out of the scope of the Ember application.