Google Cloud Storage Bucket: XML error when reloading an Ember.js app in GCS

We recently moved an Ember.js app hosted in an Amazon AWS S3 bucket to a Google Cloud Storage Bucket. The app works great when we load the index.html page. Ember transitions work just fine however, when we directly visit a URL that isn't the project's main route (for example, /account-settings) or reload a URL that we are working on, we get the following error:

<Error>
    <Code>NoSuchKey</Code>
    <Message>The specified key does not exist.</Message>
</Error>

My assumption is that this has to do with the request not being handled by the Ember Router and index.html? I couldn't find any solutions to fix this in the Google Cloud documentation. How can I fix this?