How do I change query parameters in Ember?

I'm writing an action handler in route:application:

actions: {
  changeFoo(foo) {
    // I want to change the fooId queryParam to foo.get('id')
  }
}

The problem is that the only documented ways I can find to change the query params are transitionTo('some.route', someModel, { queryParams: { ... } } and the replaceWith version of the same. But I'm in route:application, so I don't know the current route's name. That means I don't know what the first argument to transitionTo would be.

Is there another way to get the URL to become ?fooId=123?