Is there any way to clear out my busy airport so I can upgrade it?

I really want to upgrade this airport, because it's causing some big backlogs for me. However, it's so busy that there are constantly airplanes either loading/unloading, in the hangar waiting or circling to land. This means I can't delete to rebuild. Is there any way I can clear it out temporarily to allow me to demolish/rebuild?

When you click on the airport, in the details screen there is a 'Close Airport' button. Next to the 'Rename Airport' button I believe.

This will stop planes from landing (it'll skip the destination in their orders) which lets you do the in situ upgrade.

You can try to have all the planes dock somewhere else, which would take a lot of time.

A possibly easier thing to do is to build a temporary airport to accomodate a place for the aircraft to be during the upgrade. What I mean with that is that you replace this airport with the temporary airport in the airplanes directions.