Author here,<p>The debris is coloured to match the descriptive text.<p>Each years data is loaded when the user gets to that part of the visualisation.<p>The ring you see is indeed all of the satellites in geosynchronous orbit.  You can also see the orbits of many of the GNSS satellites in medium Earth orbit if you stare hard enough for long enough!<p>This shows all objects (functioning and debris) in orbit at the time in question.