The first thing you could do would be to update your model and replace
the one that is on the warehouse of course. This can be quite the
task if you have 1000s of models and every model is perfectly to the
terrain. Knowing this fact now changes the way people should approach
future models. It's a relatively easy fix for smaller foot print
models. If there is extra geometry the goes under the terrain, it
will be less noticeable if the model starts to float on the next
terrain update. This make one think about chopping up larger models
and loading smaller models to the warehouse. There is a clamp to
ground solution in Google Earth and maybe this method will be applied
to future models. If the model takes up a large area, the smaller the
pieces, the less chances there would be sinking or floating areas. I
was always under the assumption that the terrain was updated when new
imagery was released. It seems that terrain releases are separate
than imagery releases. This issue has especially been challenging
since the company I am with (concept3d) makes 1000s of Google Earth
models. I will be posting a blog next week sharing more about this
topic.