Y-coordinates stops working when reaching 2147483647

Once you reach y: 2147483647 the "Block" part of the debug screen can't keep track of your y-coordinates anymore. But the "XYZ" part can.

What I expected to happen was:
The "Block" would keep counting upwards as I flew upwards.

What actually happened:
it didn't.

Steps to reproduce:
1. do /tp ~ 2147483647 ~
2. Go upwards for a while.
3 The y on "XYZ" will continue to go upwards, but the "Block" stays at 2147483647.