Potential energy relative to the surface is
(mass) x (acceleration due to gravity) x (height above the surface).
At 1.0 meter above the surface, that is
(mass) x (acceleration due to gravity) x (1.0 meter) .
The object's mass doesn't change, so the only thing that has any effect
on its potential energy at 1 meter above the surface is the acceleration
of gravity or, in other words, the surface of what ?