Any individual body (thing) has an “infinite” number of different values of kinetic energy and gravitational potential energy, assuming that there are an “infinite” number of other bodies in the universe.
I am sitting at rest at a fixed table. My k.e. with respect to the table and the earth is zero. My g.p.e with respect to the chair-seat is zero.
The earth is moving towards a “stationary” planet at a speed of 20km per second, several parsecs distant. My k.e. with respect to the planet is enormous. My g.p.e with respect to the planet is also huge, as I would have the opportunity to accelerate to a very high speed before I hit it, should I be unlucky enough to fall towards it, without any other outside influence acting on me.
It’s helpful to ignore all these other possible frames of reference when discussing movement within a parcel of air.
Of course, the real atmosphere is untidy and non-uniform, especially close to the ground. Accelerations and turbulence take place, but we must try to keep a clear mind.