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Using angle-resolved X-ray photoelectron spectroscopy, sum-frequency generation vibrational spectroscopy, contact angle measurements, and molecular dynamics simulations, we verify that the glass transition temperature (T_g) of polymer glass is lower near the free surface. However, the experimentalT_g-gradients showed a linear variation with depth (z) from the free surface, while the simulated equilibriumT_g-gradients exhibited a double exponentialz-dependence. In typical simulations,T_gis determined based on the relaxation time of the system reaching a prescribed threshold value at equilibrium. Conversely, the experiments determinedT_gby observing the unfreezing of molecular mobility during heating from a kinetically arrested, nonequilibrium glassy state. To investigate the impact of nonequilibrium effects on theT_g-gradient, we reduced the thermal annealing time in simulations, allowing the system to fall out of equilibrium. We observe a decrease in the relaxation time and the emergence of a modifiedz-dependence consistent with a linearT_g-gradient near the free surface. We further validate the impact of nonequilibrium effects by studying the dependence of theT_gon the heating/cooling rate for polymer films of varying thickness (h). Our experimental results reveal significant variations in theT_g-heating/cooling rate dependence withhbelow the bulkT_g, which are also observed in simulation when the simulated system is not equilibrated. We explain our findings by the reduction in mass density within the inner region of the system under nonequilibrium conditions, as observed in simulation, and recent research indicating a decrease in the localT_gof a polymer when placed next to a softer material.