A 52-level time-dependent radiative-convective-conductive heat transfer model, paired with a 30-level ground conduction subroutine and a detailed soil-atmosphere heat balance equation, is applied to heavy and slight dust-laden atmospheric conditions on Mars. High spectroscopic, spatial, and temporal resolution is necessary to approximate the thermal structure of the atmospheric surface boundary layer under both conditions. The results show that heat is effectively exchanged across the surface layer, even in the absence of turbulent convection, by means of weak-line and strong-line transmission of radiant energy in both the solar (short-wave-length) and planetary (long-wavelength) domains. The diurnal temperature variation at the top of the boundary layer (~20 m) covers about 75% of that of the surface in opaque dust-laden and about 60% under thin dust conditions. The dust phase diminishes the spectral gappiness inherent in the CO2 absorption bands within the solar and planetary infrared.