Multiple Earth system models (ESMs) discretize surface albedo into two semi-broadbands comprising the UV/visible (VIS) and near-infrared (NIR) wavelengths. Here, we use an offline single-column radiative transfer model to investigate the radiative effects of spectrally resolving the surface albedo. We use the Snow, Ice, and Aerosol Radiative model (SNICAR-ADv4), extended to simulate liquid water, to calculate snow, ice, and liquid water albedo. We flux-weight the hyperspectral albedo into the 14 spectral bands used by the atmospheric shortwave radiative transfer model (RRTMG_SW). We establish representative atmospheric profiles for the three surface types and compare their shortwave fluxes and atmospheric warming rates with the 14 band spectrally resolved albedo to those calculated with the semi-broadband approximation. Spectrally-resolved surface albedo over snow and ice reduces atmospheric warming by darkening the albedo of NIR bands, correcting the too-strong surface absorption in visible bands, and too-weak surface absorption in shortwave infrared (SWIR) bands caused by the semi-broadband approximation. We explore the effects on surface and atmospheric warming rates of varying solar zenith angle, cloud cover, relative humidity, and snow grain/air bubble radii. The semi-broadband albedo biases can exceed 10% (4 W/m²) and 2% (2 W/m²) for the surface and atmospheric net flux respectively, being particularly strong under conditions with high atmospheric water-vapor, as water-vapor alters the distribution of insolation.

Furthermore, this semi-broadband albedo bias present in fully coupled ESM’s is compounded by biases in spectral surface insolation, caused by the partitioning of the VIS and NIR bands as they are passed from the atmosphere to the surface components. Correcting this insolation bias shifts 3.5 W/m² flux from the highly absorptive NIR band to the more reflective VIS band, further reducing the surface warming rate by 0.5 W/m² over snow-covered surfaces. These results show that transmitting a higher resolution spectral radiation field between the atmosphere and surface reduces biases in surface absorption and atmospheric heating present in fully coupled ESMs.