High-resolution, multidimensional solar radiation evaluation for the scientific protection of built heritage sites

Solar radiation heterogeneity across exposed heritage sites drives material deterioration, yet systematic quantification remains elusive due to the absence of operational assessment frameworks. Here, we present a multidisciplinary framework that integrates high-resolution geometric data with multidimensional sky models to quantify solar radiation distribution of large-scale heritage surfaces. Applied to grotto temple sites, we demonstrate that annual cumulative direct solar radiation exhibits substantially greater spatial variability across surface orientations than diffuse radiation. Monthly direct radiation shows marked inter-heritage variations with less predictable patterns compared to diffuse components. Radiation intensity differences between winter and summer solstices are pronounced, with noon-time exposure varying up to threefold across orientations. Critically, solar radiation-driven thermal stress calculations reveal extreme gradients, with protruding surfaces and edges experiencing pressures of 400-500 kPa, while adjacent shaded areas sustain only 50-100 kPa, creating more than fivefold stress differentials. This flexible framework provides site-specific performance metrics to inform the development of advanced conservation materials and targeted intervention strategies for diverse heritage sites.