Bridging the gap between applied meteorology and climate science: a white roof example

White roof is a widely studied urban heat mitigation strategy and frequently incorporated into climate adaptation plans by cities. The effects of white roofs on temperature are often studied within the framework of applied meteorology, with most research focusing on quantifying air temperature reductions under various white roof scenarios (e.g., differing study areas, durations, roof albedos, and adoption rates). Here, the white roof problem is reframed to a climate science problem by focusing on the roof surface temperature and incorporating concepts of climate forcing, sensitivity, and feedback. Different from the Albedo Cooling Effectiveness (ACE) index used for quantifying white roof effects, a new index called Albedo Cooling Sensitivity (ACSs, where the subscript 's' indicates surface) is proposed as a stepping stone towards understanding white roof effects. Moreover, a linearized surface energy balance (SEB) model is utilized to interpret the variability of ACSs simulated by the Weather Research and Forecasting (WRF) model. The variability of ACSs across space and across different model runs with different boundary layer schemes is found to be strongly related to the variability of convective heat transfer efficiency. It is recommended that climate forcing, sensitivity, and feedback be systematically integrated into the analysis of diverse urban adaptation strategies.