Enhancing urban climate-energy modeling in the Community Earth System Model (CESM) through explicit representation of urban air-conditioning adoption

Despite recent improvements to its fully coupled Building Energy Model (BEM), the current Community Land Model Urban (CLMU) in the Community Earth System Model (CESM) lacks the infrastructure to model air-conditioning (AC) adoption explicitly. This undermines CESM's fidelity in modeling urban climate and energy use, and limits its use in climate and energy risk assessments.

Here, we establish a new parameterization scheme in CESM that represents AC adoption explicitly through an AC adoption rate parameter in the BEM of CLMU, and build a present-day, global, survey-based, and spatially explicit AC adoption rate data set at country and sub-country level that is integrated within CESM. The new data set can be leveraged for other ESMs or global-scale models and analyses. The explicit AC adoption scheme and the AC adoption rate data set significantly improve the accuracy of anthropogenic heat modeling due to AC in CESM.