Integrating anthropogenic heat flux with global climate models

Nearly all energy used for human purposes is dissipated as heat within Earth's land–atmosphere system. Thermal energy released from non‐renewable sources is therefore a climate forcing term. Averaged globally, this forcing is only +0.028 W m −2 , but over the continental United States and western Europe, it is +0.39 and +0.68 W m −2 , respectively. Here, present and future global inventories of anthropogenic heat flux (AHF) are developed, and parameterizations derived for seasonal and diurnal flux cycles. Equilibrium climate experiments show statistically‐significant continental‐scale surface warming (0.4–0.9°C) produced by one 2100 AHF scenario, but not by current or 2040 estimates. However, significant increases in annual‐mean temperature and planetary boundary layer (PBL) height occur over gridcells where present‐day AHF exceeds 3.0 W m −2 . PBL expansion leads to a slight, but significant increase in atmospheric residence time of aerosols emitted from large‐AHF regions. Hence, AHF may influence regional climate projections and contemporary chemistry‐climate studies.