Reply on RC1

Abstract

Fire emissions influence radiation, climate, and ecosystems through aerosol radiative effects. Meanwhile, these environmental perturbations can feed back to affect fire emissions. However, the magnitude of such fire-climate interactions remains unclear on the global scale. Here, we quantify the impacts of fire aerosols on climate through direct, indirect, and albedo effects based on the two-way simulations using a well-established chemistry-climate-vegetation model. Globally, fire emissions cause a reduction of -0.57 W m-2 in net radiation at the top of atmosphere with dominant contributions by aerosol indirect effect (AIE). Consequently, surface air temperature decreases by 0.06 °C with coolings of > 0.25 °C over eastern Amazon, western U.S., and boreal Asia. Both aerosol direct effect (ADE) and AIE contribute to such cooling while the aerosol albedo effect (AAE) exerts an offset warming especially at high latitudes. Land precipitation decreases by 0.018 mm month-1 mainly due to the inhibition in central Africa by AIE. Such rainfall deficit further reduces regional leaf area index (LAI) and lightning ignitions, leading to changes in fire emissions. Globally, fire emissions reduce by 2 %–3 % because of the fire-induced changes in humidity, lightning, and LAI. The fire-climate interactions may cause larger perturbations to climate systems with likely more fires under global warming.