Adiabatic clouds have been assumed in many applications; however, measured microphysics often deviate from the adiabatic state. Previous studies have been largely focused on the sub-adiabaticity due to entrainment-mixing. In contrast, this study identifies and examines the super-adiabatic evaporation affected by entrainment-mixing. By analyzing observations from the Physics of Stratocumulus Top project, we show that 26 out of 32 complete profiles exhibit super-adiabatic evaporation, which is further reproduced and investigated using the Explicit Mixing Parcel Model simulations. The results suggest that droplet evaporation from entrainment-mixing continues during descent rather than terminating at cloud top. The combination of droplet evaporation from entrainment-mixing and adiabatic descent leads to super-adiabatic evaporation during descent. Further analysis reveals that factors both inside and outside the stratocumulus clouds significantly influence super-adiabatic evaporation. Specifically, larger temperature, smaller relative humidity, larger fraction of entrained dry air, larger turbulent dissipation rate and smaller magnitude of vertical velocity can cause stronger super-adiabatic evaporation in both observations and simulations. The results provide new insights into the theoretical understanding of (non-)adiabaticity and highlight the need to modify adiabatic assumption in remote sensing and atmospheric modeling.
 

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