By considering the aircraft observational data of the stratocumulus obtained during the Routine AAF (Atmospheric Radiation Measurement(ARM) Aerial Facility) Clouds with Low Optical Water Depths(CLOWD) Optical Radiative Observations(RACORO) field operation that was accomplished in April and May 2009,two approaches were adopted in order to estimate the aerosol incidental effects.The first effect was estimated by considering the cloud drop concentration(AIE_n),while the second effect was estimated by considering the effective radius(AIE_s).It was observed that the AIE_n always owned the higher value in comparison with AIE_s,and this alteration was more projecting especially at moderate liquid water content.Theoretical derivation established on the base of deviation between AIE_n and AIE_s indicated that the dispersion of cloud droplet spectrum influentially related to the effect of aerosol in the consideration of the dispersion effect.It was observed that when the dispersion effect increased the value of evaluated AIE_n come closer to the evaluated value of AIE_s,and the happening of this corresponds authenticated the theoretical expectations.The contribution of the dispersion effect in the consideration of the aerosol indirect effect was the leading offset effect,which owned the largest value at moderate liquid water content,and it was observed that when liquid water content is 0.24 g/m³ then its corresponding percentage was about 37%.The consequences of this research enhance the theoretical understanding of the aerosol-cloud interaction and it can be concluded that it could be helpful asset to improve the accurate assessment of the aerosol indirect effect in models and observations.