Relationship between cloud droplet effective radius and cloud top height for deep convective clouds in CloudSat data product

Recent researches suggest that reduced cloud droplet effective radius by aerosol causes clouds to invigorate. The number of researches by observation data is still small and limited to tropical regions. To investigate this hypothesis, relationship between cloud droplet effective radius and cloud top height is examined globally by using CloudSat data product. The results show significant negative correlation between cloud droplet radius and cloud top height. This relationship is found to exist in the 2 m temperature range as low as 0-10 degree Celsius, which indicates that invigoration exists outside of tropical regions. The validity of the hypothesis that extra latent energy released by delayed phase change is also investigated from the aspect of temperature dependence. However, the results showed no dependence on 2 m temperature.