IFEG   20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Evaporation process of a cluster of cloud droplets
Autor/es:
N. E. CASTELLANO; E. E. AVILA; G. G. AGUIRRE VARELA
Lugar:
Leipzig
Reunión:
Conferencia; 16th International Conference on Clouds and Precipitation, ICCP-2012.; 2012; 2012
Institución organizadora:
International Commission on Clouds and Precipitation
Resumen:
This study shows that the droplets that form a cluster do not behave as isolated droplets but they interact in such a way that can change the vapor field density and hence the growth or evaporation rates of the droplets. The vapour density value between the droplets increases as the droplet number in the cluster increases. We use a theoretical model based on the electrostatic-image-charge method to calculate the vapor density field for a cloud of monodisperse cloud droplet size distribution immersed in an undersaturated environment. Calculations are performed for variations of droplet size, droplet number, droplet separation, relative humidity and temperature of the environment. It is observed that the external droplets form a screening layer that reduces the effect of the undersaturated environment within the cluster; thus, the droplets located close to the centre of the cluster are screened by the outermost droplets of the cluster. This model allows us to observe that each droplet within the cluster evaporates with a different evaporation rate according to the position that it occupies within the cluster. Droplets near the edge of the cluster are shown to evaporate faster than droplets within the cluster. Besides, the cluster of droplets can substantially influence the vapor density field beyond the region where the cluster is confined. The knowledge of the evolution of the cloud droplet size distribution in the top and edges of clouds is crucial for the determination of their radiative properties, climate modeling and remote sensing.