The Role of Submicron Aerosol Particles in the Formation of High Ice Water Content Regions

Mesoscale convective systems (MCS) are ubiquitous in tropical latitudes and are responsible for the majority of the precipitation in the tropics (Houze, 1993; Aumann and Ruzmaikin, 2013). Due the deep vertical development in MCS, liquid, mixed-phase and ice clouds are typically present making difficult their characterization. Although ice water content values larger than 1 g m^-3 are often measured in the convective region of MCSs, their mechanism is not well understood. The formation of high ice water concenter (HIWC) regions can affect cloud lifetime and influence precipitation patterns and the radiative balance. HIWC regions also play an important role in aviation safety.

With the aim of improving the HIWC sources and characteristics, eleven research flights were conducted with the Convair-580 around Cayenne (French Guiana) in May 2015. This paper examines the relationship between submicron aerosol particles and formation of HIWC regions. Analysis of vertical aerosol profiles and their correlation with ice water content and cloud droplet number concentrations is presented.

References

- Houze, R. A., Jr. (1993), Cloud Dynamics, 573 pp., Academic, San Diego, California.

- Aumann HH, Ruzmaikin A. (2013), Frequency of deep convective clouds in the tropical zone from 10 years of AIRS data. Atmospheric Chemistry & Physics 13: 10 795–10 806, doi:10.5194/acp-13-10795-2013.