학술논문

Droplet charging in stratiform clouds
Document Type
Working Paper
Source
Subject
Physics - Atmospheric and Oceanic Physics
Physics - Instrumentation and Detectors
Language
Abstract
The role of droplet charge in stratiform clouds is one of the least well understood areas in cloud microphysics and is thought to affect cloud radiative and precipitation processes. Layer clouds cover a large proportion of the Earth's surface and are important in regulating the planetary radiation budget. Using a new remote sensing method developed at our University Observatory, we demonstrate that charge in the base of stratiform clouds is typically of negative polarity, as expected from theory considering the vertical current flow into and out of the cloud. More detailed vertical charge structure of layer clouds can be found using balloon-carried instruments. Our previous research using in situ balloon observations has demonstrated that, on average, the bulk charge polarity and location agrees with theoretical predictions of positive charge at the upper edge and negative charge at the lower edge. Here we present optical and charge measurements of droplets from a variety of stratiform clouds, demonstrating the typical variability which is observed.
Comment: XVI International Conference on Atmospheric Electricity, 17-22 June 2018, Nara city, Nara, Japan