Automated Continuous-Flow Thermal-Diffusion-Chamber Type Ice Nucleus Counter

Abstract

We built a Continuous-Flow Diffusion-Chamber type Ice Nucleus Counter based on the design of Rogers et al. (1988) at Colorado State University, USA and have improved it to operate automatically. The main improvements are 1) automatic procedures to coat the cylinder walls with ice, 2) automatic measurements of temperature and supersaturation spectra of ice nuclei activation, and 3) reducing the heat inertia of inner cylinder to shorten the time for scanning the activation temperatures and supersaturations.
Its performance is briefly demonstrated through examples of measurements on activation spectra of ice nuclei for summertime atmospheric aerosol particles in the central part of Japan and for test aerosol particles (Arizona Test Dust and ice nucleating bacteria, Snomax®).