Effective ice particle densities for cold anvil cirrus

Abstract

This study derives effective ice particle densities (ρe) from data collected by the NASA WB‐57F aircraft near the tops of Florida anvils during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers (CRYSTAL) Florida Area Cirrus Experiment (FACE). The ρe‐ice particle mass divided by the volume of an equivalent diameter liquid sphere‐, is obtained for particle populations () and single sizes from a few to 200–300 μm in maximum dimension using measurements of condensed water content and particle size distributions. Density values are needed for numerical modeling of ice cloud microphysical properties and remote sensing retrievals, and have not up to now been characterized for cold ice clouds containing mixed particle habits. The decrease with increasing slopes of gamma size distributions fitted to the size distributions, ranging from 0.15–0.91 g cm−3. For single sizes, ρe obeys a power‐law with an exponent of about −0.4.