Bubble grain growth in ice: experiments and simulation

Hailstones in the clouds develop under various environmental conditions (temperature, humidity, wind, etc.), which impact the size and texture of the ice composing the hail. The stratified structures within a hailstone provide direct insight into the stages it underwent during its growth. In each region, the grains grow with numerous bubbles both inside them and along the grain boundaries (GBs). As hail takes shape, its grain size gradually increases while within the storm cloud and this growth continues even after it falls to the ground. Grain growth is a thermally activated process that modifies the structure of hail, influenced by the presence of bubbles and atmospheric contaminants accumulated within the cloud. This study examines the evolution of grain size in a cylindrical hailstone containing bubbles, employing theoretical equations and a Monte Carlo-based growth model. The computational results contribute to a better understanding of the interaction between GBs and pre-existing bubbles, thereby elucidating the grain size evolution in hailstone containing bubbles near the melting point. Additionally, the study assesses the significance of bubbles in retaining information about a storm within hailstones.