Clouds come in myriad shapes, sizes and types, which control their effects on climate. New research led by the University of Washington shows that splintering of frozen liquid droplets to form ice shards inside Southern Ocean clouds dramatically affects the clouds’ ability to reflect sunlight back to space. The paper, published March 4 in the open-access journal AGU Advances, shows that including this ice-splintering process improves the ability of high-resolution global models to simulate clouds over the Southern Ocean – and thus the models’ ability to simulate Earth’s climate.