Watching super-cooled water droplets nucleate heterogeneously with high speed cryo-microscopy

With the increase of wildfires, there is a surge of organic aerosols present in the atmosphere. Recent evidence from our group and the community suggests that organic matter within droplets can catalyze heterogeneous ice nucleation. We developed a method to visualize in real-time freezing from organic aerosols using a high speed cryo-microscopy set up. We’re learning that hydrophobic interfaces are key to predicting the onset of freezing, and propose parameterizations based on physicochemical properties and mechanisms rather than empirical experimental data.