research
Aerosol-Cloud Interactions
Not all clouds respond to changes in aerosol loadings in the same way. I study which clouds are most susceptible to aerosol-induced changes, by using new cloud identification and tracking tools to separate different cloud modes. I also investigate how aerosol-cloud interactions impact the convective transport of aerosols. The latest paper I led on this showed that in more polluted environments, clouds are actually less able to regulate the aerosol loadings by rainout, so more aerosol is transported into the free troposphere.
Mesoscale Heterogeneity
In the real world, aerosol emissions can be localized on mesoscales (i.e., on the order of 100km). The differing aerosol radiative effects between regions of high and low aerosol loading drives changes to the overall circulation. We've used idealized models and satellite case studies to study this phenomenon, which we call the "aerosol breeze". Read more about aerosol breezes in this paper, where we also discuss how important it is to represent mesoscale aerosol gradients in GCMs to accurately assess aerosol-cloud interactions.
Aerosols, Land Cover, and Clouds
Humans are driving changes in the aerosol environment and in land cover. These changes are usually studied separately, but understanding their interactions is important to fully assessing how clouds and precipitation might change in future worlds. My Ph.D. dissertation is funded by a NASA FINESST award that looks at land-aerosol-cloud interactions. I'm currently working on a satellite-based study of how deforestation in Southeast Asia drives changes in clouds. One important point is that we find the impact of deforestation is not uniform everywhere––the environmental humidity and aerosol loading can be important modulators of these land-atmosphere interactions.