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Abstract
Observations indicate spiral galaxies ubiquitously launch multiphase outflows, which help to explain observations of self-regulating star formation in the disk and metallicities of the circumgalactic, intergalactic, and intracluster media much higher than primordial abundances. These outflows are composed of hot $10^{6-7}$,K X-ray emitting gas, cool atomic $sim10^4$,K gas, cold molecular gas, and cosmic rays. The observed rapidly outflowing cool and cold gas phases are theoretically puzzling, as such gas should be incorporated into the hot phase before it can be entrained. The presence of cold gas in the ram pressure stripped tails of galaxies in cluster outskirts is similarly surprising, as the intracluster medium is even hotter $sim$10$^8$,K. In this dissertation, I study the physics responsible for launching galactic outflows at multiple scales. Performing simulations on the scale of interstellar medium patches, I find that cosmic-ray transport plays a crucial role in their ability to launch outflows. Temperature-dependent transport of cosmic rays helps launch fast outflows and generate large-scale radio halos. Studying the microscopic scale of individual cold clouds in a thermally driven, transonic outflow, I find molecular material can survive the entrainment process for clouds larger than a critical radius. At the macroscopic scale of global spiral disks in cluster environments, I find cosmic rays modify the response of the interstellar medium to the ram pressure of the intracluster medium wind. Specifically, I find that cosmic rays protect cold, tenuous gas that is otherwise stripped in purely thermal models. Moreover, the influence of cosmic rays on the star formation rate and the accretion of material towards the galactic center, powering the activity of galactic nuclei, may provide new constraints on cosmic-ray transport and calorimetry. These results imply that thermal and cosmic-ray feedback play a crucial role in understanding multiphase galactic outflows.
