Replicating the Aerosol

Abstract

Replication is a common practice in scientific research on atmospheric aerosols, reproducing some physical aspect of actual aerosols in their technical replicates. From experimental studies on replicates, we may improve our understanding of the poorly constrained effect of aerosols on climate. But for a variety of reasons, the replicate – whether a bulk liquid or model parametrization – can never be an atmospheric aerosol. This dissertation considers the undeniable contingency to any aerosol replication, which only makes legitimate replicates from a set of conditions that do not apply all the time. Despite its fundamental role in justifying the practice of replication, contingency is sometimes forgotten, stretched beyond the limits of its assumptions, or otherwise breached in scientific research. Using brown carbon and stratospheric volcanic sulfate as case studies, this thesis builds a case for recognizing contingency by addressing some of the perils that are risked when contingency is ignored in the replication of aerosols. At stake is the way we understand aerosol effects on climate and its surrounding politics.