New airborne research facility observes sensitivity of cumulus cloud microphysical properties to aerosol regime over the great barrier reef†

Abstract

Our work on aerosol–cloud–radiation interactions became hamstrung by the lack of a suitable aerosol and cloud microphysics equipped aircraft in Australia. To address this infrastructure gap, we have established a new airborne research platform, designed primarily for Marine Cloud Brightening (MCB) field studies but with broader applicability across diverse airborne research domains. This platform, comprising a Cessna 337 aircraft was outfitted with a comprehensive suite of meteorological, aerosol, and cloud microphysical instrumentation normally only found on much larger aircrafts. The aircraft has completed its first field deployment over the Great Barrier Reef (GBR) supporting the Reef Restoration and Adaptation Program. Here we present details of the platform configuration, a flight summary of its first campaign and a case study illustrating the capabilities of the new platform. In the case study presented, data was collected from two well-developed cumulus cloud cells which were similar in macrophysical properties but formed under markedly different aerosol regimes. We observed a strong difference in cloud microphysical properties. Higher aerosol concentrations led to more numerous and smaller cloud drops and suppressed warm rain. Our observations are consistent with the hypothesis that cumulus clouds, dominant over the GBR during summer, are amenable to marine cloud brightening. Our results demonstrate the practical utility of the new research aircraft through a focused case study, laying the groundwork for future scientific investigations of aerosol–cloud interactions.