HALO is based in Cairns, Australia for the CAFE-Pacific campaign.
The main objective of the CAFE missions is to investigate tropical tropospheric oxidant photochemistry in combination with aerosol particle formation and growth under clean, pristine conditions over land, and contrast the results with those in marine and polluted conditions. The measurements constrain computer models that represent chemical processes, environmental feedback mechanisms up to the Earth system, in order to generalize the results to regional and global scales. The data support studies of the atmospheric oxidation capacity and the abundance of fine particulate matter in relation to clouds, climate and planetary health. The studies of unpolluted, pristine conditions provide a reference for human‐induced perturbations in the Anthropocene, as well as constraints on atmospheric conditions in the Earth’s history.