The overarching goal of the SABRE mission is to significantly advance our understanding of the present day composition, chemistry, and dynamics of the stratosphere and their impacts on the climate system. SABRE measurements will greatly enhance the stratospheric observational database of the chemical, dynamical and microphysical processes that determine the formation, evolution and transport of stratospheric aerosols and their radiative properties. We seek to characterize the baseline state and variability of the stratosphere and its role in the radiative budget that determines Earth's climate.
The detailed SABRE in situ measurements are critical for
SABRE measurements will ultimately enable more accurate quantification of the direct and indirect climate impacts from variations in stratospheric aerosols in the present-day atmosphere and provide a foundation for estimating changes in aerosol radiative forcing under future climate scenarios.
Specific SABRE science objectives are:
Individual SABRE deployments are planned to investigate in detail the various chemical and dynamical processes that influence stratospheric aerosol loading. Since tropical and monsoon regions with frequent intense deep convection represent major transport pathways for aerosol and aerosol precursors to enter the stratosphere, measurements at low latitudes will be needed to constrain the sources and processes contributing to the background stratospheric aerosol. Latitudinal transects and measurements at high latitudes will investigate stratospheric transport processes and permit an assessment of the overall stratospheric sulfur budget. Recent studies have shown that frequent moderate volcanic eruptions as well as pyrogenic injections can contribute significantly to stratospheric aerosol loading. The mature SABRE payload will allow rapid deployments in response to these events, providing a comprehensive suite of measurements for studying the chemical and physical processes following these injections. The SABRE sampling strategy is designed to address both questions related to stratospheric aerosol budgets and properties as well as the overall life cycle of stratospheric aerosol.
The detailed in situ measurements will also be used to improve satellite retrievals of stratospheric aerosol properties, and the combined satellite retrievals and in situ measurements will be used to evaluate and improve aerosol representations in global models, ultimately resulting in improved forecasts of future changes in stratospheric aerosols and their impacts on the radiation budget and climate.