SAIL-NET: Investigating Spatial Variability of Aerosol and Cloud Nuclei in Mountainous Terrain

Anna Hodshire, EZRA LEVIN, Gavin McMeeking, Bryan Rainwater, Ethan Emerson, Nicholas Good, Kate Patterson, Tom Ramin, Handix Scientific

     Abstract Number: 176
     Working Group: Remote and Regional Atmospheric Aerosol

Abstract
Atmospheric aerosols can have large impacts on clouds and precipitation by serving as cloud condensation nuclei (CCN) and ice nucleating particles (INP). Understanding the impacts of these particles on clouds is critical to improving our understanding of and ability to forecast precipitation and its resulting impacts on the hydrologic cycle. This predictive ability is especially important in the western United States, and other regions globally, where mountain-impacted precipitation is critical to local and downstream water supplies. To better understand aerosol-cloud interactions in mountain regions, we deploy a novel network of miniaturized instrumentation in the East River Watershed near Crested Butte, Colorado, U.S. in the vicinity of the U.S. Department of Energy (DOE)-funded Surface Atmosphere Integrated Field Laboratory (SAIL). SAIL instrumentation includes an ARM Mobile Facility (AMF2) and the Aerosol Observing System (AOS), which have an extensive suite of aerosol, cloud, and meteorological measurements. These measurements are confined to a limited spatial domain which could miss important regions of aerosol-cloud interactions, especially in complex topography. To expand the SAIL aerosol measurements, we have deployed SAIL-NET, a network of six aerosol measurement nodes spanning both the horizontal and vertical extent of the SAIL domain. Each microphysics measurement node includes a small optical particle counter (POPS) which provides particle number and size between 140 nm - 2 um; a novel, miniature cloud condensation nuclei counter (CloudPuck); and a filter sampler (IcePuck) for subsequent ice nucleating particle analysis. SAIL is scheduled to run between September 2021-June 2023, and SAIL-NET will collect measurements for the majority of that time. We discuss challenges associated with setting up completely self-sufficient remote sites and results on how aerosol concentrations vary both spatially and temporally. Interesting features include remarkably spatially consistent aerosol concentrations in the fall of 2021, with more interesting changes appearing with winter-spring of 2021-2022.