The ALICAT Lidar for NASA’s Atmosphere Observing System (AOS) Storm: Implications for Synergistic Diurnal Sampling of Aerosols, Clouds, and Precipitation

The Atmospheric Lidar for Clouds and Aerosol Transport (ALICAT) is a SmallSat elastic backscatter lidar planned to fly in NASA’s AOS-Storm orbit with an anticipated launch in early 2029 with a planned 2-year lifetime. ALICAT will provide vertical measurements of attenuated backscatter and volume depolarization ratio at 532 and 1064 nm for aerosol and cloud profiling coincident with additional AOS-Storm instrumentation, including a Ku-band radar and microwave radiometer, in a 55-degree prescessing orbit, to target diurnal sampling of aerosols, clouds, and precipitation. ALICAT has strong design and algorithm heritage from its predecessor, the Cloud Aerosol Transport System (CATS) technology demonstration that flew on the International Space Station (ISS), but with improvements to enable enhanced dynamic range and solar background rejection for improved SNR compared to Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) that flew on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Additionally, ALICAT we employ recently developed real-time signal denoising and machine learning techniques for improved daytime SNR and feature detection at the native resolution of the raw data. This capability will deliver data products in real-time that can be readily utilized by applications community, particularly for aerosol and weather modeling, health and air quality, and aviation safety. In this presentation, we provide an overview of the ALICAT instrument and heritage, synergy with the AOS-Storm payload, projected performance and comparison to previous spaceborne atmospheric lidar instruments, and recently developed signal denoising and machine learning techniques for improved daytime feature detection.