Aerosol–Cloud–Meteorology Interaction Airborne Field Investigations: Using Lessons Learned from the U.S. West Coast in the Design of ACTIVATE off the U.S. East Coast

Abstract

We report on a multiyear set of airborne field campaigns (2005–16) off the California coast to examine aerosols, clouds, and meteorology, and how lessons learned tie into the upcoming NASA Earth Venture Suborbital (EVS-3) campaign: Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE; 2019–23). The largest uncertainty in estimating global anthropogenic radiative forcing is associated with the interactions of aerosol particles with clouds, which stems from the variability of cloud systems and the multiple feedbacks that affect and hamper efforts to ascribe changes in cloud properties to aerosol perturbations. While past campaigns have been limited in flight hours and the ability to fly in and around clouds, efforts sponsored by the Office of Naval Research have resulted in 113 single aircraft flights (>500 flight hours) in a fixed region with warm marine boundary layer clouds. All flights used nearly the same payload of instruments on a Twin Otter to fly below, in, and above clouds, producing an unprecedented dataset. We provide here i) an overview of statistics of aerosol, cloud, and meteorological conditions encountered in those campaigns and ii) quantification of model-relevant metrics associated with aerosol–cloud interactions leveraging the high data volume and statistics. Based on lessons learned from those flights, we describe the pragmatic innovation in sampling strategy (dual-aircraft approach with combined in situ and remote sensing) that will be used in ACTIVATE to generate a dataset that can advance scientific understanding and improve physical parameterizations for Earth system and weather forecasting models, and for assessing next-generation remote sensing retrieval algorithms.

Atmospheric Research Over the Western North Atlantic Ocean Region and North American East Coast: A Review of Past Work and Challenges Ahead

“…Continued research efforts are critical for a number of reasons. First, improvements in measurement capabilities and models and opportunities for sustained long‐term observations from airborne platforms provide a pathway forward to gain new insights (Sorooshian et al, ). Second, past works reviewed in this paper have raised new questions that warrant investigation.…”

Characterization of Aerosol Hygroscopicity Over the Northeast Pacific Ocean: Impacts on Prediction of CCN and Stratocumulus Cloud Droplet Number Concentrations

“…Earth and Space Science (Coggon et al, 2012(Coggon et al, , 2014Russell et al, 2013;Sorooshian et al, 2019;Wang et al, 2016). The scientific objectives of individual flights included characterization of marine aerosols and clouds, sampling of shipping vessel exhaust plumes, and investigation of nearby wildfire emissions.…”

Aerosols in the E3SM Version 1: New Developments and Their Impacts on Radiative Forcing

“…When light-absorbing aerosols deposit on snow or ice surfaces, they may speed up the melting through the additional absorption of solar radiation (e.g., Flanner et al, 2007;Qian et al, 2011Qian et al, , 2015Warren & Wiscombe, 1980), which has additional important implications for climate change and seasonal distribution of water resource (e.g., Rahimi et al, 2019). The understanding of detailed physical and chemical processes for aerosols and their interactions with other components of the climate system has been obtained from laboratory experiments, field observations, or process modeling studies (e.g., Carslaw et al, 2013;Fanourgakis et al, 2019;Rosenfeld et al, 2014;Shilling et al, 2009;Shrivastava et al, 2015;Sorooshian et al, 2019;Wang et al, 2011). They are very challenging to treat accurately in Earth system models (ESMs) that are relied upon to represent and understand the complex global impact of aerosols and their interactions with the coupled aerosol-cloud-radiation-dynamics system (e.g., Mann et al, 2014;Gettelman, 2015;Zhang et al, 2016;Ghan et al, 2016;Gryspeerdt et al, 2017).…”