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ATom: Cloud and Coarse Aerosol Measurements, 2016-2018

Submitted by ORNL DAAC Staff on 2022-04-26
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The CAPS instrument attached to the exterior of the NASA DC-8 aircraft.
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The CAPS instrument attached to the exterior of the NASA DC-8 aircraft.

The ORNL DAAC recently released the following Atmospheric Tomography Mission (ATom) dataset by Weinzierl, B.B., et al. (2021):

ATom: Cloud and Coarse Aerosol Measurements from CAPS Instrument, 2016-2018

This dataset contains cloud type and coarse aerosol contents measured by the University of Vienna's second-generation Cloud Aerosol and Precipitation Spectrometer (CAPS) instrument mounted to the NASA DC-8 aircraft during the four ATom campaigns that occurred from 2016 to 2018. CAPS measures particle size distributions in a size range between nominally 0.5 micrometers and 960 micrometers. Cloud types are determined using an algorithm developed to detect and classify clouds using measurements of CAPS. Relative humidity and temperature are considered by the algorithm. The cloud indicator provides a classification on a 1 Hz basis and separates data in cloud-free, aerosol-cloud transition regime (ACTR), liquid clouds, clouds in the mixed-phase temperature regime (MPTR), and cirrus clouds. The coarse aerosol product provides cloud and aerosol particle number concentrations at standard pressure (1013.25 hPa) and standard temperature (273.15 K) in selected size ranges. Particle sizes refer to ammonium sulfate optical equivalent diameter (m=1.52 + 0.0i).

The Atmospheric Tomography Mission (ATom) is a NASA Earth Venture Suborbital-2 mission to study the impact of human-produced air pollution on greenhouse gases and on chemically reactive gases in the atmosphere. ATom deployed an extensive gas and aerosol payload on the NASA DC-8 aircraft for systematic, global-scale sampling of the atmosphere, profiling continuously from 0.2 to 12 km altitude. Around-the-world flights were conducted in each of four seasons between 2016 and 2018.

Additional data from ATom and other relevant links can be found on the ORNL DAAC's ATom Project Page.

Citation: Weinzierl, B.B., and M. Dollner. 2021. ATom: Cloud and Coarse Aerosol Measurements from CAPS Instrument, 2016-2018. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1981

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