This dataset contains comprehensive measurements of aerosol microphysical, chemical, and optical properties derived for both dry and ambient conditions from in situ measurements made during the four ATom campaigns. The dataset includes composition-resolved size distributions the integrated mass of sulfate, organics, nitrate, sea salt, dust, black carbon, and other compounds in coarse and fine fractions; extinction and absorption coefficients from each species at both dry and ambient conditions; asymmetry parameters; Angstrom exponents; and fitted lognormal functions to describe the size distribution. Optical parameters are calculated for 10 wavelengths from the near UV to the near IR, and size distributions range from 3 nm to 50 um in diameter. One file contains these data at 1-minute time intervals. Another file contains a subset of these data averaged into 1-km vertical bins for each vertical profile the aircraft made, as well as composition-resolved integrated aerosol optical depth derived from each profile. The concentration of cloud condensation nuclei is calculated for 5 supersaturations.

This dataset provides the number, surface area, and volume concentrations and size distributions of dry aerosol particles measured by the Aerosol Microphysical Properties (AMP) instrument package during airborne campaigns conducted by NASA's Atmospheric Tomography (ATom) mission. Five instruments--two nucleation-mode aerosol size spectrometers (NMASS), two ultra-high sensitivity aerosol spectrometers (UHSAS), and a laser aerosol spectrometer (LAS)--comprise the AMP package. The AMP payload provides size distributions with up to one-second time resolution for dry aerosol particles between 0.003 and 4.8 microns in diameter.

This dataset provides the number, surface area, and volume concentrations and size distributions of dry aerosol particles measured by the Aerosol Microphysical Properties (AMP) instrument package during airborne campaigns conducted by NASA's Atmospheric Tomography (ATom) mission. Five instruments--two nucleation-mode aerosol size spectrometers (NMASS), two ultra-high sensitivity aerosol spectrometers (UHSAS), and a laser aerosol spectrometer (LAS)--comprise the AMP package. The AMP payload provides size distributions with up to one-second time resolution for dry aerosol particles between 0.003 and 4.8 microns in diameter.

This dataset consists of (a) selected aerosol and gas-phase observations made on all four deployments of NASA Atmospheric Tomography Mission (ATom), (b) thermodynamic properties related to aerosol formation derived from these measurements, (c) 48-h back trajectories for ATom-4 observations, and (d) output from the Model of Aerosols and Ions in the Atmosphere (MAIA). ATom observations, thermodynamics, and back trajectories were inputs for MAIA model runs. MAIA runs focused on data from ATom-4 deployment, and output includes aerosol formation rates, and ultrafine particle size distributions and number concentrations in the lowermost stratosphere (LMS). ATom 1-4 deployments included all four seasons from 2016 to 2018. This investigation sought to understand how new particle formation (NPF) can occur in the LMS, factors influencing the amount of NPF, and other potential sources of ultrafine aerosols in this region of the atmosphere. The data are provided in comma-separated value (CSV) format.

This dataset provides (1) the results of in situ aerosol particle property measurements collected over remote tropical areas of both Pacific and Atlantic Oceans during the NASA airborne Atmospheric Tomography (ATom) campaigns for ATom-1 and ATom-2 and (2) modeled outputs of comparable aerosol properties, atmospheric chemistry and meteorology at 70 m resolution from four chemical-transport models matched to the location and time of the aircraft measurements.

This dataset provides information on greenhouse gases and human-produced air pollution, including atmospheric concentrations of carbon dioxide (CO2), methane (CH4), tropospheric ozone (O3), and black carbon (BC) aerosols, collected during airborne campaigns conducted by NASA's Atmospheric Tomography (ATom) mission. This dataset includes merged data from all instruments plus additional data such as numbered profiles and distance flown. Merged data products have been created for seven different aggregation intervals (1 second, 10 seconds, and 5 instrument-specific intervals). In the case of data obtained over longer time intervals (e.g., flask data), the merge files provide (weighted) averages to match the sampling intervals. This comprehensive dataset will be used to improve the representation of chemically reactive gases and short-lived climate forcers in global models of atmospheric chemistry and climate.

This dataset provides the atmospheric concentrations of separated ions from inorganic and organic species measured by the High-Resolution Aerosol Mass Spectrometer (HR-AMS) collected during flights of the NASA ATom Mission. Data are available from all four ATom Campaigns. The HR-AMS detects non-refractory submicron aerosol composition by impaction on a vaporizer at 600 degrees C, followed by electron ionization and time-of-flight mass spectral analysis. The measurements include chemically speciated submicron non-refractory particulate mass at a one second and 60 second resolution, and the size distribution of chemically speciated submicron non-refractory particulate mass at 60 second resolution.

This dataset consists of (a) selected aerosol and gas-phase observations made on all four deployments of NASA Atmospheric Tomography Mission (ATom), (b) thermodynamic properties related to aerosol formation derived from these measurements, (c) 48-h back trajectories for ATom-4 observations, and (d) output from the Model of Aerosols and Ions in the Atmosphere (MAIA). ATom observations, thermodynamics, and back trajectories were inputs for MAIA model runs. MAIA runs focused on data from ATom-4 deployment, and output includes aerosol formation rates, and ultrafine particle size distributions and number concentrations in the lowermost stratosphere (LMS). ATom 1-4 deployments included all four seasons from 2016 to 2018. This investigation sought to understand how new particle formation (NPF) can occur in the LMS, factors influencing the amount of NPF, and other potential sources of ultrafine aerosols in this region of the atmosphere. The data are provided in comma-separated value (CSV) format.

This dataset provides (1) the results of in situ aerosol particle property measurements collected over remote tropical areas of both Pacific and Atlantic Oceans during the NASA airborne Atmospheric Tomography (ATom) campaigns for ATom-1 and ATom-2 and (2) modeled outputs of comparable aerosol properties, atmospheric chemistry and meteorology at 70 m resolution from four chemical-transport models matched to the location and time of the aircraft measurements.

This dataset contains single-particle aerosol composition as measured by the Particle Analysis by Laser Mass Spectrometry (PALMS) instrument during the four ATom campaigns from 2016-2018. Single aerosol particles are classified into several particle types, including: mixed sulfate/organic nitrate, biomass burning, elemental carbon, mineral/metallic, meteoric material, alkali salt, sea salt, heavy oil combustion, and others. Particle types are reported as raw number fractions and as absolute mass concentrations. PALMS measures aerosol composition for particles from diameter ~100 to 5000 nm, with most of the particle data in the size range ~150 to 3000 nm. Also included are absolute aerosol concentrations measured by a modified Laser Aerosol Spectrometer (LAS). Integrated number, surface area, and volume concentrations from LAS are reported over multiple size ranges.