ACG_ATOMIC_RHBrown_aerosol_sizedist_aps eng UTF8 dataset service Science Data Integration Group NOAA/PMEL +1 206-526-6744 7600 Sand Point way NE Seattle WA 98115 USA kevin.m.obrien@noaa.gov pointOfContact 2026-03-06 ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) 4 column row vertical temporal PMEL Atmospheric Chemistry ATOMIC Aerosol Size Distribution (APS) data 2026-03-06 creation data.pmel.noaa.gov/pmel ACG_ATOMIC_RHBrown_aerosol_sizedist_aps Coffman, Derek NOAA derek.coffman@noaa.gov https://www.pmel.noaa.gov/acg/data/index.html information web browser Background Information Background information from the source information originator Pacific Marine Environmental Laboratory (PMEL) Size Distributions Aerosol inlet: Ambient aerosol particles were sampled at 18 m above sea level through a heated mast. The mast extended 5 m above and forward of the aerosol measurement container. The inlet was a rotating cone-shaped nozzle that was automatically positioned into the relative wind to maintain nominally isokinetic flow and minimize the loss of supermicrometer particles. Air entered the inlet through a 5 cm diameter hole, passed through a 7 degree expansion cone, and then into the 20 cm inner diameter sampling mast. The flow through the mast was 1 m3 min-1. The transmission efficiency of the inlet for particles with aerodynamic diameters less than 6.5 um (the largest size tested) is greater than 95% [Bates et al., 2002]. The bottom 1.5 m of the mast were heated to establish a stable reference relative humidity (RH) for the sample air controlled to the indicated target sample RH. Twenty one 1.6 cm inner diameter stainless steel tubes extending into the heated portion of the mast were connected to downstream aerosol instrumentation with either conductive silicon tubing or stainless steel tubing for analysis of organic aerosol. DMPS (datasets denoted by _aerosol_sizedist_dmps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to a tandem DMPS system that measured particle size distributions in the range of 0.020 to 0.8 micrometers Stokes diameter. The tandem DMPS consists of an "Aitken" DMPS (0.020 to 0.2 um) and an "Accumulation" DMPS (0.2 to 0.8 um). The distributions have been cleaned of all data from times of instrument malfunction or calibration. APS (datasets denoted by _aerosol_sizedist_aps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to an APS that measured particle size distributions in the range of 0.96 to 10 micrometers Stokes diameter. The APS diameters are aerodynamic and have not been corrected to Stokes diameter via calculation or estimates of particle density. The APS data larger than 10 micrometers are not useful due to significant particle losses in the inlets including the ship's sampling mast, distribution tubing and APS inlet. The distributions have been cleaned of all data from times of instrument malfunction or calibration. Merged (datasets denoted by _aerosol_sizedist): These datasets include particle size distributions in the diameter range of 0.005 to 10 micrometers Stokes diameter. The distributions are a combination of DMPS and APS size distribution data where the APS diameters have been converted to Stokes diameters using densities calculated from measured chemistry. The diameter channels in the overlap region were chosen in the following manner: the last DMPS channel was discarded and, after converting to Stokes diameters, the first APS diameter channel that was larger than the last valid DMPS channel was chosen as the first APS channel. Each combined distribution was regridded onto a common set of diameters. Finally, the regridded distributions were cleaned to eliminate values at the larger sizes from the APS where "phantom" counts resulted in a spurious coarse mode in the surface and volume distributions. All datasets include number size distributions (normalized and non-normalized) as well as the higher moments for each: surface area and volume. Additional datasets may be included for a give project that include: - ambient (_ambient_): includes size distributions shifted to ambient RH using gRH factors - filter (_filter_): includes size distributions where additional cleaning was performed for periods of unstable CN concentrations Coffman, Derek NOAA derek.coffman@noaa.gov https://www.pmel.noaa.gov/acg/data/index.html information web browser Background Information Background information from the source information pointOfContact above aerodynamic aerosol aps area atmosphere atmospheric atomic bin chemistry data datetime diameter distribution dlogDp dNdlogDp dSdlogDp duration dVdlogDp earth environmental identifier laboratory level log log-normal marine mean midpoint noaa normal normalized number pacific particle pmel science sea size station statistics surface trajectory volume width theme Earth Science > Atmosphere > Altitude > Station Height theme GCMD Science Keywords ATOMIC project time latitude longitude altitude theme CF Standard Name Table v70 These data were produced by NOAA and are not subject to copyright protection in the United States. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0-1.0). ATOMIC largerWorkCitation project Unidata Common Data Model Trajectory largerWorkCitation project eng geoscientificInformation 1 -59.6586 -50.925 12.7889 15.8651 seconds 2020-01-07T22:50:00Z 2020-02-11T18:25:00Z 18.0 18.0 PMEL Atmospheric Chemistry ATOMIC Aerosol Size Distribution (APS) data 2026-03-06 creation Coffman, Derek NOAA derek.coffman@noaa.gov https://www.pmel.noaa.gov/acg/data/index.html information web browser Background Information Background information from the source information originator Pacific Marine Environmental Laboratory (PMEL) Size Distributions Aerosol inlet: Ambient aerosol particles were sampled at 18 m above sea level through a heated mast. The mast extended 5 m above and forward of the aerosol measurement container. The inlet was a rotating cone-shaped nozzle that was automatically positioned into the relative wind to maintain nominally isokinetic flow and minimize the loss of supermicrometer particles. Air entered the inlet through a 5 cm diameter hole, passed through a 7 degree expansion cone, and then into the 20 cm inner diameter sampling mast. The flow through the mast was 1 m3 min-1. The transmission efficiency of the inlet for particles with aerodynamic diameters less than 6.5 um (the largest size tested) is greater than 95% [Bates et al., 2002]. The bottom 1.5 m of the mast were heated to establish a stable reference relative humidity (RH) for the sample air controlled to the indicated target sample RH. Twenty one 1.6 cm inner diameter stainless steel tubes extending into the heated portion of the mast were connected to downstream aerosol instrumentation with either conductive silicon tubing or stainless steel tubing for analysis of organic aerosol. DMPS (datasets denoted by _aerosol_sizedist_dmps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to a tandem DMPS system that measured particle size distributions in the range of 0.020 to 0.8 micrometers Stokes diameter. The tandem DMPS consists of an "Aitken" DMPS (0.020 to 0.2 um) and an "Accumulation" DMPS (0.2 to 0.8 um). The distributions have been cleaned of all data from times of instrument malfunction or calibration. APS (datasets denoted by _aerosol_sizedist_aps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to an APS that measured particle size distributions in the range of 0.96 to 10 micrometers Stokes diameter. The APS diameters are aerodynamic and have not been corrected to Stokes diameter via calculation or estimates of particle density. The APS data larger than 10 micrometers are not useful due to significant particle losses in the inlets including the ship's sampling mast, distribution tubing and APS inlet. The distributions have been cleaned of all data from times of instrument malfunction or calibration. Merged (datasets denoted by _aerosol_sizedist): These datasets include particle size distributions in the diameter range of 0.005 to 10 micrometers Stokes diameter. The distributions are a combination of DMPS and APS size distribution data where the APS diameters have been converted to Stokes diameters using densities calculated from measured chemistry. The diameter channels in the overlap region were chosen in the following manner: the last DMPS channel was discarded and, after converting to Stokes diameters, the first APS diameter channel that was larger than the last valid DMPS channel was chosen as the first APS channel. Each combined distribution was regridded onto a common set of diameters. Finally, the regridded distributions were cleaned to eliminate values at the larger sizes from the APS where "phantom" counts resulted in a spurious coarse mode in the surface and volume distributions. All datasets include number size distributions (normalized and non-normalized) as well as the higher moments for each: surface area and volume. Additional datasets may be included for a give project that include: - ambient (_ambient_): includes size distributions shifted to ambient RH using gRH factors - filter (_filter_): includes size distributions where additional cleaning was performed for periods of unstable CN concentrations ERDDAP tabledap 1 -59.6586 -50.925 12.7889 15.8651 seconds 2020-01-07T22:50:00Z 2020-02-11T18:25:00Z 18.0 18.0 tight ERDDAPtabledapDatasetQueryAndAccess https://data.pmel.noaa.gov/pmel/erddap/tabledap/ACG_ATOMIC_RHBrown_aerosol_sizedist_aps ERDDAP:tabledap ERDDAP-tabledap ERDDAP's tabledap service (a flavor of OPeNDAP) for tabular (sequence) data. Add different extensions (e.g., .html, .graph, .das, .dds) to the base URL for different purposes. download PMEL Atmospheric Chemistry ATOMIC Aerosol Size Distribution (APS) data 2026-03-06 creation Coffman, Derek NOAA derek.coffman@noaa.gov https://www.pmel.noaa.gov/acg/data/index.html information web browser Background Information Background information from the source information originator Pacific Marine Environmental Laboratory (PMEL) Size Distributions Aerosol inlet: Ambient aerosol particles were sampled at 18 m above sea level through a heated mast. The mast extended 5 m above and forward of the aerosol measurement container. The inlet was a rotating cone-shaped nozzle that was automatically positioned into the relative wind to maintain nominally isokinetic flow and minimize the loss of supermicrometer particles. Air entered the inlet through a 5 cm diameter hole, passed through a 7 degree expansion cone, and then into the 20 cm inner diameter sampling mast. The flow through the mast was 1 m3 min-1. The transmission efficiency of the inlet for particles with aerodynamic diameters less than 6.5 um (the largest size tested) is greater than 95% [Bates et al., 2002]. The bottom 1.5 m of the mast were heated to establish a stable reference relative humidity (RH) for the sample air controlled to the indicated target sample RH. Twenty one 1.6 cm inner diameter stainless steel tubes extending into the heated portion of the mast were connected to downstream aerosol instrumentation with either conductive silicon tubing or stainless steel tubing for analysis of organic aerosol. DMPS (datasets denoted by _aerosol_sizedist_dmps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to a tandem DMPS system that measured particle size distributions in the range of 0.020 to 0.8 micrometers Stokes diameter. The tandem DMPS consists of an "Aitken" DMPS (0.020 to 0.2 um) and an "Accumulation" DMPS (0.2 to 0.8 um). The distributions have been cleaned of all data from times of instrument malfunction or calibration. APS (datasets denoted by _aerosol_sizedist_aps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to an APS that measured particle size distributions in the range of 0.96 to 10 micrometers Stokes diameter. The APS diameters are aerodynamic and have not been corrected to Stokes diameter via calculation or estimates of particle density. The APS data larger than 10 micrometers are not useful due to significant particle losses in the inlets including the ship's sampling mast, distribution tubing and APS inlet. The distributions have been cleaned of all data from times of instrument malfunction or calibration. Merged (datasets denoted by _aerosol_sizedist): These datasets include particle size distributions in the diameter range of 0.005 to 10 micrometers Stokes diameter. The distributions are a combination of DMPS and APS size distribution data where the APS diameters have been converted to Stokes diameters using densities calculated from measured chemistry. The diameter channels in the overlap region were chosen in the following manner: the last DMPS channel was discarded and, after converting to Stokes diameters, the first APS diameter channel that was larger than the last valid DMPS channel was chosen as the first APS channel. Each combined distribution was regridded onto a common set of diameters. Finally, the regridded distributions were cleaned to eliminate values at the larger sizes from the APS where "phantom" counts resulted in a spurious coarse mode in the surface and volume distributions. All datasets include number size distributions (normalized and non-normalized) as well as the higher moments for each: surface area and volume. Additional datasets may be included for a give project that include: - ambient (_ambient_): includes size distributions shifted to ambient RH using gRH factors - filter (_filter_): includes size distributions where additional cleaning was performed for periods of unstable CN concentrations OPeNDAP 1 -59.6586 -50.925 12.7889 15.8651 seconds 2020-01-07T22:50:00Z 2020-02-11T18:25:00Z 18.0 18.0 tight OPeNDAPDatasetQueryAndAccess https://data.pmel.noaa.gov/pmel/erddap/tabledap/ACG_ATOMIC_RHBrown_aerosol_sizedist_aps OPeNDAP:OPeNDAP OPeNDAP An OPeNDAP service for tabular (sequence) data. Add different extensions (e.g., .html, .das, .dds) to the base URL for different purposes. download PMEL Atmospheric Chemistry ATOMIC Aerosol Size Distribution (APS) data 2026-03-06 creation Coffman, Derek NOAA derek.coffman@noaa.gov https://www.pmel.noaa.gov/acg/data/index.html information web browser Background Information Background information from the source information originator Pacific Marine Environmental Laboratory (PMEL) Size Distributions Aerosol inlet: Ambient aerosol particles were sampled at 18 m above sea level through a heated mast. The mast extended 5 m above and forward of the aerosol measurement container. The inlet was a rotating cone-shaped nozzle that was automatically positioned into the relative wind to maintain nominally isokinetic flow and minimize the loss of supermicrometer particles. Air entered the inlet through a 5 cm diameter hole, passed through a 7 degree expansion cone, and then into the 20 cm inner diameter sampling mast. The flow through the mast was 1 m3 min-1. The transmission efficiency of the inlet for particles with aerodynamic diameters less than 6.5 um (the largest size tested) is greater than 95% [Bates et al., 2002]. The bottom 1.5 m of the mast were heated to establish a stable reference relative humidity (RH) for the sample air controlled to the indicated target sample RH. Twenty one 1.6 cm inner diameter stainless steel tubes extending into the heated portion of the mast were connected to downstream aerosol instrumentation with either conductive silicon tubing or stainless steel tubing for analysis of organic aerosol. DMPS (datasets denoted by _aerosol_sizedist_dmps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to a tandem DMPS system that measured particle size distributions in the range of 0.020 to 0.8 micrometers Stokes diameter. The tandem DMPS consists of an "Aitken" DMPS (0.020 to 0.2 um) and an "Accumulation" DMPS (0.2 to 0.8 um). The distributions have been cleaned of all data from times of instrument malfunction or calibration. APS (datasets denoted by _aerosol_sizedist_aps_): One of the twenty one 1.6 cm diameter tubes was used to supply ambient air to an APS that measured particle size distributions in the range of 0.96 to 10 micrometers Stokes diameter. The APS diameters are aerodynamic and have not been corrected to Stokes diameter via calculation or estimates of particle density. The APS data larger than 10 micrometers are not useful due to significant particle losses in the inlets including the ship's sampling mast, distribution tubing and APS inlet. The distributions have been cleaned of all data from times of instrument malfunction or calibration. Merged (datasets denoted by _aerosol_sizedist): These datasets include particle size distributions in the diameter range of 0.005 to 10 micrometers Stokes diameter. The distributions are a combination of DMPS and APS size distribution data where the APS diameters have been converted to Stokes diameters using densities calculated from measured chemistry. The diameter channels in the overlap region were chosen in the following manner: the last DMPS channel was discarded and, after converting to Stokes diameters, the first APS diameter channel that was larger than the last valid DMPS channel was chosen as the first APS channel. Each combined distribution was regridded onto a common set of diameters. Finally, the regridded distributions were cleaned to eliminate values at the larger sizes from the APS where "phantom" counts resulted in a spurious coarse mode in the surface and volume distributions. All datasets include number size distributions (normalized and non-normalized) as well as the higher moments for each: surface area and volume. Additional datasets may be included for a give project that include: - ambient (_ambient_): includes size distributions shifted to ambient RH using gRH factors - filter (_filter_): includes size distributions where additional cleaning was performed for periods of unstable CN concentrations ERDDAP Subset 1 -59.6586 -50.925 12.7889 15.8651 seconds 2020-01-07T22:50:00Z 2020-02-11T18:25:00Z 18.0 18.0 tight ERDDAP_Subset https://data.pmel.noaa.gov/pmel/erddap/tabledap/ACG_ATOMIC_RHBrown_aerosol_sizedist_aps.subset search Subset Web page to facilitate selecting subsets of the dataset download physicalMeasurement time double Datetime UTC diameter_aero double midpoint Diameter(aerodynamic) trajectory_id String Trajectory ID dNdlogDp double Normalized particle number size distribution (Log-normal) dlogDp double diameter bin width dN double Particle number size distribution dSdlogDp double Normalized particle surface area distribution (Log-normal) dS double Particle surface area size distribution dVdlogDp double Normalized Particle volume distribution (Log-normal) dV double Particle volume size distribution duration int Duration Science Data Integration Group NOAA/PMEL +1 206-526-6744 7600 Sand Point way NE Seattle WA 98115 USA kevin.m.obrien@noaa.gov distributor OPeNDAP DAP/2.0 https://data.pmel.noaa.gov/pmel/erddap/tabledap/ACG_ATOMIC_RHBrown_aerosol_sizedist_aps.html order Data Subset Form ERDDAP's version of the OPeNDAP .html web page for this dataset. Specify a subset of the dataset and download the data via OPeNDAP or in many different file types. download https://data.pmel.noaa.gov/pmel/erddap/tabledap/ACG_ATOMIC_RHBrown_aerosol_sizedist_aps.graph order Make-A-Graph Form ERDDAP's Make-A-Graph .html web page for this dataset. Create an image with a map or graph of a subset of the data. mapDigital This record was created from dataset metadata by ERDDAP Version 2.27.0