Attributes {
 s {
  time {
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.57842e+9, 1.58146559e+9;
    String axis "T";
    String calendar "gregorian";
    Float64 colorBarMaximum 1.582e+9;
    Float64 colorBarMinimum 1.578e+9;
    String ioos_category "Time";
    String long_name "Time";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  trajectory_id {
    String cf_role "trajectory_id";
    String ioos_category "Identifier";
    String long_name "trajectory id";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float64 _FillValue -1.0e+34;
    Float64 actual_range 12.7865, 15.8652;
    String axis "Y";
    Float64 colorBarMaximum 90.0;
    Float64 colorBarMinimum -90.0;
    String comment "In the one minute files the position is treated somewhat differently from all the other data. The position given is the ship's position at the start of the one minute 'averaging' period. All other data are a true average. The PMEL GPS was the primary source. The Ship's GPS was used when there were missing data in the PMEL record";
    String epic_code "500";
    String instrument "GPS";
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
    Float64 valid_max 90.0;
    Float64 valid_min -90.0;
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float64 _FillValue -1.0e+34;
    Float64 actual_range -59.6588, -50.9246;
    String axis "X";
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String comment "In the one minute files the position is treated somewhat differently from all the other data. The position given is the ship's position at the start of the one minute 'averaging' period. All other data are a true average. The PMEL GPS was the primary source. The Ship's GPS was used when there were missing data in the PMEL record";
    String epic_code "502";
    String instrument "GPS";
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  cn {
    Float64 _FillValue -1.0e+34;
    Float64 actual_range 73.4832, 46337.1;
    Float64 colorBarMaximum 100.0;
    Float64 colorBarMinimum 0.0;
    String epic_code "1853";
    String instrument "TSI 3010 (sn: 2470)";
    String ioos_category "Statistics";
    String long_name "Number Concentration of Particles";
    Float64 missing_value -999.0;
    String source "surface observation";
    String standard_name "number_concentration_of_aerosol_particles_at_stp_in_air";
    String units "cm-3";
    Float64 valid_max 50000.0;
    Float64 valid_min 0.0;
  }
  ss {
    Float64 _FillValue -1.0e+34;
    Float64 actual_range 0.06, 0.66;
    Float64 colorBarMaximum 100.0;
    Float64 colorBarMinimum 0.0;
    String epic_code "6201";
    String instrument "DMT CCNC (sn: 0805-0021)";
    String ioos_category "Unknown";
    String long_name "Supersaturation";
    Float64 missing_value -999.0;
    String source "surface observation";
    String units "percent";
    Float64 valid_max 1.6;
    Float64 valid_min 0.0;
  }
  ccn {
    Float64 _FillValue -1.0e+34;
    Float64 actual_range 0.0, 5495.11;
    Float64 colorBarMaximum 100.0;
    Float64 colorBarMinimum 0.0;
    String epic_code "6200";
    String instrument "DMT CCNC (sn: 0805-0021)";
    String ioos_category "Statistics";
    String long_name "Number Concentration of Cloud Condensation Nuclei";
    Float64 missing_value -999.0;
    String source "surface observation";
    String standard_name "number_concentration_of_cloud_condensation_nuclei_at_stp_in_air";
    String units "cm-3";
    Float64 valid_max 50000.0;
    Float64 valid_min 0.0;
  }
  ccn_cn_ratio {
    Float64 _FillValue -1.0e+34;
    Float64 actual_range 0.0, 29.8666;
    Float64 colorBarMaximum 100.0;
    Float64 colorBarMinimum 0.0;
    String epic_code "6202";
    String instrument "DMT CCNC (sn: 0805-0021); TSI 3010 (sn: 2470)";
    String ioos_category "Statistics";
    String long_name "Ratio of CCN to CN";
    Float64 missing_value -999.0;
    String source "surface observation";
    String standard_name "ratio_of_number_concentration_of_cloud_condensation_nuclei_to_number_concentration_of_aerosol_particles_at_stp_in_air";
    String units "1";
    Float64 valid_max 2.0;
    Float64 valid_min 0.0;
  }
 }
  NC_GLOBAL {
    String _NCProperties "version=2,netcdf=4.7.4,hdf5=1.10.6";
    String cdm_data_type "Trajectory";
    String cdm_trajectory_variables "trajectory_id";
    String comment "Unless otherwise noted, 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].\r
\r
The bottom 1.5 m of the mast were heated to establish a stable reference relative humidity (RH) for the sample air of in the controlled range of 55 to 60 %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.\r
\r
A Droplet Measurement Technologies CCN Counter (DMT CCNC) was used to determine CCN concentrations of sub-1 um particles at supersaturations ranging from 0.1 to 0.62%.  A multijet cascade impactor with a 50% aerodynamic cut-off diameter of 1.1 um was upstream of the CCNC. The sampled air was dried prior to reaching the CCNC.  Details concerning the characteristics of the DMT CCN counter can be found in Roberts and Nenes [2005] and Lance et al. [2006]. The CCN counter was calibrated before and during the experiment as outlined by Lance et al. [2006]. The uncertainty associated with the CCN number concentration is estimated to be less than +/- 10% [Roberts and Nenes, 2005]. Uncertainty in the instrumental supersaturation is less than +/- 10% for the operating conditions of this experiment [Roberts and Nenes, 2005].\r
\r
The data are in 10 second time intervals and include CCN concentration (in n/cm^3), CCN/CN ratio, and Supersaturation (in %).\r
\r
Lance, S., J. Medina, J.N. Smith, and A. Nenes, Mapping the operation of the DMT continuous flow CCN counter, Aer. Sci. Tech., 40, 242 - 254, 2006.\r
\r
Roberts, G.C. and A. Nenes, A continuous-flow streamwise thermal gradient CCN chamber for atmospheric measurements, Aer. Sci. Tech., 39, 206 - 221, 2005.";
    String contributor_name "Coffman, Derek;Johnson, James;Quinn, Patricia;Bates, Tim;Upchurch, Lucia";
    String Conventions "CF-1.6, COARDS, ACDD-1.3";
    String creator_email "james.e.johnson@noaa.gov";
    String creator_name "Johnson, James";
    String creator_url "https://saga.pmel.noaa.gov";
    String date_created "2020-11-30T17:19:26Z";
    Float64 Easternmost_Easting -50.9246;
    String featureType "Trajectory";
    Float64 geospatial_lat_max 15.8652;
    Float64 geospatial_lat_min 12.7865;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max -50.9246;
    Float64 geospatial_lon_min -59.6588;
    String geospatial_lon_units "degrees_east";
    String history "file created by NOAA/PMEL/ACG
2024-04-19T00:00:38Z (local files)
2024-04-19T00:00:38Z https://data.pmel.noaa.gov/pmel/erddap/tabledap/EUREC4A_ATOMIC_RonBrown_PMEL_CCN_v2.das";
    String infoUrl "https://saga.pmel.noaa.gov";
    String institution "NOAA PMEL Atmospheric Chemistry";
    String keywords "aerosol, air, atmospheric, atomic, ccn, ccn_cn_ratio, chemistry, cloud, cloud cover, cloudiness, concentration, condensation, cover, data, environmental, identifier, laboratory, latitude, longitude, marine, noaa, nuclei, number, number_concentration_of_aerosol_particles_at_stp_in_air, number_concentration_of_cloud_condensation_nuclei_at_stp_in_air, pacific, particles, pmel, ratio, ratio_of_number_concentration_of_cloud_condensation_nuclei_to_number_concentration_of_aerosol_particles_at_stp_in_air, second, statistics, stp, supersaturation, time, trajectory, trajectory_id";
    String keywords_vocabulary "GCMD Science Keywords";
    String license "The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, ERD, NOAA, nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information.";
    Float64 Northernmost_Northing 15.8652;
    String platform "RHBrown";
    String product_version "2";
    String project "ATOMIC";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing 12.7865;
    String standard_name_vocabulary "CF Standard Name Table v55";
    String subsetVariables "trajectory_id";
    String summary "ATOMIC (Atlantic Tradewind Ocean Atmosphere Mesoscale Interaction Campaign) 2020 Field campaign: Surface meteorological and ship navigation collected from the RV Ronald H. Brown by the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory (PMEL) Atmospheric Chemistry Group in the tropical North Atlantic ocean from 2020-01-09 to 2020-02-13";
    String time_coverage_end "2020-02-11T23:59:50Z";
    String time_coverage_start "2020-01-07T18:00:00Z";
    String title "PMEL Atmospheric Chemistry ATOMIC CCN 10 second data";
    Float64 Westernmost_Easting -59.6588;
    Float64 Westernnmost_Easting -59.6588;
  }
}