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23-March-2007
PLEASE NOTE: These data are subject to
revision and, thus, are password protected. If you wish to have the
data please contact Jim
Johnson or Timothy Bates
for a password.
The first two data sets include particle number-size
distributions in the diameter range of 0.020 to 0.8 micrometers
Stokes diameter made with an "Aitken" DMPS (20 to 200 nm)
and an "Accumulation" DMPS (200 to 800nm). All
measurements were made at a relative humidity of 60%. The
distributions have been cleaned of all data from times of instrument
malfunction or calibration. Additionally, the data set with “filter”
in the name contains only those distributions where the total CN
concentrations were stable over the course of each measurement have
been included.
files: TEXAQS2006_nsd_dmps_vX.csv
TEXAQS2006_nsd_dmps_filter_vX.csv
The second two data sets include
particle number-size distributions in the diameter range of 0.96 to
10 micrometers aerodynamic 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. All measurements were made at a
relative humidity of 60%. The APS data have been cleaned exactly
like the DMPS files described above.
file:
TEXAQS2006_nsd_aps_vX.csv TEXAQS2006_nsd_aps_filter_vX.csv
The third two data sets include particle number-size
distributions in the diameter range of 0.020 to 10 micrometers
Stokes diameter. The distributions are a combination of DMPS and APS
data where the APS data have been converted to Stokes diameters.
This conversion was done 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 measurements were made at
a relative humidity of 60%.
file: TEXAQS2006_nsd_dmps_aps_vX.csv
TEXAQS2006_nsd_dmps_aps_filter_vX.csv
The fourth two data sets include particle number-size
distributions in the diameter range of 0.020 to 10 micrometers
Stokes diameter as described in the previous section that have been
shifted to ambient temperatures and humidities. The growth factors
were calculated from measured chemistry with the same model used for
calculating the densities. The distributions were shifted and then
regridded onto a common set of diameters as described above.
file:
TEXAQS2006_nsd_dmps_aps_ambient_vX.csv
TEXAQS2006_nsd_dmps_aps_ambient_filter_vX.csv
The fifth two data sets include particle mass-size
distributions in the diameter range of 0.020 to 10 micrometers
Stokes diameter, calculated from the number-size distributions
described in the section 3 above. The conversion of number to mass
was done using densities calculated from measured chemistry.
(download only – not available for plotting)
file:
TEXAQS2006_msd_dmps_aps_vX.csv TEXAQS2006_msd_dmps_aps_filter_vX.csv
The sixth two data sets include particle mass-size
distributions in the diameter range of 0.020 to 10 micrometers
Stokes diameter at ambient temperature and RH, calculated from the
number-size distributions described in the section 4 above. The
conversion of number to mass was done using densities calculated
from measured chemistry. (download only – not available for
plotting)
file: TEXAQS2006_msd_dmps_aps_ambient_vX.csv
TEXAQS2006_msd_dmps_aps_ambient_filter_vX.csv
keyword |
description |
---|---|
nsd |
number size distribution |
msd |
mass size distribution |
ambient |
at ambient temperature and RH |
filter |
cleaned of periods where the CN concentrations were not stable |
Table 1: Filename keywords
More information about these data can be found by clicking on the blue "Instrument Information" tab above.
The following files are available for downloading. Please note: one data file may cover more than one time period, thus,some files may be listed more than once. All files are in csv (comma separated value) format. After several lines of general information each file starts with a first row that contains the particle diameter in microns for that column. The first column contains the date/time in Day-of-Year, DOY. DOY 32.5 is 1200 noon UTC on 1-February. All data are in units of dN/dlog10(Dp), N/cm^3. Missing data are designated by a -99 or a -999.
Start Date | End Date | ASCII file |
---|---|---|
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_filter_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_aps_v0.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_aps_filter_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_aps_v0.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_aps_filter_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_aps_ambient_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_nsd_dmps_aps_ambient_filter_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_msd_dmps_aps_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_msd_dmps_aps_filter_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_msd_dmps_aps_ambient_v1.csv |
27-Jul-2006 | 12-Sep-2006 | TEXAQS2006_msd_dmps_aps_ambient_filter_v1.csv |
U.S.Dept of Commerce / NOAA / OAR / PMEL / Atmospheric Chemistry