tdmadap: Aerosol Properties derived from TDMA Measurements
General Data DescriptionThe Tandem Differential Mobility Analyzer (TDMA) is an instrument to measure dry size distribution and the size resolved hygroscopic growth factors. In its standard operating mode, the dry aerosols are separated into size bins by the first DMA, then exposed to 85% relative humidity and the resulting hygroscopic growth factor distributions for each dry size bin scanned by the second DMA. The aerosol properties described here are derived from the TDMA data by value added procedures created and run by Don Collins at Texas A & M University.
Expected cumulative CCN concentration as a function of supersaturation based on measured size and hygroscopicity distribution, 1/cm^3
Expected differential CCN concentration as a function of supersaturation based on measured size and hygroscopicity distribution, 1/cm^3
Texas A & M provides their own auxiliary QC values, as follows:
- 0 indicates no flag
- 1 indicates that the distribution is somewhat unusual and may be inaccurate. These distributions are used in the calculated products available in other datastreams.
- 2 indicates that the distribution is highly unusual and is likely inaccurate. These distributions are not used in the calculated products available in other datastreams.
Temporal CoverageData are available from
- 2005-10-07 through 2007-12-26 and
- 2009-01-01 through 2009-05-31.
The data are processed periodically at Texas A&M and will eventually be available for the entire period of the TDMA deployment.
Area CoveredData are collected at the SGP Central Facility site, in Oklahoma.
Data Stream InputssgptdmaccncollX1.00 consisting of two files:
To determine the CCN AQC values, the AQC values from the corresponding size
distribution and hygroscopic netCDF files are read:
Notification Form LinkNotification Form
Related LinksDon Collins' group at Texas A&M
Texas A & M, Department of Atmospheric Science, Aerosol Research Group
TranslatorPacific Northwest National Laboratory
Brookhaven National Laboratory
externalTexas A&M University
InstitutionDon Collins' group at Texas A & M, Department of Atmospheric Science, Aerosol Research Group
TDMA - Tandem Differential Mobility Analyzer ACRF - ARM Climate Research Facility CCN - Cloud Condensation Nuclei