NOAA/CMDL KUWAIT AEROSOL DATA FILES The files in this directory contain NOAA/CMDL aerosol data collected onboard the NCAR Electra research aircraft during May and June of 1991 over the Persian Gulf. These data were processed by Dr. Pat Sheridan and Mr. Craig Quincy of NOAA, and are available in graphical form in NOAA Data Report ERL CMDL-10, "Optical Properties of Aerosols in the Kuwait Oil Fire Smoke Plume, May-June 1991". Copies of this Report can be obtained by calling Dr. Sheridan at 303-497-6672. Parameters in these data files were either measured directly or calculated from measurements made with the NOAA multiple-wavelength integrating nephelometer and/or the NOAA aethalometer. Descriptions of these instruments, their operating principles, and any appropriate calibrations or corrections can be found in the NOAA Data Report. Similarly, equations used to calculate various parameters such as Angstrom Exponents and Aerosol Scattering Ratios are documented in the Report. The measurements reported in these files may be regarded as final processed data. Bad or missing data (for example, during an aethalometer filter change or nephelometer clean air check) are flagged by the entry "-999". Two types of data files exist in this directory. These may be broadly classified as Scattering and Absorption data files. The scattering data files contain data derived solely from the nephelometer measurements, and are 1-second ASCII data files. All light scattering measurements relate to scattering by particles, and have been corrected for Rayleigh scatter. The scattering data files have a filename format of SCATNX.ASC, where N is the flight number (1 through 16) and X is the flight segment (A, B, C, etc.). As explained in the NOAA Data Report, no data were recorded during Flight Number 5 (May 25) due to a data system crash. The parameters in these files are listed in columns as described below. Aerosol scattering ratio is the sum of aerosol and Rayleigh scattering coefficients divided by the Rayleigh scattering coefficient. Column Parameter Column Heading Units 1 TIME TIME (UCT) HH:MM:SS 2 Aerosol Light Scattering X449 (M-1) M-1 Coefficient (449 nm) 3 Aerosol Light Scattering X536 (M-1) M-1 Coefficient (536 nm) 4 Aerosol Light Scattering X690 (M-1) M-1 Coefficient (690 nm) 5 Angstrom Exponent (Wavelengths 1-2) ALPHA12 none 6 Angstrom Exponent (Wavelengths 2-3) ALPHA23 none 7 Aerosol Scattering Ratio (449 nm) SR449 none 8 Aerosol Scattering Ratio (536 nm) SR536 none 9 Aerosol Scattering Ratio (690 nm) SR690 none The absorption data files contain data that are related to aethalometer light absorption measurements. The aethalometer was operated with an integration time of 10 seconds, so the absorption data are listed as 10-second ASCII data. The absorption data files have a filename format of FNABS.ASC, where N is the flight number (3 through 14). As explained in the NOAA Data Report, NOAA personnel were not onboard the aircraft during Flight Numbers 1, 15, and 16, and no absorption measurements were made during these flights. The absorption files for Flight Number 2 were corrupted, and we have had no success retrieving these data. The parameters in these files are listed in columns as described below. The aetholometer functions over a broadband visible spectrum. Column Parameter Column Heading Units 1 TIME TIME (UCT) HH:MM:SS 2 Ambient Concentration of Aerosol AMB[BC] ug/m3 Black Carbon 3 Aerosol Light Absorption Coefficient SIGMA AP (M-1) M-1 4 Aerosol Light Extinction Coefficient SIGMA EXT (M-1) M-1 5 Single Scatter Albedo OMEGA none Persons discovering errors in the data files are requested to contact Pat Sheridan at NOAA/CMDL.