SOS99NASH_WP3D_JVAL read me file

//************************************************** 

Principal Investigator and Contact Information:
Rick Shetter
National Center for Atmospheric Research
Mail: P.O. Box 3000, Boulder, CO 80307-3000
Email: shetter@ucar.edu
Phone: 303-497-1480

//**************************************************

NCAR/ARIM
Scanning Actinic Flux Spectroradiometer (SAFS)
SOS Nashville, 6/99 - 7/99
NOAA P3

The data in this directory is only for use by members of the SOS99 field campaign.  The data is subject to change without notice.  Please do not distribute, discuss or make use of any of the data without prior consent from the NCAR SAFS investigators.

o The quantities reported in this file are the total photolysis frequencies (or photolysis rate coefficients, or J-values) of 12 photolysis reactions, calculated by combining direct measurements of the total solar actinic flux with tabulated data for the molecular absorption cross section and dissociation quantum yield of each reaction.

o The instruments used to measure the total solar actinic flux are the NCAR Scanning Actinic Flux Spectroradiometers (SAFS) (Shetter and Muller, JGR, 104,5647-5661,1999).

o The time reported for each record is the recording time of the first non-dark current of each scan (precisely, the 292 nm wavelength). The individual reactions have different  sampling intervals and different midpoints around which these intervals are centered.

o All data points taken are included, i.e. no outlier screening or smoothing has been applied  to these data.

o A preliminary estimate of the instrumental uncertainty of the spectroradiometer technique  is approximately 10% (dependent on spectral range and molecular data).

o A list of Quantum Yield and Cross Section data used in the computation of each  Photolysis Reaction follows. Also listed is the lower limit of detection (L_LOD) for each reaction: if the computed j-value of a reaction is less than the corresponding L_LOD, the value is set to L_LOD.

     PHOTOLYSIS REACTION            XSxQY                              L_LOD (1/sec)
  - J[O3 -> O2 + O(1D)]             (xs:WMO85+Molina/qy:Talukdar98)    3.0E-08
  - J[NO2 -> NO + O(3P)]            (xs:JPL94/qy:Gardiner)             1.0E-07
  - J[H2O2 -> 2 OH]                 (xs:JPL97/qy:1)                    6.0E-10
  - J[HNO2 -> OH + NO]              (xs:JPL97/qy:1)                    3.0E-08
  - J[HNO3 -> OH + NO2]             (xs:Burkholder93/qy:1)             2.0E-10
  - J[CH2O -> H + HCO]              (xs:NCAR/qy:Madronich91)           2.0E-09
  - J[CH2O -> H2 + CO]              (xs:NCAR/qy:Madronich91)           2.0E-09
  - J[CH3COCH3]                     (xs:Martinez91/qy:McKeen97)        7.0E-10
  - J[CH3OOH -> CH3O + OH]          (xs:IUPAC97/qy:1)                  4.0E-10
  - J[CH3ONO2 -> CH3O+NO2]          (xs:Talukdar97/qy:1)               3.0E-10
  - J[PAN + hv -> products]         (xs:Talukdar95/qy:1)               2.0E-10
  - J[CH3CH2ONO2 + hv -> Products]  (xs:Talukdar97/qy:1)               4.0E-10

o USE OF THIS DATA REQUIRES PERMISSION FROM THE PIs.

o For any questions please contact the Principal Investigator Rick Shetter (shetter@ucar.edu) or the ARIM data manager Luca Cinquini (luca@ucar.edu).

//**************************************************