Title: C130 Carbon Dioxide Concentration

Contact:

   Greg Kok
   NCAR-RAF
   Box 3000
   Boulder, Colorado  80307
   phone 303-497-1070
   fax 303-497-1092
   E-Mail Address: kok@ucar.edu


Data Set Description:

     This data set contains carbon dioxide data measured
from the NCAR C-130 on the ACE-1 program.  The CO2
concentration in ppmv is given by the variable, XCOZG.
These data were recorded by the RAF aircraft data system,
and the time will be consistent with that in the general
RAF data set.  Prior to flight 14, there was a leak in one
of the filters and there was considerable shift in the
baseline, giving higher uncertainty in the data.  The
measurements of CO2 were made by a modified LiCor 6262 IR
absorption analyzer.   The instrument is operated in a
differential mode, with a standard cylinder of CO2
continuously flowing through the reference channel.  A
zero measurement was made every 14 minutes by sampling the
same CO2 concentration that was flowing through the
reference channel.  Every 28 minutes in addition to a zero
measurement, two calibration measurements, about 15 ppmv
on either side of the zero concentration were made.
All data during the zero and calibration modes have been
replaced by -32768.  The data has been shifted by 20
seconds to accommodate the sampling lag.  After the
completion of the field measurements the
calibration standards were referenced to
the WMO standard CO2 scale by the NOAA CMDL laboratory
in Boulder, Colorado.

Format: space-delimited ASCII with fields:

Date : (UTC)
YYYY/MM/DD

Time : (UTC)
HH:MM:SS

XLATC :GPS-Corrected Inertial Latitude
deg

XLONC :GPS-Corrected Inertial Longitude
deg

PALT :NACA Pressure Altitude
M

XCOZG :CO Z Acceleration
G


File Name Conventions:
   rfxxx.dat where xxx is the flight number.
   An example for flight 23 is rf23.dat.

References: None.