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Constituent Observational Database

A very large observational database has been compiled for analysis by the AutoChem assimilation system. It is available for use by others via anonymous ftp. Some of the instruments used are described here.

The directory path gives the instrument, specie, and where relevant the version information (e.g. <platform>/<version>/<species>/). The file name gives the species and date information in the format specie_yyyy_mm_dd.dat.

The data files all have the same format and were written with the following FORTRAN write statement:

WRITE (jout,FMT='(2(1x,i2),1x,i4,1x,i3,1x,11(g13.6,1x),2(g13.6,1x),1x,i6,g13.6)') jday , jmonth , jyear , jdoy , gmt , lat , long , p , t , z , pt , el , elen , data , dataerr , maglat , maglon , isp , sza


  • jday is the day of the month
  • jmonth is the month of the year
  • jyear is the year jdoy is the day of the year
  • gmt is the time, GMT, in hours
  • lat is the latitude in degrees
  • long is the longitude in degrees
  • p is the pressure in mb
  • t is the temperature in kelvin
  • z is the altitude in km
  • pt is the potential temperature in kelvin
  • el is the equivalent pv latitude in degrees
  • elen is the equivalent length of pv
  • data is the v.m.r of the species
  • dataerr is the uncertainty in the v.m.r as a v.m.r
  • maglat is the magnetic latitude in degrees
  • maglon is the magnetic longitude in degrees
  • isp is the sunspot number
  • sza is the solar zenith angle in degrees
Contact the Author | 2006 David Lary