SUCCESS DC-8 1996/04/15-1996/05/15
  ch4: CH4 [ppbv]
  co: CO [ppbv]
  co2: CO2 [ppmv]
  h2o: H2O [g/kg]
  n2o: N2O [ppbv]
  noday:  NO [pptv] SZA<90
  noy: NOy [pptv]
  o3: O3 [ppbv]