ACSOE campaigns:

OXICOA: Sep 9-19, 1996
TACIA: Apr 2 -10, 1997
NARE: Aug 11 - Sep 23, 1997
ACE-2: (see ACE-2)

Brief description

Special remarks concerning ETHmeg database content

Original data files were obtained from BADC. Here is a list of all file suffices and corresponding contents of files at BADC.

Error flagging:
0 Valid
1 Reduced Quality
2 Present but likely to be wrong or instrument not in measure mode, i.e. zeros or calibration
3 Completely invalid or missing data

The filename convention for C-130 files is heYYMMDD.sss
The suffices sss of files included in the ETHmeg database and corresponding contents are:

o36	O3
o1	Peroxides
fm1	HCHO
nxy	NO, NOy
cm1	CO
ps1	lat,lon,pressure altitude
tmp	p,T, dew point T
jn4	JNO2

The following problems were encountered during file processing:

• A few very high HCHO values of 144.xx ppb were recorded on flight 970920. These values were removed.
• Ozone values are close to zero during a few minutes after take-off. Is this real? For 1996 data these points were excluded, but they are still in the 1997 data.
• NOy is very high towards the end of flight 970410 after 14:48 UTC, probably due to pollution at the airport. These data have not been removed!
• No *.ps1 file is available for the last flight on 970923.
• File *.tmp is missing for some flights. Therefore pressure is derived from the pressure altitude parameter (assuming US standard atmosphere).
• Data has been restricted to pressures lower than 1005 hPa to exclude measurements before take-off and after landing. Additional data had to be excluded individually for each flight.
• The number of columns of *.fm1 files changes between April and September flights in 1997.
• Two different time formats were used in the files: seconds since 00:00 UTC and fractional julian days.
• One file (fm1 or po1 file?) in 1997 contained a few empty entries and was therefore read in wrong order. The defect rows were deleted.

Overview of measurement techniques and uncertainties

References