Contact: Eric Apel
Contact E-mail: apel@ucar.edu

Several volatile Organic Compounds (VOCs) were measured using the Trace Organic Gas Analyzer (TOGA). One-minute data is reported, but 40-second measurements were typically made every 5 or every 10 minutes, sampled during the first 40 seconds the minute in which they are reported. Sample times are reported in local standard time, AKST. The measurement sample height, Sampling_Height_feet indicate approximate sample heights, with the exception of 2, 6 and 18 feet locations.

The individual sample heights included in the data files represent the following (Note: the ground level at the sampling site is approximately 5m asl.)
0 Teflon line in snow or on snow surface
0.1 Sampling through a Teflon line attached to the TOGA 2 foot inlet on tower (April 4-9)
2 TOGA 2 foot inlet on tower
2.1 NOxyO3 manifold 2 foot tower (April 4-8)
6 TOGA 6 foot inlet on tower
6.1 NOxyO3 manifold 6 foot tower (April 4-8)
10.1 Silcosteel heated line above module on North side (April 9-14), approx. 5 feet above module roof
12.1 Teflon line above module on North Side (March 15-21), approx. 5 feet above module roof 18 TOGA 18 foot inlet on tower
18.1 NOxyO3 manifold 18 foot tower (April 4-8)
100 balloon (lowest) (April 4-8)
300 balloon middle (April 4-8)
500 balloon highest (April 4-8)
200 though balloon and/or NOxyO3 manifold, but potentially not working properly (i.e. balloon is not fully up yet, NOxyO3 is doing leak testing, etc.)
-9 none of the above (possibly due to calibration or zero)
-99999 not running VOC mixing ratios All mixing ratios are in pptv. Below detection limit
-8888 Data not available
-9999 Detection limits are less than 25 pptv.

Revisions: R6: all data has been revised to include one more significant figure, in the tenths decimal place, for increased precision in statistics. R5: revised data due to minor changes in the analysis of several intermittent time periods for VOC mixing ratios, both additions and subtractions, as well as changes due to previously inconsistent data reductions for acetaldehyde and methanol mixing ratios over the study. R4: additional data files have been integrated and added to the archive R3.