55 2160 McElroy, Tom;Midwinter, Clive;Barton, David;Hall, Bob;Kerr, James;Wardle, David ENVIRONMENT CANADA, Dowsview, Ontario, CANADA M3H 5T4 (416) 739-4630 Brewer Ozone Spectrophotometer data at Moffett Field ( 37.42, 122.58) STRAT 1 1 1996 02 01 1996 02 01 0 13 elapsed time in UT seconds from 0000 hours on the day given in DATE Station name 9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 99 99 99 999 999 999 999 999 999 hour minute second airmass ozone [DU] (Dobson Units) ozone error [DU] (Dobson Units) SO2 [DU] (Dobson Units) SO2 error [DU] (Dobson Units) Number of data points in row 9 0 1 1 1 1 1 1 1 1 1 99 9999 999 999 99999 999 999 999 999 number of observations instrument number station latitude (degrees) station longitude (degrees) station elevation (m) daily mean O3 [DU] (Dobson Units) daily mean O3 error [DU] (Dobson Units) daily mean SO2 [DU] (Dobson Units) daily mean SO2 error [DU] (Dobson Units) 1 *** preliminary data *** 16 The Brewer Ozone Spectrophotometer is a 15-cm focal-length, modified Ebert-Fastie spectrograph which makes rapid, time-multiplexed measurements in the UV-B region of the solar spectrum. A typical direct sun observation is the average of 5 separate observations. If the standard deviation of the measurements is less than 2 DU, the measurement is taken as acceptable. If the standard deviation is larger, it is interpreted as indicating variability of the solar intensity, i.e.: clouds or other optical attenuation. Each of the five ozone measurements which contributes to the average value are composed of 40 short observation samples. A cycle of 2 samples on each of the five wavelengths takes place in about 1.2 seconds. The usual measurement of 20 cycles takes under 30 seconds. Daily averages are calcluted using all good observations and are reported as the last line in the data table. Moffett Field 22 009 37.42 122.58 0.0 347.4 2.4 -2.2 0.3 63096 17 31 36 2.611 342.4 1.0 -1.9 0.3 5 63928 17 45 28 2.424 344.8 0.9 -2.4 0.3 5 64440 17 54 00 2.327 345.4 0.9 -2.1 0.3 5 64951 18 02 31 2.241 345.2 0.6 -2.1 0.1 5 66164 18 22 44 2.076 345.7 1.3 -2.0 0.3 5 66679 18 31 19 2.018 347.9 1.0 -2.7 0.2 5 67190 18 39 50 1.968 347.5 0.7 -2.3 0.3 5 68927 19 08 47 1.838 347.6 1.1 -2.4 0.2 5 69653 19 20 53 1.799 348.0 1.2 -2.1 0.1 5 70164 19 29 24 1.776 350.0 0.4 -2.4 0.2 5 70890 19 41 30 1.750 348.2 1.2 -1.9 0.4 5 71615 19 53 35 1.732 350.5 1.7 -2.5 0.4 5 72863 20 14 23 1.714 348.9 2.2 -2.1 0.6 5 73597 20 26 37 1.712 342.2 2.1 -1.6 0.5 5 74614 20 43 34 1.719 348.6 2.2 -2.9 0.8 5 75126 20 52 06 1.728 349.4 0.6 -2.0 0.1 5 75852 21 04 12 1.746 350.2 2.0 -2.1 0.5 5 76871 21 21 11 1.782 349.8 1.2 -2.4 0.3 5 77382 21 29 42 1.806 349.1 0.9 -2.3 0.4 5 78107 21 41 47 1.846 349.3 1.0 -2.5 0.2 5 79124 21 58 44 1.918 346.0 0.5 -2.2 0.4 5 79637 22 07 17 1.962 345.6 1.3 -1.6 0.3 5