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 Moffet Field ( 37.25, 122.03) STRAT 1 1 1995 10 21 1995 10 21 0 12 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. Moffet Field 22 009 37.25 122.03 0.0 278.2 6.1 -1.7 0.9 64362 17 52 42 1.757 279.3 0.6 -1.9 0.2 5 66537 18 28 57 1.610 270.1 1.5 -0.3 0.4 5 71387 19 49 47 1.488 271.4 2.3 -0.9 0.6 5 72818 20 13 38 1.495 270.6 0.9 -0.7 0.3 5 73287 20 21 27 1.501 271.5 1.0 -0.8 0.3 5 73798 20 29 58 1.511 269.9 1.1 -0.4 0.4 5 74520 20 42 00 1.528 288.5 0.9 -3.2 0.2 5 75032 20 50 32 1.544 287.9 0.7 -3.0 0.3 5 75841 21 04 01 1.575 285.1 2.2 -2.6 0.4 5 76353 21 12 33 1.599 285.9 3.3 -3.0 0.8 5 77074 21 24 34 1.637 284.5 1.5 -2.6 0.5 5 77586 21 33 06 1.669 284.5 0.8 -2.4 0.2 5 78600 21 50 00 1.746 283.4 1.7 -2.4 0.4 5 79113 21 58 33 1.791 281.9 0.7 -1.9 0.3 5 79835 22 10 35 1.865 281.3 0.7 -1.9 0.3 5 80351 22 19 11 1.925 281.1 0.9 -2.4 0.2 5 81072 22 31 12 2.022 277.4 0.7 -1.6 0.2 5 81583 22 39 43 2.101 277.1 0.6 -1.5 0.1 5 82305 22 51 45 2.231 275.7 0.7 -1.1 0.2 5 82817 23 00 17 2.338 274.4 1.0 -1.0 0.3 5 83445 23 10 45 2.489 273.4 0.9 -1.1 0.4 5 83958 23 19 18 2.633 273.1 0.8 -1.1 0.1 5