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 Ellington ( 29.61, 95.17) ACCENT 1 1 1999 09 13 1999 09 13 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. Ellington 22 007 29.61 95.17 0.0 288.2 1.1 1.5 0.6 60741 16 52 21 1.186 289.4 2.5 1.8 0.8 5 61851 17 10 51 1.155 287.2 2.3 1.6 0.7 5 62336 17 18 56 1.144 286.5 4.1 2.4 0.7 5 63309 17 35 09 1.127 286.5 4.5 2.0 1.0 5 68068 18 54 28 1.125 286.5 3.2 3.0 1.1 5 70358 19 32 38 1.171 287.2 2.0 2.1 0.5 5 70841 19 40 41 1.185 288.6 2.3 1.9 0.7 5 71325 19 48 45 1.202 288.6 1.7 1.5 0.7 5 72758 20 12 38 1.262 287.1 1.9 2.3 0.7 5 73242 20 20 42 1.286 288.6 3.5 1.8 1.0 5 74302 20 38 22 1.349 289.1 2.3 1.1 0.7 5 75449 20 57 29 1.434 287.4 1.9 2.3 0.9 5 75935 21 05 35 1.477 289.5 2.1 1.4 0.5 5 76503 21 15 03 1.532 290.8 2.6 1.1 0.5 5 77458 21 30 58 1.641 288.7 1.7 1.4 0.4 5 78307 21 45 07 1.758 289.2 1.2 1.1 0.4 5 78796 21 53 16 1.837 288.5 0.9 1.3 0.1 5 79367 22 02 47 1.941 289.1 1.4 1.2 0.5 5 80893 22 28 13 2.307 288.1 0.3 0.5 0.1 5 81377 22 36 17 2.459 288.2 1.1 0.8 0.3 5 81861 22 44 21 2.635 287.9 1.6 0.9 0.5 5 82534 22 55 34 2.931 287.1 1.6 0.3 0.6 5