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Sighting along the PAM masts, the orientation of the upwind array is 221 deg and the downwind array is 40 deg. Adding 90 and 270 degrees and the declination (13.7 deg) gives 324.7 degrees true for the upwind array and 323.7 deg true for the downwind array, which are close to the design value of 325 deg.
Note that the tripods for the second upwind array are already set up roughly N of the profile tower. The data scope gives an angle of 156 deg magnetic from the leg of the SW tripod to the profile sonics, so the profile winds from directions greater than 156+180 + 13.7 = 349.7 deg true should be used with caution.
Tables The tables list three or more independent measurements of sonic azimuth. I measured each row at different times, requiring independent estimates of proper alignment of the datascope relative to the sonic, which is the biggest source of uncertainty. I found that the sun angle is much better for visibility of the sonics at 7 am than at 10 am, so I reshot remeasured the azimuths done prior to 7/11/08.
The The cal_file entries are the value used for the sonic azimuth in the cal_files in order to give winds in a coordinate system with the sonic u component normal to the array (positive for winds blowing into the array sonics) and v parallel to the array: use + 13.7 - (325-180) = use - 131.7
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date | 3u | 4u | 5u | 6u | 7u | 8u | 9u | 10u | 11u |
|---|---|---|---|---|---|---|---|---|---|
7/6 | 133.6 | 136.5 | 133.3 | 134.3 | 135.3 | NA | 133.9 | 134.9 | 133.1 |
7/6 | 133.4 | 135.8 | 132.3 | 134.4 | 134.8 | 132.4 | 133.2 | 134.0 | 133.7 |
7/6 | 133.0 | 135.4 | 132.1 | 134.4 | 134.7 | 134.0 | 131.8 | 132.8 | 132.3 |
7/14 | 133.2 | 133.6 | 132.0 | 132.2 | 134.0 | 133.3 | 132.6 | 132.3 | 132.6 |
7/14 | 132.8 | 135.0 | 131.6 | 132.5 | 133.2 | 131.5 | 132.9 | 132.6 | 132.4 |
7/14 | 132.6 | 135.0 | 132.1 | 132.3 | 133.5 | 132.0 | 132.8 | 132.2 | 131.3 |
use | 132.9 | 135.0 | 132.1 | 132.3 | 133.6 | 132.3 | 132.8 | 132.4 | 132.1 |
cal_file | 1.2 | 3.3 | 0.4 | 0.6 | 1.9 | 0.6 | 1.1 | 0.7 | 0.4 |
Profile tower Sonics
date | 1.5m | 3m | 4m | 5.5m | 7m | 8m |
|---|---|---|---|---|---|---|
7/8 | 132.4 | 135.8 | 133.6 | 135.9 | 128.8 | 131.2 |
7/8 | 132.9 | 136.7 | 133.4 | 134.0 | 130.7 | 133.0 |
7/8 | 132.2 | 136.3 | 133.8 | 133.1 | 130.3 | 132.0 |
7/13 | 132.5 | 136.0 | 133.9 | 133.5 | 133.9 | 129.2 |
7/13 | 132.1 | 134.5 | 133.1 | 135.6 | 134.0 | 134.6 |
7/13 | 132.0 | 136.0 | 133.7 | 135.1 | 134.1 | 135.7 |
use | 132.3 | 136.0 | 133.6 | 134.6 | 134.0 | 132.6 |
cal_file | 0.6 | 4.3 | 1.9 | 2.9 | 2.3 | 0.9 |
Downwind Array, top sonics
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