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Sighting along the PAM masts, the orientation of the upwind array is 39.6 221 deg and the downwind array is 39.2 40 deg.  Adding 90 and 270 degrees and the declination (13.7 deg) gives 323324.3 7 degrees true for the upwind array and 322323.9 7 deg true for the downwind array, which is are close to the design value of 325 deg.    

Note that the datascope had the wrong declination (but don't know what value was used for the site survey), 13.4 degrees rather than  13.7 degrees, which may account for 0.3 degrees of the differences of 1.7 and 2.1 degrees.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.

The tables list three or more Tables list three 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 remeasured the azimuths done prior to 7/11/08.

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

 Upwind Array Sonics

Profile tower Sonics

Downwind Array, top sonics

Downwind Array, bottom sonics