The AeroVironment Model 4000 Mini-SODAR was installed on the roof of the
Bennett Federal Building (located at approximately 110 South, 50 East).  The
roof mounting placed the mini-SODAR at a height of 30 m above ground level
(AGL), well out of the urban canyon, but within the urban canopy.  Data
acquisition started at 1220 Mountain Standard Time (MST) on 28 September.  All
data were tagged with time in MST, with the time in the filename indicating
the end of the 10-min data acquisition period.  Significant SODAR settings
included a maximum range of 200 m in 5-m range gates, starting at 15 m above
the antenna, and an averaging time of 600 s.  The signal-to-noise ratio for
assessing data quality was set at 7.

The original SODAR location was on the north edge of the roof, 20 m west of
the east edge of the roof.  The SODAR Y-axis, which is used for alignment, was
oriented towards the east (90 with respect to true north).  Fixed echoes from
surrounding structures degraded data quality with this alignment.  At 1420 MST
on 5 October, the SODAR was moved to the northeast corner of the Federal
Building roof and oriented towards north.  This relocation eliminated most of
the low-elevation fixed echoes, but a strong fixed echo remained at 150 m.
The acquisition of good quality data to roughly 100 m began at 1520 MST on
5 October.  During a site visit on 6 October, Dr. Rich Coulter suggested
baffling the exterior of the SODAR�s bounce board.  This was accomplished on
the next day using a sheet of particleboard and old floor padding.  Following
installation of this material at 1050 MST on 7 October, no fixed echoes were
observed through the remainder of the measurement period.  Unfortunately,
because the antenna azimuth angle was not reset after the SODAR was moved to
its new location, all of the data collected from this site after the 5 October
move required a -90 correction.  This correction has been incorporated into the
derived data sets referenced in this document.  Figure 1 shows the Model 4000
SODAR placed in its final location on the roof of the Bennett Federal Building.