January 9, 2013
Following the SCP project, we tested each sonic in a zero-wind enclosure within the EOL temperature chamber, measuring wind component offsets and sonic temperature errors over the nominal range -30 C to 55 C. The following table shows wind component offsets as okay if the u and v offsets are less than +/- 4 cm/s and the w offsets less than +/- 2 cm/s (between - 20 C and 30 C). The sonic temperature corrections are listed as the slope and offset of a linear fit (between -20 C and 30 C), tc.sonic = offset + slope*Tc, where Tc is calculated from temperature, relative humidity, and pressure measured in the zero-wind enclosure.
Sonic |
Location |
Cal date |
u |
v |
w |
tc offset (degC) |
tc slope |
|---|---|---|---|---|---|---|---|
0200 |
c.1m |
6/27/12 |
ok |
ok |
ok |
0.04 |
0.9812 |
0197 |
c.2m |
7/3/12 |
ok |
ok |
ok |
-0.74 |
1.0101 |
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