| Description: | This instrument was refurbished at the the vendor's facility in 2008 and then sent to the
SGP for side-by-side comparison with another MWR. During the time the instrument was at
the SGP, it was noticed that the 23.8-GHz measurements were slightly warmer than those
from radiometer SN10 operating at the SGP Central Facility. A comparison with radiosonde
measurements confirmed the slight change in the measurements.
An explanation of the bias and comparison with radiosonde measurements and radiometer SN
10 is given in the mentor's monthly data review for the month of April 2008.
Since there aren't radiosondes at NSA.C2, it is difficult to work around this problem.
Based on comparison at the SGP, the bias in the 23.8-GHz channel was quantified to be ~1.5
K. Users can attempt to subtract this amount from the 23.8-GHz measurements.
Alternatively, use the retrieved PWV and LWV keeping in mind that there is a possible overestimation
of PWV of ~1 mm.
On 11/16/2009 after a hardware failure of the radiometer a spare radiometer (SN15) was
installed at the site. |