Another warm day with a high of 96F with winds mostly southerly, turning to northerly late in the day with increasing clouds. A brief rain storm in town late afternoon and lightning nearby, but only a trace reached the site.
Today was John's last day and he continued to help us with the wind profilers. This morning we erected a clutter fence for the Modular Profiler. The profiler is already in a chainlink fence compound which does provide some screening (and protection for anyone nearby), but we have found that installing sloped chainlink fence panels along the sides of the profiler (parallel to the polarization) does provide an effective clutter screen so we added that to the profiler here. We also installed acoustic surrounds for the RASS speakers. There was some improvement in the lowest range gates, and we are now getting wind measurements down to about 400m, compared to about 600 before. There is also a few dB reduction in interference to the sounding system. David set up a series of operating modes such as RIM and oversampling modes which we will test over the coming days, and John wired the RASS distribution. We also setup a shade cloth over the amplifier enclosure to keep it cooler.
On the MISS 915 MHz wind profiler, there appeared to be a problem with the antenna steering. Doppler spectra from opposing oblique beams appeared not to be the mirror images expected, suggesting that the antenna beam was not being steered correctly. The winds also appear to be rotated compared to the lidar and 449 MHz profiler. John checked the switching signals on the antenna cable with a multimeter and the beam steering codes seem to be correct. Reseating the cable appeared to help although we only had a short time to check it so we will do some more tests tomorrow.
Other tasks included tidying up cables, straightening the 10-meter met tower (it had been leaning a couple of degrees to the south) and tying things down in case of gusty winds (the nearby airport AWS reported gusts over 40 mph). Isabel got the VAD wind algorithm working for the windcube lidar, and she and Josh also worked on configuring the sounding system. We also paid a visit to the ISFS array of 50 towers, very impressive!
John departed and will soon will be heading to a new role in RSF, thanks very much for your help John!
Chainlink clutter fence panels on the 449 MHz Modular Profiler. Three panels were installed parallel to the polarization vector of the antenna.
Installing the RASS surrounds (left), diagnosing the MISS wind profiler (center), and visiting the ISFS tower array (right).