The weather was -40°C at PEARL today, but there was not any significant wind. The Eureka Weather Station was slightly colder, at -45°C. Unfortunately, it was also cloudy, which prevented solar measurements.
In the PEARL Ridge Lab's IR lab, Joseph and Dan made good use of the cloudy day to perform HBr cell tests. Combined with the HCl tests performed yesterday, the Bruker's ILS and modulation efficiency have been characterized and confirmed to be good. Debora tried to take atmospheric measurements with PARIS, but the clouds blocking the Sun rendered them too noisy to be useful. She took additional background measurements instead.
In the UV-Vis Lab, Xiaoyi started to take measurements with the UT-GBS. It received too much signal, so he is working on a solution. In the meantime, the UT-GBS is taking Zenith-sky measurements in a limited region of the CCD. Xiaoyi also installed a new SAOZ cable. SAOZ is now taking data, and initial spectra look good. The PEARL-GBS continues to operate well in combination mode.
Also at the Ridge Lab, Volodya adjusted the solar pointing of the SPS and MAESTRO and verified that the tracking is accurate. SPS and MAESTRO are now ready for observations once the weather improves.
Down at 0PAL, Zen opened, inspected, cleaned, and reassembled the E-AERI's front end, and resumed measurements. The E-AERI hatch continues to close randomly. Zen edited the software script to switch rain sensors, and hopes this will fix the issue.
Emily, also at 0PAL, performed laser beam and optics inspections after the first full night of lidar operations. She also completed diagnostic tests to ensure the quality of the laser signal. Following that, Chris did an alignment of the lidar remotely from Halifax. The rest of the day (and into the evening), they performed polarotor calibrations. This will ensure the polarizer is aligned in the optimal orientation for depolarization measurements.
ACE ozonesonde flights begin tomorrow (February 28).
With all instruments ready to perform nominal measurements (except the UT-GBS), the team is hoping for good weather tomorrow!