After slowing down yesterday evening, the wind picked up strongly during the night. This caused the largest snow drifts during the intensive phase so far to build up on the road to the Ridge Lab and the team almost got stuck. They were lucky to make it through a particularly large one on the third try and arrived at the lab at around 9:00 am. While the rest of the team went down to the weather station for lunch, Ellen stayed at the Ridge Lab until Pierre picked her up at close to 4:00 pm.
Leaving the Eureka Weather Station this morning, Sébastien and Erik were optimistic that the clouds would clear, giving them the opportunity to perform mid-infrared solar measurements with the Bruker 125HR. Throughout the morning, they noticed increasing clear skies so they started the solar tracker and prepared the Bruker for measurements by cooling the detectors with liquid nitrogen. Unfortunately, shortly after, the clouds reappeared and they were unable to start measurements. The partly cloudy skies later became completely overcast and as result no measurements were made.
The PEARL-GBS had an eventful morning. First, its shutter stopped working - a rather common occurrence, unfortunately. In order to replace the shutter, Kristof had to remove the diffraction grating, and after reassembling the instrument the grating failed to initialize properly. It took Kristof over half an hour to get the grating aligned again, but measurements eventually resumed just before 11 am. The UT-GBS was struggling with saturation, so Kristof placed a diffuser on the telescope, and the signal level went back to normal.
Due to the blowing snow, Ellen initially planned to take measurements using the globar and the HBr cell. Since the globar didn't seem to be at full brightness, she decided to swap it for another one, which unfortunately broke during installation. She reinstalled the original globar, but a glimpse of clear skies made her change her original plans and she set PARIS-IR up for solar measurements instead. Favourable conditions didn't last for long though, due to which PARIS-IR didn't take any measurements today. Apart from that, the instrument seems to be fine, as no further problems arose during the day. Ellen also used to afternoon to convert the rest of yesterday's measurements to interferograms and raw spectra.
The CRL continued measuring the same clouds seen yesterday for an hour at the beginning of 10 March UTC, and then continued measuring for the rest of the day as the skies cleared. Emily noted that some much smaller clouds populated the middle of the day, but nothing as thick as we've been seeing for the past few days. 24 hours of measurement were accumulated.
Peter and Ghazal went up to the Ridge Lab in the evening of 10 March. After one hour of operation, measurements had to be ceased, due to high wind speeds.
After several Ravens, today's ozonesonde was a latex balloon for a change. Its last information was received from an altitude of 32311 m to which it rose at an ascent rate of 201 m/minute.