Today started with excitement during breakfast, as we found out the temperature outside the Eureka Weather Station had dropped below -50°C. Many of us took photos of the official temperature instrument in the Weather Office. The temperature outside the PEARL Ridge Lab was warmer, at -38°C, and the sky was cloudless. Conditions were perfect for solar atmospheric measurements!
Dan, Debora, and Joseph had a highly productive day of solar measurements in the Ridge Lab's IR lab. The Bruker and PARIS began measurements shortly past 10 AM, and continued throughout the day until nearly 4 PM. In total, PARIS took 36 measurements and the Bruker took 55 MIR measurements. A brief pause occurred mid-afternoon because the suntracker became stuck. This was quickly resolved, and measurements continued. We speculate this occurred because the suntracker had been idle for many cold months before its first full day of use.
Over in the UV-Vis Lab, Xiaoyi's SAOZ and PEARL-GBS continued taking measurements nominally. Since the UT-GBS's CCD had been saturating yesterday, Xiaoyi worked on realigning its CCD and fiber bundle. He also performed standard testing on the UT-GBS again, since he had modified components of the optical system. By the end of the day, Xiaoyi had tested the UT-GBS in sunlight again. Its signal is now in a reasonable range. He has left the UT-GBS running dark current tests overnight. Xiaoyi also fixed the new GBS shutter's connectors. These 5 shutters were purchased last month, but yesterday Xiaoyi discovered their connectors did not function. He has fixed and tested all 5 new shutters. This is great news.
Today, Volodya reorganized the SPS and MAESTRO software so that they collect data in their own directories. He also verified the pointing to the Sun is good, ran MAESTRO and SPS measurements, and made modifications to allow instruments to talk to each other. At the end of the day, Jim installed a remotely controlled power bar so that the instruments can be restarted using a computer from the Eureka Weather Station.
Down at 0PAL, Zen finished performing maintenance on the E-AERI and monitored the hatch problem. It appears the digital rain sensor has failed. Zen edited the E-AERI's software so that it uses the analogue rain sensor to determine when the hatch should close, and ignore the broken digital sensor. Based on one day of observation, the hatch appears to be working properly. The E-AERI took continuous measurements all day. Zen still needs to adjust the fine-tuning of the analogue sensor.
Chris ran 0PAL's lidar remotely from Halifax today. It has been running continuously since 9 PM last night, and is still operating well. Emily spent the day verifying and documenting yesterday's calibration, and updated the analysis code to account for the new 2013 measurements. Chris posted the first day's measurements on the lab group's public website, which can be found here.
Emily also visited the Eureka Weather Office and learned about ozonesondes and radiosondes. These are an important part of the ACE Validation Campaign, and she was interested to learn as much as she could about them. Jane, an Environment Canada Meteorological Technician, showed her how to perform daily sonde preparation. This involved checking its sensitive to ozone, and checking the pump's flow rate. Later in the afternoon, James, the Eureka Weather Station's Senior Aerological Observer, showed her how to test radiosondes. The sonde needs to be initialized to read room temperature and pressure, and checked to ensure the sonde transmits data to the computer properly. The ozonesonde and radiosonde flew together on a Raven balloon this evening.
Jane and Emily also went for a fantastic walk on the fjord after lunch. We did not see any critters (although they saw many tracks, and places where bunnies had been digging), but the Sun was up, it was -50°C, and there was very little wind. This made for a pleasant excursion. They enjoyed the variety of sounds produced simply by walking over different kinds of sea ice. Sounds traveled very effectively. They heard echoes of their own voices. There were no buildings or tall rocks very nearby, and they were not speaking very loudly, so they surmised that the echoes were caused by the very cold air temperatures.
The first ACE ozonesonde flight occurred today at 18:15 local time and reached an altitude of 31,655 m.
This has been a fantastic day for measurements. The team hopes today's great weather continues throughout the campaign!