The team had plenty of troubleshooting and measurements to keep them busy during their first weekend at PEARL. The Eureka Weather Station celebrates the end of the week with brunch at 11 AM instead of the usual 7:30 AM breakfast.This enabled the team to enjoyed a couple of hours of extra sleep on Sunday morning and refresh their energy.
Temperatures outside have been holding relatively steady; the Ridge Lab has kept to about -31°C, and Eureka has been around -45°C. We received sunlight each day this weekend from about 10:30 AM until 3:30 PM.
In the PEARL Ridge Lab's IR lab, Dan took 34 measurements on Saturday and 24 on Sunday. Clouds on the horizon on Saturday limited solar measurements. The sky was clearer on Sunday; however, the Bruker computer kept spontaneously turning off. This limited measurement acquisition. The cause of this problem is not yet known, but Dan is investigating. He has also prioritized setting up the new Bruker computer.
The problem Dan experienced in trying to take cell measurements with the Bruker a few days ago has turned out to be a consequence of a problem with the cooler for the calibration light sources. If the Bruker senses insufficient cooling is available to the source lights, it cuts power to them to prevent damage. On Saturday, water suddenly appeared underneath the Bruker. Dan opened the cooler's cover and discovered a significant hole in the heat sink tubing, which was leaking water into the cooler's interior (and then leaking out a corner of the outer casing). This is frustrating, since we replaced the cooler during the last campaign due to leaks! On Sunday, Dan patched the hole and tested it for an hour and a half. It appears to be holding up. During the next cloudy day, he intends to try running cell tests again, while leaving the cooler cover off so he can closely monitor the cooler patch for leaking.
Dan also did a minor update of the suntracker code to help with the fitting of the solar image, following instructions from the always-helpful Jonathan.
On Saturday, Sebastien had trouble with the PARIS software, and did not end up with measurements. On Sunday, this was resolved and he took 10 measurements with PARIS. He has also been getting many static electricity shocks around the lab, but is developing techniques to lessen their impact. This experience is just part of working in a polar desert!
Xiaoyi spent Saturday fixing the PEARL-GBS filter wheel, which has been putting itself in the wrong position. He has also been improving its labview code. The new code will select filters based on both solar zenith angle and signal level. (The current code only uses solar zenith angle).
Xiaoyi and Paul added a second heater to the PEARL-GBS dome on the roof of the Ridge Lab. It is helping reduce the frost, which has been preventing measurements. The frost was mostly gone by 4 o'clock Sunday afternoon. The UT-GBS has been working without trouble all weekend, operating under the IR lab floor. (The instrument was moved there to help keep it cool). SAOZ is also working nominally; Florence has confirmed that the instrument and its spectra are in good shape.
Paul checked in on SPS throughout the weekend. It continues to operate normally.
ACE ozonesonde flights began tonight. This first ozonesonde flight reached an altitude of 32,234 m (5.9 hPa).
On Friday night, Paul and Dan went outside for about an hour to test taking photos of the night sky. It was a very clear night, and the view was fantastic.