On Saturday, March 2nd the temperatures at the Eureka weather station were around -21 degrees C, with winds of 13 knots (24 km/h), giving a windchill temperature of -32 degrees C. Temperature at the Pearl Ridge Lab on Saturday were lower than Eureka (which is not usually the case), at -24 degrees C with high winds of 26 knots (48 km/h), bringing the windchill index to -41 degrees C. Saturday was another cloudy day, and with ice crystals falling throughout the day. The drive back to Eureka from PEARL at the end of the day was a difficult one, as the strong winds were blowing significant quantities of snow across the road, limiting the visibility to just a few meters at times. However, thanks to Pierre’s experience in driving in these harsh conditions, the team made it back safely. Just under 7 hours of sunlight were expected, but the sun never managed to break through the clouds.
Due to the cloudy conditions, Sebastien and Tyler were unable to begin solar measurements, so they spent the day finishing up the N2O cell tests with the 1mm aperture, and they ran an additional HBr cell test to confirm the success of the alignment process. So far, the results of all of the cell tests have been extremely promising, and the previous mis-alignment issues of the aperture wheels appear to have been fixed.
Kristof spent his day finishing off the PEARL-GBS lab tests, and then he analyzed the data. He confirmed that the results looked similar to last year's tests, and then he reconnected the instrument to the tracker on the roof before restarting measurements.
In the morning, Xin collected two bottles of blowing snow from the tray mounted outside of the 0PAL. Due to the strong winds at the PEARL Ridge Lab, Xin was unable to collect samples there. In the afternoon, Xin and John visited the sampling sites to the west of the Eureka Weather Station. Following the blowing snow event on Friday, Xin found it difficult to locate his sampling points from the previous day. Later in the afternoon back at the 0PAL, Xin tested the conductivity of several of his snow samples to analyze them for salinity.
Ali spent the morning looking at measurements collected by Tom’s SPS in the previous 24 hours, to ensure that the instrument is operating properly and that the signal was strong. Due to the cloudy conditions on Saturday, the instrument’s signal was quite low and the spectral features were weaker as a result.
The winds eased up later in the evening, and the scheduled produce flight managed to land at the Eureka airstrip just before 7pm (local time), bringing with it fresh fruits and vegetables to keep the Weather Station staff and the campaign team well-fed, as well as a new instrument to be installed in the IR lab at PEARL, the Bruker EM27/SUN infrared spectrometer. Three members of the campaign, Alexey, Tom and Sebastien, as well as one of the CANDAC operators, John, boarded the flight which was bound for Yellowknife. After all of the produce had been unloaded and the plane was refuelled, it departed to head back south shortly before 8pm.
On Sunday, March 3rd the temperature at the Eureka weather station was -30 degrees C, with light winds of 5.9 knots (11 km/h), bringing the windchill temperature to -39 degrees C. The temperatures at the Pearl Ridge Lab was stayed around -18.6 degrees C, with calm winds of 7 knots (8 km/h), bringing the windchill index to -26.5 degrees C. Sunday was a beautiful clear, sunny day, with a total of 7 hours and 14 minutes of sunlight.
In the IR lab, Tyler began the day by starting up the Bruker 125HR to take the first set of solar measurements of the year, and then spent the remainder of his afternoon unpacking and setting up the new EM27/SUN in the infrared lab. A portion of the solar beam used for the Bruker 125HR will be re-directed towards the EM27 using a pick-off mirror, and it will be making near-infrared solar absorption spectra measurements.
Since the sun finally made its return, Kristof was able to start the Pandora alignment procedure. The instrument determines the location of the sun (using intensities from azimuth and elevation scans), every few minutes during the day to establish the precise orientation of the tracker. After a few more sunny days, there should be enough data to fully characterize how level the tracker is (and what corrections are needed for each azimuth), and then he will be able to start measurements.
Today Xin collected two bottles of blowing snow samples from the tray which he set up at 0PAL, which were a result of yesterday afternoon’s strong blowing snow event. He also managed to collect enough samples at PEARL to fill up two 50 ml vessels. With the help of the newly arrived CANDAC operator Peter, Xin collected surface snow samples from three sampling sites. Back at 0PAL, Xin continued his salinity analysis, and melted some of his samples before measuring their conductivities. All of the samples which he melted were subsequently re-frozen after his analysis.
Ali continued to monitor the data from the SPS as he is the primary operator of the instrument now that Tom has headed back down south. He spent the remainder of his afternoon working on his temperature retrieval algorithm for the vibrational DIAL data.
Cheers,
Tyler Wizenberg
[On Behalf of the 2019 Canadian Arctic ACE/OSIRIS
Validation Campaign team]
* Instrument Status *
Bruker FTIR: Nominal operations
EM/27 SUN FTIR: In transit to Eureka
Ozonesonde: No balloons were launched on Saturday due to high winds. An attempt was made at launching a Raven at 6:15pm (local time) on Sunday, but winds caused the payload to drag along the ground, and ultimately no signal was received from the instrument.