LIDAR observations of nickel – An update
By Shane Daly on Wednesday, January 17th, 2018
A return journey was made to Kühlungsborn from mid-September to mid-October. The goal was to continue lidar measurements but for nickel (Ni) this time rather than aluminium oxide (AlO). During the March-May 2017 observations, no observable AlO layer was measured. Instead an upper limit value of AlO was obtained which entailed taking the detection limit at an altitude where the layer peak would be expected. This upper limit is still very useful for computational models.
So back to Ni. An initial issue we had with Ni measurements was the excitation wavelength as the dye laser struggled to operate at 337 nm. This problem was initial solved by removing the dye laser’s internal etalon. From there we carried out a series of measurements for Ni on multiple nights to no avail. However all hope wasn’t lost. Measurements continued in Germany even after I returned to Leeds.
Finally, on the 7th January we received the good news!
Looking at a different Ni wavelength transition, a measured resonance layer was recorded. Further observations were made on the 8th & 14th January. The resonance layer was ~4 times smaller than the first measurements made in Alaska back in 2012 but nonetheless proves that the layer does indeed exist.
Research is currently ongoing. Stay tuned!