PSC_Kiruna_WEB.tar: 
This contains photographs of Polar Stratospheric Clouds (PSCs) taken over Kiruna during 2006-2020. 

Figure1_left_original.jpg: 
The photograph shown in Figure 1 (left). 

Figure1_right_original.jpg: 
The photograph shown in Figure 1 (right). 

170213-14_signals.mat: 
A MATLAB file for the lidar data on 13-14 February 2017 shown in Figure 3.