Supplement for A case study of a quasi-stationary, very long Polar Stratospheric Cloud layer edge

Polar Stratospheric Clouds (PSCs) are a common phenomenon during Arctic and Antarctic wintertime. Images of PSCs were obtained in Northern Scandinavia (Kiruna, Sweden) for the period of 2006-2020. Various types (Types I and II) of PSCs can be seen in the images. Based on those observations it can be concluded that PSCs with patchy structures are common over Kiruna, while well-defined cloud boundaries are a rare exception.