Mother-of-pearls over Oslo
With low sun the high-altitude clouds will glow in spectacular colours. The colours were special with pink and green as the most prominent.
NILU is part of several EU projects studying the formation and chemical composition of such clouds. This is part of our research on the depletion of ozone in the upper atmosphere.
The below picture show polar stratospheric clouds observed from NILU, Kjeller around sunset on 20. December 2002. Stratospheric temperatrues have been very low in December and PSCs have been observed in many places and with many techniques.