WEATHER PHENOMENON: IRIDESCENCE OBSERVED OVER BRUNEI DARUSSALAM

04 Jun 2020

The Brunei Darussalam Meteorological Department (BDMD) would like to share with the public regarding the weather phenomenon known as Iridescence. It was briefly observed last Thursday, 4th June 2020 at Rimba, Gadong area around 6.00 pm.

Iridescence are the colours appearing on clouds, sometimes mingled and sometimes in the form of bands nearly parallel to the margin of the clouds. Green and pink occur most often, and in pastel shades. The iridescent colours are often brilliant, and resemble the colours observed on mother of pearl. Within about 10° from the Sun, diffraction is the main cause of iridescence. Beyond about 10°, however, interference is usually the predominant factor. Iridescence can extend to angles exceeding 40° from the Sun, and even at this angular distance, the colours may be brilliant.

Here in Brunei, this phenomenon is not frequently observed and tends to occur during fair weather accompanied by some high clouds. The picture shows iridescence occurring in the semi-transparent cirrostratus clouds made of tiny ice-crystals which scattered the light.

Cloud enthusiasts may share their collection of cloud pictures with us through our Facebook or Instagram pages @bruneiweather. Members of the general public may also
e-mail us at contact@met.gov.bn to know more or inquire about different clouds observed in Brunei Darussalam and also to contact our Duty Meteorological Forecaster at our
Weather Line 114 for more weather information.