The Krakatoa sunrises and sunsets

[Weather-history]

Here are some reports on the beautiful sunrises and sunsets that were seen around the world after the cataclysmic eruption of Krakatoa during late August 1883.

Woolstaston: "The remarkable chromatic effects in the sky at sunrise and sunset were truely magnificent during the greater part of the month especially at sunset on the 4th, when the moon appeared a bright green moon."

Orleton: " The yellow light before sunrise and after sunset was visible everytime the sky was clear."

Boston: " The sunsets throughout the month were very remarkable and of a most brilliant character."

Killingholme: "There was an unusual glow before sunrise on two or three mornings ."

Haverfordwest: "the sunsets were gorgeous, every variety of colour blending indescribably"

Aberdeen: " The most notable phenomena during the month (Dec) were the gorgeous sunrises and sunsets."

Sunderland: "... great pink semicircle opposite the sun which is at its best about 20 minutes before sunrise and after sunset. It consists of the upper half of a very broad bright ring, whose outer radius is about 25 degrees and inner about half that.."

Lerwick: "I have noticed the clouds in the evening assuming colours which I never saw them before, viz, a deep sea green, such as you may have noticed on fresh water slime in stagnant pools in summer.

The sky from the west to the southeast was all a very deep sea green and the moon actually appeared green."

[knocker]

Just a couple of additional comments.

A notable consequence of the eruption was the discovery, in 1885, of noctilucent clouds. These clouds had never been observed before, which appeared after the eruption at very high altitudes. Otto Jesse and a team from the Berlin Astronomical Society observed and photographed these clouds for many years.

Talking of Berlin, the event also marked the beginning of modern upper-atmospheric research and led to the instigation of the Berlin Atmospheric Research Programme.

[knocker]

Digressing for the moment, if that’s possible, from the weather to another puzzle regarding the eruption.

Very quickly after the eruption what was left of the island began to be recolonised. First by insects, then snakes and finally plants and reptiles. But one unanswered question has been the growth of fig trees. Fig plants can only be pollinated by female wasps of a particular species (one for each fig species). So how do fig trees colonise an island without the wasps they need, and how do the wasps colonise an island without the figs they need? The question, as far as I know, remains unanswered.

Edited April 22, 2011 by weather ship

[Weather-history]

Sept 1883

Mauritius: The clouds and sky at sunrise and sunset were coloured more frequently and to a greater extent than usual; probably partly to the presence of volcanic dust from Sunda.

Colombo: From the 8th to 15th the rising and setting sun was of an unusual green colour.

Barbados: The sun appeared various colours on the evening of the 15th and morning of 16th.

Oct 1883

Mauritius: Unusually prolonged and intense colourations of the sky before sunrise and after sunset every day lasting 75 minutes.

Adelaide: On every clear evening during this morning and the last fortnight of september, a peculiar phenomenon has been apparent in the western sky. Shortly after sunset, a red glow will make its appearance at an altitude of 50 degrees being very faint at first but as the brightness of the sky near the horizon dies away with the receding sun, the red glow will expand downwards, becoming at the same time more brilliant until at last the whole western sky will be lit up with a beautiful light, varying in colour, from a delicate pink to a most intense scarlet and the spectacle presents a most brilliant spectacle. The upper part will gradually fade away until the colour is noticeable only 8 degrees above the horizon, ay which time the light is at its brightest. Afterwards a secondary glow will sometimes make its appearance at an altitude of 50 degrees and gradually spread downwards until the sky is again lit up. The whole thing will fade away about 8pm.