The ship from truck to water-line was as if cemented; spars, sails, blocks, and ropes were in a horrible state; but, thank God, no one was hurt, nor was the ship damaged. But think of Anjer, Merak, and other little villages on the Java coast! The northwestern part of Krakatoa Island had disappeared. The line of fracture began at a point south of Lang Island, and formed an arc of a circle passing through the peak to the western side of the island. Boats from the U.
Juniata entered the crater-like area, concave to the northward, and sounded along the face of the heights; but no bottom could be found with twenty fathoms of line. Prior to the eruption, Verlaten and Lang islands were green with trees and foliage; they are now covered with scoria. Eastward of Verlaten a small island had formed; small necks of land had been thrown out from the eastern side of Verlaten and the western point of Krakatoa.
The Polish Hat had disappeared, but a new rock, about twenty feet in height and as many in diameter, now existed in Krakatoa channel, near to the southern point of Lang Island. Within ten yards of this rock there were eight fathoms of water. At the place occupied by the Polish Hat the boats found no bottom with twenty fathoms of line, while at the spot where the volcano had been so active later soundings showed no bottom at one hundred and sixty-four fathoms, nearly one thousand feet.
To the northward and eastward two new islands, Steers and Calmeyer, had formed, where before the eruption were thirty to forty fathoms of water. It has been thought that the first great waves on the evening of the 26th were caused by a portion of Krakatoa being shot out northwards for eight miles, and dropped where now is Steers Island; while the terrific detonation on the 27th, and the greater wave accompanying it, resulted perhaps from that still more titanic effort which lifted the greater portion of Krakatoa, hurled it through the air over Lang Island, and plunged it into the sea where Calmeyer Island now blocks the old East Passage.
The captain of the Juniata stated in his report that he anchored off the site of Anjer, and that "the buoys which mark the line of the submarine cable to Telok Betong, Sumatra, and the base of the light-house at Fourth Point are the only monuments of Anjer. The plain northward of Anjer peak was swept by the flood of waters, and nothing remains but the vine-like roots of the cocoa palm and some scattered and ghastly relics of the inhabitants Communication with Telok Betong is now interrupted by masses of floating pumice wedged in Lampong Bay.
And yet another reported that on December 21, , in the S. The tidal phenomena which followed this convulsion are particularly interesting. The waves formed in the narrow strait issued into the oceans east and west, and started on their journey around the globe.
The undulations were registered at Mauritius, the Seychelles, in South Africa, and on the shores of the Pacific Islands on the same day that the Java villages were swept away. The waves continued their course, crossed each other at the antipodes of Krakatoa, and returned to the spot from which they had started.
Four times did they go around the earth before the equilibrium of the sea was so far restored as to be insensible to instruments. At the same time an atmospheric wave also started around the globe. These disturbances were noted wherever there were barographs, and the dates are thus fixed when these undulations passed various places on the surface of the earth. For instance, at St. Petersburg, on August 27th, there was a rise of the mercury, and immediately afterwards a fall. At Valencia, in Ireland, and at Coimbra, in Portugal, similar phenomena were noticed, and shortly afterward the disturbance was observed all over Europe, wherever a barograph was at hand.
At the western observatories the movement was more pronounced than at the eastern, but the general appearances of the curves at neighboring stations were about the same. This disturbance moved rapidly from east to west, requiring but two hours and twenty-five minutes to travel from St.
Petersburg to Valencia, a distance of thirteen hundred and fifty miles. On the 28th there was a somewhat similar disturbance which moved from west to east, requiring a little less than two hours to pass from Valencia to St. On the 29th there were two well-defined movements: one early in the morning, from east to west, occupying two hours and eight minutes from St. Petersburg to Valencia; and the other in the afternoon, from west to east, reaching St.
Petersburg one hour and twenty-five minutes after it was observed at Valencia. Similar phenomena, less defined, were noted on the 30th and 31st. Coincident with these atmospheric fluctuations, magnificent sunlight effects, lurid skies, prolonged dawns, and lengthened twilights were observed. He also reports that he noticed peculiar red sunsets in the South Atlantic several weeks before the Java eruption, and that he carried them through to Hong Kong, and from there nearly across to San Francisco.
The volcanic cloud that caused these peculiar effects seems to have followed a straight path, for they appeared on the east coast of Africa on the second day, on the Gold Coast on the third, at Trinidad on the sixth, and at Honolulu on the ninth day. It is impossible to say how high the lighter matter was carried; it is certain that months have been required for it to descend. The places situated below the direct path of the cloud were the first to have those ominous displays, which varied in intensity according to their time distance to the westward; for the cloud was at first elevated as a comparatively narrow column.
This column gradually spread out north and south, until the inhabitants of all lands obtained a view of the beautiful effects of broken and absorbed sunbeams, and a demonstration of the power of that steam which was imprisoned by the last convulsion of nature. We found a lack of proper tsunami defence structures or any early warning system, and houses and businesses built very close to the coast with no buffer zone.
We identified high ground where residents could run to in case of a tsunami and put up signs with evacuation routes. During this survey, I conducted a series of focus group meetings with local residents and businesses in order to make the communities more resilient and reduce their anxiety about future mega tsunamis in the area. I developed a tsunami wave propagation model to replicate the tsunami and most plausible future tsunami events, and to identify the most vulnerable coastal stretches, such as the village of Kunjir on the Lampung mainland.
I also combined field survey results, numerical model outputs and published information to make some recommendations for local communities. I suggested active collaboration between government departments and local institutions on the issue, and the formation of disaster preparedness teams for every village in Southern Lampung. The planning criteria for development of infrastructure along the coasts should also be put under review, and there should be a trauma healing programme for the victims of the Krakatoa tsunami.
But we should do what we can to prepare for the worst. Portsmouth Climate Festival — Portsmouth, Portsmouth. Edition: Available editions United Kingdom. The tasty camping food with fresh fish and overall excellent organization by our experienced local crew round up this trip into an unforgettable travel adventure. First visit to our site? Try our free app! Android iOS version.
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Hot upwelling mantle material forms magmas that continuously produce new oceanic crust. An ocean widens. Photos from Kamchatka Kamchatka in Russia's far east is one of world's remotest regions and has an almost unparalleled density of active volcanoes.
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