Posted on 12/12/2015 8:29:30 PM PST by SunkenCiv
An international team of experts, including researchers from the Camborne School of Mines, have found evidence of a large and abrupt cooling of the Earth's temperature during the Jurassic Period, which lasted millions of years.
The scientists found that the cooling coincided with a large-scale volcanic event -- called the North Sea Dome -- which restricted the flow of ocean water and the associated heat that it carried from the equator towards the North Pole region.
The team suggest that it is this volcanic event, preventing the ocean flow, rather than a change in CO2 in the atmosphere (which causes today's climate change), that led to an extended Ice age in a period more synonymous with very warm conditions.
Geology experts Professor Stephen Hesselbo and Dr Clemens Ullmann, both from the Camborne School of Mines, based at Exeter's Penryn Campus in Cornwall, took part in the study.
Professor Hesselbo said: "We tend to think of the Jurassic as a warm 'greenhouse' world where high temperatures were governed by high atmospheric carbon dioxide contents. This new study suggests that re-organization of oceanic current patterns may also have triggered large scale climate changes."
...The team of scientists spent 10 years constructing a record of seawater temperature change using fossil mollusc shells. They found that during the same period that the North Sea Dome event occurred, the Earth experienced a significant and fast cooling in temperature...
Professor Hesselbo added: "Although we have known about the occurrence of cold periods during greenhouse times for a while, their origins have remained mysterious. This work suggests a mechanism at play that may also have been important for driving other climate change events in the Jurassic and at other times in Earth history."
(Excerpt) Read more at eurekalert.org ...
Ascent of dinosaurs linked to an iridium anomaly at the Triassic-Jurassic boundary -- Abstract
Olsen PE, Kent DV, Sues HD, Koeberl C, Huber H, Montanari A, Rainforth EC, Fowell SJ, Szajna MJ, Hartline BW.Analysis of tetrapod footprints and skeletal material from more than 70 localities in eastern North America shows that large theropod dinosaurs appeared less than 10,000 years after the Triassic-Jurassic boundary and less than 30,000 years after the last Triassic taxa, synchronous with a terrestrial mass extinction. This extraordinary turnover is associated with an iridium anomaly (up to 285 parts per trillion, with an average maximum of 141 parts per trillion) and a fern spore spike, suggesting that a bolide impact was the cause. Eastern North American dinosaurian diversity reached a stable maximum less than 100,000 years after the boundary, marking the establishment of dinosaur-dominated communities that prevailed for the next 135 million years.
More UK Gradualist Bull****.
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Academics are so predictable. Hopefully they'll all be murdered by Somalian pirates.
The team suggest that it is this volcanic event, preventing the ocean flow, rather than a change in CO2 in the atmosphere (which causes today’s climate change),
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Pure old horse manure.
An iridium anomaly in the Middle-Lower Jurassic of the Venetian Region, northern Italy -- AbstractOh, dang, they almost had it. ;')
Robert Rocchia, Daniel Boclet, Philippe Bont, Alberto Castellarin, Celestine JhannoA significant iridium enrichment has been found in a Jurassic marine sequence, about 180 million years old, outcropping in the Alps of the Venetian region. The maximum iridium concentration of 3.2 ± 0.2 ng·g-1 occurs in a brown crust 2-3 mm thick, containing essentially iron hydroxide. This crust, characterized by a nearly total absence of detritic components, lies on top of upper Lias limestones, and is overlaid with Bajocian-Bathonian limestones. The origin of the Ir anomaly is not clearly understood yet but could be explained by either a drop in the sedimentation rate resulting in the concentration within a thin sediment layer of the normally infalling cosmic dust and/or by an increase of cosmic material infall following an asteroid or comet impact(s).
Prove it.
Hahaha! Oh, I see, I see where they’re going with this-—buncha friggin’ assholes....
Chili Allosaurus, LWA
I thought we were hit by an iridium-rich meteor, and that that was settled science.
The British 'sciences' remain mired in gradualism and Darwinism, which will take some of the sting out of the eventual muzzie takeover there. Natural selection is, best case, a model for extinction -- but if most extinctions happen in large bunches, which is demonstrable, then there's no more need for a just-so story like natural selection. Their solution is Impact Denialism.
Shove it.
You should see the bucket of slaw that comes with that.
Hey, can’t win an argument with facts, resort to insults. Sounds like a RAT phony to me. A litle bit touchy there, eh?
Like I’ve always said....they’re all buddies....and having differing opinions fuels the grants. Just a bunch of ak’s
No, you’re just engaging in your usual rude troll behavior, which has been 100% unsoliticed, which is why you’re actually just another DNC plant.
Still never answered any of my questions. You never read your own articles. Have you read the Original jounal articles you post?
That would be a No. If you have, name the format of original journal articles and why each is important and structured as such. This is an easy question, they will get harder from here.
That was at the end of the Cretaceous period about 66 million years ago. This article is about an event 170 million years ago.
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