Photo Credit: Courtesy Image
Posted on 03/16/2019 10:59:38 AM PDT by SunkenCiv
When UC Santa Barbara geology professor emeritus James Kennett and colleagues set out years ago to examine signs of a major cosmic impact that occurred toward the end of the Pleistocene epoch, little did they know just how far-reaching the projected climatic effect would be... the Younger Dryas Impact Hypothesis, which postulates that a fragmented comet slammed into the Earth close to 12,800 years ago, causing rapid climatic changes, megafaunal extinctions, sudden human population decrease and cultural shifts and widespread wildfires (biomass burning)... suggests a possible triggering mechanism for the abrupt changes in climate at that time, in particular a rapid cooling in the Northern Hemisphere, called the Younger Dryas, amid a general global trend of natural warming and ice sheet melting evidenced by changes in the fossil and sediment record.
Controversial from the time it was proposed, the hypothesis even now continues to be contested by those who prefer to attribute the end-Pleistocene reversal in warming entirely to terrestrial causes. But Kennett and fellow stalwarts of the Younger Dryas Boundary (YDB) Impact Hypothesis, as it is also known, have recently received a major boost: the discovery of a very young, 31-kilometer-wide impact crater beneath the Greenland ice sheet... Kennett and colleagues, led by Chilean paleontologist Mario Pino, present further evidence of a cosmic impact, this time far south of the equator, that likely lead to biomass burning, climate change and megafaunal extinctions nearly 13,000 years ago.
"We have identified the YDB layer at high latitudes in the Southern Hemisphere at near 41 degrees south, close to the tip of South America," Kennett said. This is a major expansion of the extent of the YDB event." The vast majority of evidence to date, he added, has been found in the Northern Hemisphere.
(Excerpt) Read more at news.ucsb.edu ...
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Simon Warwick-Smith
Not to be picky... but...
Whenever artists show meteor or comet impacts, they invariably show the incoming body “burning” brightly many hundreds or thousands of miles up in altitude.
This does not occur in sweet reality. The “burn” begins well UNDER 100 miles up. The burn only lasts very briefly, because the objects are moving very, very fast, indeed. Tens of thousands of miles an hour. Many miles a second.
From the beginning of the burn to impact is a matter or only a few seconds at most. During that time, the heat of entering the atmosphere is both sudden and extreme — which is one reason why so very much heat energy is liberated and why the objects often explode with a colossal blast. The deceleration in Gs is fabulous. Thousands of Gs is a force like hitting a brick wall.
To me, this seems even more awe-inspiring than the long burn depiction.
Picky, I know — but the real effect is truly amazing.
Hope you never see one!
Now That’s global warning!
I saw a fireball about 10 years ago. Green flame and smoke as it moved (apparently) slowly across the sky. Looked to be 2 or 3 thousand feet up but in reality maybe 100 miles. People called in to report an airplane burning. It was spectacular.
I haven’t seen an explanation for the evidence that there was cooling in the northern hemisphere and warming in the southern in the same time frame.
So the world got much hotter, then an ice age occurred because of the dust particles. Then it gradually moved back to the world as it was. We still have a long way to go before the world gets back to its natural hotter state.
But there are scientists who, with the government funding, are trying to change the world back to the way it was. Not the way it was 14,000 years ago. They want it to be the way it was when they were young. They were born into the world and they want to preserve the world in a state of frozen animation, like some super park rangers. There are groups that want to cover the ice sheets in gigantic clothe sheets. There are scientists that want to shoot clouds of tiny iron particles into the upper atmosphere to reflect the suns rays. Nothing could go wrong there, right?
The world has gotten far hotter than it is now. And its been far colder. Our scientists should watch it. But changing it or claiming they understand it, is crazy. Nobody is able to come to a stupid conclusion faster than a scientist with an ego, or a scientist looking for funding.
Sahara forest to Sahara desert in a microsecond.
If you want to understand the vagaries of the earth’s climate then serious geologists are the ones to listen to...not Al Gore class frauds and poseurs.
So. We ARE all going to die...??
;o]
‘Face
Shoemaker–Levy 9, perhaps, but that was from some distance.
Yes. Every one of us.
Of something.
Eventually.
In the summer of, hmm, 2002, a coworker who was a little spacey most of the time was staring at a spot in the sky. He said to me, "is that a -- shooting star?" I looked up and saw an incoming piece of space junk large enough to make out more than just a nighttime streak. The body was tumbling and coming apart, really interesting, and I kept watching it until the local trees blocked it out. This was in broad daylight. Never saw anything on the news about it, so my guess is, it was shaken to pieces and was probably nothing but pebbles by the time all the remaining mass hit the ground in multiple places.
Buuuut, you're right, quite a correct quibble.
Thank God for Jupiter.
(Punny, no?)
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