Asteroid dust triggered a 15-year winter that killed the dinosaurs, researchers find

Shawn Knight

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The big picture: A massive asteroid slammed into Earth roughly 66 million years ago, triggering a cataclysmic event that wiped out roughly 75 percent of all life on the planet. Now, researchers have a new theory on exactly how the impact altered Earth's history and led to the extinction of the dinosaurs.

Scientists have long believed that sulfur from the impact, or perhaps soot generated from global wildfires triggered by the hit, lingered in the air for years. The resulting dark winter "totally shut down photosynthesis" in plants and lowered global temperatures by as much as 15 degrees Celsius.

Newly published research on the subject, however, reached the same conclusion but took a different route to get there. It is now believed that dust from the impact, not sulfur or soot, primarily led to the dark winter.

The researchers point to dust particles found nearly 1,900 miles away from the suspected Chicxulub impact zone to support their theory. The particles, which measured 0.8 to 8.0 micrometers and were found at the Tanis fossil site in North Dakota, would have been the perfect size to linger in the atmosphere for up to 15 years, and are dated to directly after the asteroid stuck.

The team entered the new data into current-day climate models and now suspect dust played a much larger role in the extinction event. They estimate that 75 percent of the material that was stirred up was dust, 24 percent was sulfur, and just one percent was soot from wildfires. Either way, the particles lingered in the atmosphere long enough to cause a "catastrophic collapse" of life, said Ozgur Karatekin, a researcher at the Royal Observatory of Belgium and a co-author on the study.

This isn't the first time the dust theory has been floated. In 1980, a team led by father and son scientists Luis and Walter Alvarez came to a similar conclusion about the asteroid impact and resulting dust cloud. Their hypothesis didn't gain a ton of traction until the Chicxulub crater was discovered in the Yucatan Peninsula in the early 90s.

Image credit: Pixabay, bt3gl

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Too bad that theory still doesn’t account for the rapid burial required to create the dino fossils we have today.

Must be nice to do science that is literally all post hoc theorizing. Repeatable experiments to verify theory make it a lot harder for the rest of us.
 
I don't hear of many dino fossils happening as a result of Chicxulub, ie: dated to ~66MYA. In fact that's not something I recall at all so not sure what you're on about.
 
Too bad that theory still doesn’t account for the rapid burial required to create the dino fossils we have today.

Must be nice to do science that is literally all post hoc theorizing. Repeatable experiments to verify theory make it a lot harder for the rest of us.
You do know that dinosaurs roamed the earth for almost 160 Million years before they went extinct. That is a really, really, really, really, really, really, really long time. On top of that, the extinction event was 65 Million year ago. There is nothing "rapid" about that.
 
Too bad that theory still doesn’t account for the rapid burial required to create the dino fossils we have today.

Must be nice to do science that is literally all post hoc theorizing. Repeatable experiments to verify theory make it a lot harder for the rest of us.
Is hundreds of millions of years not enough time? Things like mudslides existed back then too you know. Hell there are tons of bison skulls out in the west USA from the last 10,000 years. Dry environments and swamps are great at preserving things, and those were everywhere in dino days.
I don't hear of many dino fossils happening as a result of Chicxulub, ie: dated to ~66MYA. In fact that's not something I recall at all so not sure what you're on about.
Chicxulub is commonly sited as the most likely cause of dino extinction. How long ago were you in school? they were teaching us that in the late 90s.
 
Is hundreds of millions of years not enough time? Things like mudslides existed back then too you know. Hell there are tons of bison skulls out in the west USA from the last 10,000 years. Dry environments and swamps are great at preserving things, and those were everywhere in dino days.
Well if those examples were the answer there should be a lot more dino bones than bison (given the millions of years vs thousands of years), but there are not. Thus, the quest for the missing piece of the puzzle.
 
Come on even the movie Armageddon in 1997 stated that theory.

"Narrator : This is the Earth, at a time when the dinosaurs roamed a lush and fertile planet.

Narrator : A piece of rock just 6 miles wide changed all that.

Narrator : It hit with the force of 10,000 nuclear weapons. A trillion tons of dirt and rock hurtled into the atmosphere, creating a suffocating blanket of DUST the sun was powerless to penetrate for a thousand years. It happened before...It will happen again. It's just a question of when.
 
Chicxulub is commonly sited as the most likely cause of dino extinction. How long ago were you in school? they were teaching us that in the late 90s.

Please read again, I didn't mention extinction one way or another. The person I was responding to was assuming the Chicxulub impactor extinction event had something to do with making fossils, which it doesn't and nobody claims it does.

Fossil creation only happens under specific conditions which an extinction event does not create, which is the flaw in his reasoning.
 
Well if those examples were the answer there should be a lot more dino bones than bison (given the millions of years vs thousands of years), but there are not. Thus, the quest for the missing piece of the puzzle.

Lol, got some numbers comparing found bison bones to dinosaur bones? Go ahead and tell me about the conditions under which bison and dino bones fossils are created, especially the differences between 2 and 200 million years ago. How familiar are you with the climate and geological variations at the time creating fossilization conditions? How about soil layering and compaction and erosion over a 200,000,000 year time range, as well as uplift, ground deformation, glaciation, volcanic output, etc.

Unsurprisingly a single line fails to generate much interest in alternative dino fossilization ideas.
 
Too bad that theory still doesn’t account for the rapid burial required to create the dino fossils we have today.

Must be nice to do science that is literally all post hoc theorizing. Repeatable experiments to verify theory make it a lot harder for the rest of us.

You do understand that fossils are relatively rare right? Even rarer are complete ones. Most finds are of incomplete skeletons. Sometimes nothing more than a femur or jaw bone. As others have stated flash floods, avalanches, etc. over 160 million years can more than account for how many we've found so far.
 
Too bad that theory still doesn’t account for the rapid burial required to create the dino fossils we have today.

Must be nice to do science that is literally all post hoc theorizing. Repeatable experiments to verify theory make it a lot harder for the rest of us.

You did read what you wrote before you hit “post” yes.

O wait.
 
Bro, everyone knows a meteor didn't kill all the dinosaurs. It was John Wick. A T-rex ate his dog.
 
You do understand that fossils are relatively rare right? Even rarer are complete ones. Most finds are of incomplete skeletons. Sometimes nothing more than a femur or jaw bone. As others have stated flash floods, avalanches, etc. over 160 million years can more than account for how many we've found so far.
I am aware of how rare fossils are.
How relatively equally rare they are for animals across different time periods and periods of time - which has yet to be adequately explained by paleontologists. Unless you suggesting that the shorter time periods had a proportional increase in "flash floods, avalanches, etc.", then that explanation doesn't explain it either.
 
I am aware of how rare fossils are.
How relatively equally rare they are for animals across different time periods and periods of time - which has yet to be adequately explained by paleontologists. Unless you suggesting that the shorter time periods had a proportional increase in "flash floods, avalanches, etc.", then that explanation doesn't explain it either.
Okay, re-read what you just said. You said that they're equally rare over different time periods. Right? That's what you wrote. And then you state that I'm suggesting that shorter time periods had an increase in events that could possibly cause fossiles? WTF?!?

You have to be trolling because that makes absolutely zero sense. We're talking about vast periods of time here, millions of years. Add to that the tendency for minerals to be recycled by geological processes such as weathering or plate tectonics, and only certain areas will be stable enough for fossils to survive. That's one of the reasons that they're both rare and tend to be found in clusters.

And yes they should be relatively equal between time periods, when you consider that there's less fossils created after a certain period, it takes at least 10,000 years before they're classified as fossils. But there's also less geological forces destroying them as well, so it should pretty much even out IMHO.

As for your self proclaimed status as a "scientist", it really doesn't have any standing in an on-line forum. For all I know you're 12, your posting logic seems to suggest it. So with that and the level of posting you've made, my only conclusion is you're trolling. So you can post anything further you wish, I'm not going to feed you. No matter how much you want to argue over really poorly thought out arguments, this is the last time I'll engage with you.

So long and thanks for all the fish...
 
Okay, re-read what you just said. You said that they're equally rare over different time periods. Right? That's what you wrote. And then you state that I'm suggesting that shorter time periods had an increase in events that could possibly cause fossiles? WTF?!?

You have to be trolling because that makes absolutely zero sense. We're talking about vast periods of time here, millions of years. Add to that the tendency for minerals to be recycled by geological processes such as weathering or plate tectonics, and only certain areas will be stable enough for fossils to survive. That's one of the reasons that they're both rare and tend to be found in clusters.

And yes they should be relatively equal between time periods, when you consider that there's less fossils created after a certain period, it takes at least 10,000 years before they're classified as fossils. But there's also less geological forces destroying them as well, so it should pretty much even out IMHO.

As for your self proclaimed status as a "scientist", it really doesn't have any standing in an on-line forum. For all I know you're 12, your posting logic seems to suggest it. So with that and the level of posting you've made, my only conclusion is you're trolling. So you can post anything further you wish, I'm not going to feed you. No matter how much you want to argue over really poorly thought out arguments, this is the last time I'll engage with you.

So long and thanks for all the fish...
Well you still are missing my argument so I'm not going to restate it a third time. Good talk.
 
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