8 ms·

Ice

273 points by pshaw 6y ago

peteretep 6y ago
> It’s unlikely we could prevent such a collapse from occurring, but by anticipating such an event we may be able to save many lives and livelihoods. Not while there’s so much political power to be had through climate change denial, which, I hope we start to treat with the same complete disgust and moral outrage as we treat Holocaust denial.
- seibelj 6y ago
  What also disgusts me are so-called environmentalists that stick their fingers in their ears and ignore reality. For example solar panels and wind farms aren’t going to get our carbon footprint to zero anytime soon - the technology is decades (maybe?) away to store and transmit this power to non-sunny and non-windy areas, and there is no solution for their intermittent power generation during extended periods of low-wind and cloud (or smoke!) cover. The only rational solution is nuclear power! But try putting that to a vote and see where it gets you. Additionally scientists should be looking at bandaids to extract carbon from the air or reflect sun back to space. Malthusians who wish everyone just uses less power are both irrational and immoral. We should be trying to give every person on earth as much power as possible with the least damage to the environment. Modern society needs power.
  - tashi 6y ago
    Why is this an important argument to have now? As long as millions of voters believe the climate isn't changing or don't understand what kind of damage it's going to do, it seems like focusing on these details just adds to the noise.
    - seibelj 6y ago
      No, because the organized environmental movement is convincing us that putting solar panels on our roofs and driving electric cars are somehow going to save the planet, when they won’t even make a tiny dent! Yet we are all expected to pay out the ass in tax rebates to subsidize these boondoggles. I support rational and efficient energy policies, but our current system is bonkers! For example I got a 25% tax rebate replacing my skylight because it has a tiny solar-powered shade on it. The installer even joked to me that the $4k off the light was a scam! How is this helping the climate again?
      - zaroth 6y ago
        Your skylight anecdote aside, the EV rebates are about subsidizing the creation of an entirely new trillion dollar industry around batteries and electrification. They are about moving up the “manufacturing learning curve” at an accelerated rate on this new technology. And they are also about geopolitically moving away from oil. The relatively meager environmental gains along the way are dwarfed by the larger environmental gain that start really compounding after 15-20 years of investment on this particular technological path and energy policy.
      - Fellshard 6y ago
        Signaling alone is a powerful motivator.
      - mavhc 6y ago
        It will make a tiny dent, and did you think this wasn't going to be expensive?
    - throwaway2048 6y ago
      Thats the goal
  - ndespres 6y ago
    I think you're final paragraph is contradictory. I think the environmental impact of our limitless energy consumption so far is clear. Reducing consumption is the only way to reduce further impact. Modern society uses a lot of unnecessary energy in part because someone gets to make a lot of money now and leave this life before the consequences of unfettered destruction come due.
    - seibelj 6y ago
      You are using vastly more energy than a hunter gatherer did, or someone in the Middle Ages. Where do we draw the line? Isn’t it unfair that you use a computer, air conditioning, TV, etc. when you don’t really need it? And what happens when every other human uses as much power as Western citizens do? It’s quite hypocritical to say it’s ok for you, but not for the rest of the world. I say, we should have as much power as possible, generated as cleanly as possible, and the lowest possible cost. This is how we move society forwards.
      - zaroth 6y ago
        US CO2 emissions have been falling for more than a decade and are at 1990s levels, and will continue to fall. Energy is the lifeblood of civilization. Reducing the cost of energy, and widespread availability of energy is responsible for saving perhaps a billion lives and bettering nearly 10 billion lives over the last century (that is to say, basically all of them). The idea of putting a stranglehold on worldwide energy production or access is abhorrent when you look at the on-the-ground effects that such a policy would actually have on people’s lives. As you rightly point out, the most marginalized people worst of all. Even if we could somehow stop industry from emitting even a gram of CO2 on 1/1/2021 going forward, the climate models still predict their 10 meter sea level rise just given the current greenhouse levels persisting. The only answer is technological, and in my opinion it’s frankly not even going to be that complicated of a problem given the resources and technology available circa 2050 to deal with it. Franky, solar shades seemed a lot harder of an ask pre-Starship. Looking forward to seeing SN8 reach for 60km in the near future.
  - rtpg 6y ago
    "solar and wind aren't net positives" is a pretty tired argument. We're already in a second decade of both of these technologies being cost efficient and useful! Perhaps it's not going to cover 100% of things. But it's a thing you can be doing and it doesn't make things worse. Meanwhile even with the relatively low usage of nuclear there are two regions of the world that used to be populated with people that now are abandoned.
code_duck 6y ago
While I was reading this article, I was redirected to a spurious "Update Adobe Flash" page.
- muglug 6y ago
  Ditto. Those scammers really need to find a new target. Flash is so 2006.
  - xmprt 6y ago
    I think these scammers know exactly who their target is.
- nickhalfasleep 6y ago
  I went back, got a "Your AntiVirus is out of date" ad next.
  - deleted 6y ago
    [deleted]
  - teknopaul 6y ago
    hmm, who runs the ads on WordPress.com? Would that be Oracle's ad network?
- SAI_Peregrinus 6y ago
  I see people post about ads and I always wonder why it isn't common to consider ad blockers as the first line of defense against malware? Unlike antivirus they also actually make your system faster, since you don't have to use bandwidth & cpu downloading & running ads. You could selectively disable blocking of ads from networks you trust, or on sites you trust, if you want to see ads/support sites that don't have other monetization.
throwaway5752 6y ago
https://www.scientificamerican.com/article/no-there-wasnt-an-advanced-civilization-12-000-years-ago/ https://www.scientificamerican.com/article/no-there-wasnt-an... should accompany this. The whole younger Dryas advanced civilization think could have been avoided entirely and the point about ice melt rates would have been fine.
- ncmncm 6y ago
  That SA article has been overtaken by events. We still don't have any evidence of early, drowned civilizations, but the comet strike now seems to be responsible for extinctions in both South America and Africa. As an aside, you don't need a crater. Multiple airbursts over a wide area, Tunguska style, provide plenty of devastation. You might be able to believe in mass extinctions caused by newly arrived humans in South America, but explaining the African ones the same way ought to get you funny looks. The more you think about that, the less plausible human responsibility for the American extinctions becomes.
  - shawnb576 6y ago
    Do you have citations for this?
    - ncmncm 6y ago
      A very good references list is at the end of "Deadly Voyager", by James Lawrence Powell (available free on Kindle to Prime subscribers), and is reproduced at http://deadlyvoyager.net/References/ http://deadlyvoyager.net/References/
  - robbiep 6y ago
    Interestingly I was reading about this this morning whilst reviewing my old crackpot hero Graham Hancock (reading fingerprints of the gods at a young age had me fascinated about this mythical ancient civilisation for which exceptional claims are made but very little evidence). This is a great rebuttal of the whole YDIH. Specifically regarding the possibility of air bursts, (0) says this: The firestorm began in 2007 when Richard Firestone and numerous colleagues proposed that it was a comet strike of “multiple ET [extraterrestrial] airbursts along with surface impacts” that occurred at 12,900 years ago that initiated the YD.”23 The paper was full of impressive evidence gathered from 10 sites where a carbon-rich layer (referred to as the “black mat”) marked what they claimed was the end of the Clovis culture in North America: “The in situ bones of extinct Pleistocene megafaunas, along with Clovis tool assemblages, occur below this black layer but not within or above it.” They reported that sediments directly below the black mat were enriched in magnetic grains, iridium, magnetic microspherules, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds and fullerenes containing extraterrestrial helium. They explained that the soot, charcoal, spherules, etc. were the result of extensive and intense forest fires initiated by the airbursts. Melting of the Laurentide Ice Sheet would have dumped copious quantities of melt water into the Atlantic, thereby disrupting the density currents and bringing on the cooling. Over the years, however, support for the YDIH has been undermined. Nearly every aspect of the original evidence has been challenged by a host of scientists in various fields. Only one of the indicators, iridium, has been commonly used as an impact marker, and the iridium data have not always been reproducible. The iridium concentrations can also be explained by terrestrial origins.24, 25 Nor do nanodiamonds require extraterrestrial events. The absence of any impact craters at the beginning of the YD worldwide is the most disconcerting evidence against YDIH, as is the lack of control for the age of sediments/black mat at or near the YD boundary. Elsewhere it remarks that even should air bursts be the case, from a massive comet breaking up or multiple comets breaking up, there still must be corresponding craters of the size of Meteor crater to correspond to the scale of the proposed devestation In addition to these arguments against the YDIH, it is difficult to imagine how an airburst/impact could annihilate the North American mammal megafauna and Clovis culture and initiate huge wild fires, without leaving any evidence in the way of massive flooding or impact features. Vance Holliday and his colleagues argue that “no physical mechanism is known to produce an airburst that would affect the entire continent.”27 They also point out that any comet strike large enough to affect an entire continent would leave a detectable crater even if it struck the ice sheet. To get around this glaring problem, the Firestone group proposed that the comet broke up upon entry into earth’s atmosphere. But according to physicist Mark Boslough and his colleagues,28 that would produce “more than a million Meteor craters” (the size of the crater in central Arizona) based on the comet size postulated by Firestone and his cohorts.29, 30 While the Firestone group claims that the comet strike was responsible for the disappearance of the 37 mammal megafauna genera specifically in North America, extinctions occurred on other continents, most notably South America, where at least 52 mammal genera disappeared. And not all those genera disappeared synchronously at the YD boundary! Instead, megafauna extinctions on continents and islands seem to correlate with the arrival of humans. The thinking goes that these huge megafauna would have had no reason to fear humans, and were probably easy pickings for the newly arriving hunter-gatherers. Scientists have also been a bit incredulous that a comet strike could wipe out all the megafauna as far south as Patagonia, while leaving mammoths alive and well on St. Paul Island, Alaska until 3,700 years ago (0) https://www.skeptic.com/reading_room/defant-analysis-of-hancock-claims-in-magicians-of-the-gods/ https://www.skeptic.com/reading_room/defant-analysis-of-hanc...
waiseristy 6y ago
If you want to learn more about the Missoula floods https://www.youtube.com/watch?v=wJo8m4oKc6k https://www.youtube.com/watch?v=wJo8m4oKc6k https://www.youtube.com/watch?v=i1BFb_uYlFQ https://www.youtube.com/watch?v=i1BFb_uYlFQ https://www.youtube.com/watch?v=w7eqBtc2tv0 https://www.youtube.com/watch?v=w7eqBtc2tv0 And then you can come to your own conclusions on whether or not you believe in the meteor impact theory, rapid destabilization theory, etc. But, I have a feeling the solution is simpler. It only takes one tiny stream of water to make it's way through the glacier and start eroding away at it. If you've seen videos of dams collapsing, they also start from the smallest of trickles which quickly turns into a feedback loop of more erosive power.
- doctoboggan 6y ago
  Another good video: https://youtu.be/YWZgfPGtQEs https://youtu.be/YWZgfPGtQEs
  - incomplete 6y ago
    wtf, people. thanks for the deep rabbit hole i've been stuck in learning about the geology of the region. :)
undersuit 6y ago
I lived in Missoula, MT for over a decade after my father moved us there for his law schooling. I knew vaguely about Glacial Lake Missoula, but seeing the actual effects as I traveled from Missoula to my parents new home in the Tri-cities-WA really hammered home the size of the floods. And then again when I flew into Pasco from Seattle and I saw the cliffs that funneled the floods south. I suspect my geologist father always knew where he was going.
chrisco255 6y ago
This essay mentions the Younger Dryas but what it doesn't mention is that the Younger Dryas was a sudden return to glacial temperatures after the earth had already warmed up at the end of the last glacial period. The magnitude of these swings in both directions are absolutely enormous and occur at much too rapid a speed to be attributable to trace greenhouse gas concentrations. Something else must have caused those swings. Either volcanic and geothermal activity or meteoric activity are the only likely culprits. https://en.m.wikipedia.org/wiki/Younger_Dryas https://en.m.wikipedia.org/wiki/Younger_Dryas There is evidence of Geothermal activity under the Antarctic ice sheet. Why is magma not on the table for glacial melting? See NASA article below: https://www.jpl.nasa.gov/news/news.php?feature=6996 https://www.jpl.nasa.gov/news/news.php?feature=6996 By the way the Antarctic ice sheet is currently at median levels (based on 1981-2010 baseline): https://nsidc.org/data/seaice_index/ https://nsidc.org/data/seaice_index/ The article also mentions 1m of sea level rise before 2100. There is no evidence of sea level rise acceleration. It is averaging 3.3 mm per year since 1993. Assuming there is not a cyclical downtrend in sea level (likely sometime this century, given grand solar minimum odds or chance of a major volcanic event), that would only amount to just under a foot per century of sea level rise. Source: https://climate.nasa.gov/vital-signs/sea-level/ https://climate.nasa.gov/vital-signs/sea-level/
- bosswipe 6y ago
  > Either volcanic and geothermal activity or meteoric activity are the only likely culprits. Another possibility is abrupt changes in the flow of large bodies of waters affecting ocean circulation causing climate changes. One hypotheses is as the glaciers retreated the waters of the Missisppi river switched to flowing out of the St Lawrence river affecting North Atlantic currents.
- deleted 6y ago
  [deleted]
- divbzero 6y ago
  Why is it that the Antarctic ice sheet is currently at median levels while Arctic ice pack has changed so dramatically?
ChrisMarshallNY 6y ago
Cool article. My mother[0] was a geologist, and I was raised in an environment, where she was constantly pointing at rocks and terrain, telling me about how they were formed. I live on Long Island, New York, which is called a “terminal moraine.”[1] I.e. “glacier poop.” When you realize that Long Island is 125 miles long, you can appreciate the size of the glacier that created it. The Ice Age was AWESOME. (0] http://cmarshall.com/miscellaneous/SheilaMarshall.htm http://cmarshall.com/miscellaneous/SheilaMarshall.htm [1] https://en.m.wikipedia.org/wiki/Terminal_moraine https://en.m.wikipedia.org/wiki/Terminal_moraine
sradman 6y ago
> ... a gradual and linear melting rate is not what we should expect to see going forward. This article seems to combine the lost civilization pseudo-science of Randall Carlson and Graham Hancock with the myopia of catastrophic climate change alarmists that ignore paleoclimate evidence. This evidence is captured in the LR04 Benthic Stack data and is fully supported by ice core and other data sources. Modelling the fluid dynamics following the termination of the last glacial maxima is non-trivial but the broad strokes are well understood. The 120 meter change in sea levels during the 100-kyr glacial cycles are associated with predictable ice sheets, post-glacial rebound, glacial lakes, and meltwater pulses. Something similar to Glacial Lake Missoula occurred after each termination. What we should expect to see moving forward is the start of the re-accumulation of glacial ice timed to the Milankovich Cycles. The question is how big a monkey wrench does human forced atmospheric CO2 throw into the established cycles.
- ncmncm 6y ago
  Except nobody knows what actually caused the beginning or ending of an ice age. It is always too easy to think you must know what is relevant, after learning what seems like a lot.
  - sradman 6y ago
    The Marine Isotope Stages (MIS) [1] are based on the empirically derived LR04 Benthic Stack. We don't (yet) know how to model the termination triggers nor the precise magnitude of each glacial cycle but what this means in practice is that we don't understand why the system transitioned from 41 kyr cycles to 100 kyr cycles; the regular glacial cycles themselves are very real. The "nobody knows" claim applies no more to the LR04/MIS evidence than it does to tectonic plate evidence. This is well established science not an arena to practice Hayekian "fatal conceit" dismissals. [1] https://en.wikipedia.org/wiki/Marine_isotope_stage https://en.wikipedia.org/wiki/Marine_isotope_stage
    - ncmncm 6y ago
      "Nobody knows what makes the sun rise." "We have excellent records of its reliable daily rise, going back centuries." But sunrise is caused by rotation of a spheroid planet, in no way implied by those records.
deleted 6y ago
[deleted]
GregoryVPerry 6y ago
What is this hunk of bullshit
wffurr 6y ago
The author seems to think we are "safe" from impact events, but that seems awfully glib and based more on pop culture takes like movies than facts. Our track record for noticing near Earth objects is pretty poor and largely due to amateur astronomers. I don't think there is any consensus on what sort of space mission we could mount to divert one either. We are a long way from "planetary defenses have never been stronger": https://youtu.be/QkpP5Nz7zuY?t=34 https://youtu.be/QkpP5Nz7zuY?t=34
- MichaelZuo 6y ago
  Your right, a lot of the speculation in the article uses unjustified assumptions to move the reader on to the final point. When a sensible analysis would probably categorize a impact or air burst similar to the Tunguska event as one of the likeliest, if not the likeliest, cause.
- ncmncm 6y ago
  It is technically true that planetary defenses have never been stronger. It is exactly, equally true that they have never been weaker. 0<=0<=0
robotsquidward 6y ago
If you like this article, checkout this feature on The Scablands in ArsTechnica from a few years ago, a fun read: https://arstechnica.com/science/2014/10/the-scablands-a-scarred-landscape-as-strange-as-fiction/ https://arstechnica.com/science/2014/10/the-scablands-a-scar...
- Raphmedia 6y ago
  Note for everyone else who, like me, isn't used to using this website: There is a page switcher at the bottom of the article where you need to manually go to the next page to read more.
Ccecil 6y ago
I live on the edge of this area. Coeur d'Alene, ID is at the mid upper right in that map...Spokane/Cd'A are the cities you can see by the lakes. Cd'A is at the bottom of what is known as the Purcell trench. It is very clear if you look at the area that this flood happened suddenly. Lots of exposed rimrock, the Rathdrum aquifer is massive and everything out here is riddled with glacial tumbled granite. Lake Pend Orielle is one of the deepest in the nation and at the North side is where the Clark fork "dam" was from the ice. When you look at the mountains where the river comes through they are fairly tall but there is a very noticeable "v" where the river comes through.[1] I would be more willing to believe something destabilized the mountain that was supporting the ice (earthquake? We do get them here). Geologically this event happened not that long ago. Scars are clearly visible pretty much in all of the area if you look close. There is some discussion as well that there are stories of this event in various oral histories of the native people but I think it is still being studied. Sidenote: Lake Pend Orielle was where Farragut naval base was...totally landlocked naval base where they still test sonar to this day. [2] Rumor has it they used to collapse subs in the lake due to how deep it was...but I am not sure how factual that is. [1] http://hugefloods.com/Ice-Age-Floods-2.html http://hugefloods.com/Ice-Age-Floods-2.html Pic here labeled "Clark fork river" shows what I mean...but small picture [2] https://en.wikipedia.org/wiki/Farragut_Naval_Training_Station https://en.wikipedia.org/wiki/Farragut_Naval_Training_Statio...

273 points by pshaw 6y ago

> It’s unlikely we could prevent such a collapse from occurring, but by anticipating such an event we may be able to save many lives and livelihoods. Not while there’s so much political power to be had through climate change denial, which, I hope we start to treat with the same complete disgust and moral outrage as we treat Holocaust denial.

seibelj 6y ago
What also disgusts me are so-called environmentalists that stick their fingers in their ears and ignore reality. For example solar panels and wind farms aren’t going to get our carbon footprint to zero anytime soon - the technology is decades (maybe?) away to store and transmit this power to non-sunny and non-windy areas, and there is no solution for their intermittent power generation during extended periods of low-wind and cloud (or smoke!) cover. The only rational solution is nuclear power! But try putting that to a vote and see where it gets you. Additionally scientists should be looking at bandaids to extract carbon from the air or reflect sun back to space. Malthusians who wish everyone just uses less power are both irrational and immoral. We should be trying to give every person on earth as much power as possible with the least damage to the environment. Modern society needs power.
- tashi 6y ago
  Why is this an important argument to have now? As long as millions of voters believe the climate isn't changing or don't understand what kind of damage it's going to do, it seems like focusing on these details just adds to the noise.
  - seibelj 6y ago
    No, because the organized environmental movement is convincing us that putting solar panels on our roofs and driving electric cars are somehow going to save the planet, when they won’t even make a tiny dent! Yet we are all expected to pay out the ass in tax rebates to subsidize these boondoggles. I support rational and efficient energy policies, but our current system is bonkers! For example I got a 25% tax rebate replacing my skylight because it has a tiny solar-powered shade on it. The installer even joked to me that the $4k off the light was a scam! How is this helping the climate again?
    - zaroth 6y ago
      Your skylight anecdote aside, the EV rebates are about subsidizing the creation of an entirely new trillion dollar industry around batteries and electrification. They are about moving up the “manufacturing learning curve” at an accelerated rate on this new technology. And they are also about geopolitically moving away from oil. The relatively meager environmental gains along the way are dwarfed by the larger environmental gain that start really compounding after 15-20 years of investment on this particular technological path and energy policy.
    - Fellshard 6y ago
      Signaling alone is a powerful motivator.
    - mavhc 6y ago
      It will make a tiny dent, and did you think this wasn't going to be expensive?
  - throwaway2048 6y ago
    Thats the goal
- ndespres 6y ago
  I think you're final paragraph is contradictory. I think the environmental impact of our limitless energy consumption so far is clear. Reducing consumption is the only way to reduce further impact. Modern society uses a lot of unnecessary energy in part because someone gets to make a lot of money now and leave this life before the consequences of unfettered destruction come due.
  - seibelj 6y ago
    You are using vastly more energy than a hunter gatherer did, or someone in the Middle Ages. Where do we draw the line? Isn’t it unfair that you use a computer, air conditioning, TV, etc. when you don’t really need it? And what happens when every other human uses as much power as Western citizens do? It’s quite hypocritical to say it’s ok for you, but not for the rest of the world. I say, we should have as much power as possible, generated as cleanly as possible, and the lowest possible cost. This is how we move society forwards.
    - zaroth 6y ago
      US CO2 emissions have been falling for more than a decade and are at 1990s levels, and will continue to fall. Energy is the lifeblood of civilization. Reducing the cost of energy, and widespread availability of energy is responsible for saving perhaps a billion lives and bettering nearly 10 billion lives over the last century (that is to say, basically all of them). The idea of putting a stranglehold on worldwide energy production or access is abhorrent when you look at the on-the-ground effects that such a policy would actually have on people’s lives. As you rightly point out, the most marginalized people worst of all. Even if we could somehow stop industry from emitting even a gram of CO2 on 1/1/2021 going forward, the climate models still predict their 10 meter sea level rise just given the current greenhouse levels persisting. The only answer is technological, and in my opinion it’s frankly not even going to be that complicated of a problem given the resources and technology available circa 2050 to deal with it. Franky, solar shades seemed a lot harder of an ask pre-Starship. Looking forward to seeing SN8 reach for 60km in the near future.
- rtpg 6y ago
  "solar and wind aren't net positives" is a pretty tired argument. We're already in a second decade of both of these technologies being cost efficient and useful! Perhaps it's not going to cover 100% of things. But it's a thing you can be doing and it doesn't make things worse. Meanwhile even with the relatively low usage of nuclear there are two regions of the world that used to be populated with people that now are abandoned.

code_duck 6y ago

While I was reading this article, I was redirected to a spurious "Update Adobe Flash" page.

muglug 6y ago
Ditto. Those scammers really need to find a new target. Flash is so 2006.
- xmprt 6y ago
  I think these scammers know exactly who their target is.
nickhalfasleep 6y ago
I went back, got a "Your AntiVirus is out of date" ad next.
- deleted 6y ago
  [deleted]
- teknopaul 6y ago
  hmm, who runs the ads on WordPress.com? Would that be Oracle's ad network?
SAI_Peregrinus 6y ago
I see people post about ads and I always wonder why it isn't common to consider ad blockers as the first line of defense against malware? Unlike antivirus they also actually make your system faster, since you don't have to use bandwidth & cpu downloading & running ads. You could selectively disable blocking of ads from networks you trust, or on sites you trust, if you want to see ads/support sites that don't have other monetization.

throwaway5752 6y ago

https://www.scientificamerican.com/article/no-there-wasnt-an-advanced-civilization-12-000-years-ago/ https://www.scientificamerican.com/article/no-there-wasnt-an... should accompany this. The whole younger Dryas advanced civilization think could have been avoided entirely and the point about ice melt rates would have been fine.

ncmncm 6y ago
That SA article has been overtaken by events. We still don't have any evidence of early, drowned civilizations, but the comet strike now seems to be responsible for extinctions in both South America and Africa. As an aside, you don't need a crater. Multiple airbursts over a wide area, Tunguska style, provide plenty of devastation. You might be able to believe in mass extinctions caused by newly arrived humans in South America, but explaining the African ones the same way ought to get you funny looks. The more you think about that, the less plausible human responsibility for the American extinctions becomes.
- shawnb576 6y ago
  Do you have citations for this?
  - ncmncm 6y ago
    A very good references list is at the end of "Deadly Voyager", by James Lawrence Powell (available free on Kindle to Prime subscribers), and is reproduced at http://deadlyvoyager.net/References/ http://deadlyvoyager.net/References/
- robbiep 6y ago
  Interestingly I was reading about this this morning whilst reviewing my old crackpot hero Graham Hancock (reading fingerprints of the gods at a young age had me fascinated about this mythical ancient civilisation for which exceptional claims are made but very little evidence). This is a great rebuttal of the whole YDIH. Specifically regarding the possibility of air bursts, (0) says this: The firestorm began in 2007 when Richard Firestone and numerous colleagues proposed that it was a comet strike of “multiple ET [extraterrestrial] airbursts along with surface impacts” that occurred at 12,900 years ago that initiated the YD.”23 The paper was full of impressive evidence gathered from 10 sites where a carbon-rich layer (referred to as the “black mat”) marked what they claimed was the end of the Clovis culture in North America: “The in situ bones of extinct Pleistocene megafaunas, along with Clovis tool assemblages, occur below this black layer but not within or above it.” They reported that sediments directly below the black mat were enriched in magnetic grains, iridium, magnetic microspherules, charcoal, soot, carbon spherules, glass-like carbon containing nanodiamonds and fullerenes containing extraterrestrial helium. They explained that the soot, charcoal, spherules, etc. were the result of extensive and intense forest fires initiated by the airbursts. Melting of the Laurentide Ice Sheet would have dumped copious quantities of melt water into the Atlantic, thereby disrupting the density currents and bringing on the cooling. Over the years, however, support for the YDIH has been undermined. Nearly every aspect of the original evidence has been challenged by a host of scientists in various fields. Only one of the indicators, iridium, has been commonly used as an impact marker, and the iridium data have not always been reproducible. The iridium concentrations can also be explained by terrestrial origins.24, 25 Nor do nanodiamonds require extraterrestrial events. The absence of any impact craters at the beginning of the YD worldwide is the most disconcerting evidence against YDIH, as is the lack of control for the age of sediments/black mat at or near the YD boundary. Elsewhere it remarks that even should air bursts be the case, from a massive comet breaking up or multiple comets breaking up, there still must be corresponding craters of the size of Meteor crater to correspond to the scale of the proposed devestation In addition to these arguments against the YDIH, it is difficult to imagine how an airburst/impact could annihilate the North American mammal megafauna and Clovis culture and initiate huge wild fires, without leaving any evidence in the way of massive flooding or impact features. Vance Holliday and his colleagues argue that “no physical mechanism is known to produce an airburst that would affect the entire continent.”27 They also point out that any comet strike large enough to affect an entire continent would leave a detectable crater even if it struck the ice sheet. To get around this glaring problem, the Firestone group proposed that the comet broke up upon entry into earth’s atmosphere. But according to physicist Mark Boslough and his colleagues,28 that would produce “more than a million Meteor craters” (the size of the crater in central Arizona) based on the comet size postulated by Firestone and his cohorts.29, 30 While the Firestone group claims that the comet strike was responsible for the disappearance of the 37 mammal megafauna genera specifically in North America, extinctions occurred on other continents, most notably South America, where at least 52 mammal genera disappeared. And not all those genera disappeared synchronously at the YD boundary! Instead, megafauna extinctions on continents and islands seem to correlate with the arrival of humans. The thinking goes that these huge megafauna would have had no reason to fear humans, and were probably easy pickings for the newly arriving hunter-gatherers. Scientists have also been a bit incredulous that a comet strike could wipe out all the megafauna as far south as Patagonia, while leaving mammoths alive and well on St. Paul Island, Alaska until 3,700 years ago (0) https://www.skeptic.com/reading_room/defant-analysis-of-hancock-claims-in-magicians-of-the-gods/ https://www.skeptic.com/reading_room/defant-analysis-of-hanc...

waiseristy 6y ago

If you want to learn more about the Missoula floods https://www.youtube.com/watch?v=wJo8m4oKc6k https://www.youtube.com/watch?v=wJo8m4oKc6k https://www.youtube.com/watch?v=i1BFb_uYlFQ https://www.youtube.com/watch?v=i1BFb_uYlFQ https://www.youtube.com/watch?v=w7eqBtc2tv0 https://www.youtube.com/watch?v=w7eqBtc2tv0 And then you can come to your own conclusions on whether or not you believe in the meteor impact theory, rapid destabilization theory, etc. But, I have a feeling the solution is simpler. It only takes one tiny stream of water to make it's way through the glacier and start eroding away at it. If you've seen videos of dams collapsing, they also start from the smallest of trickles which quickly turns into a feedback loop of more erosive power.

doctoboggan 6y ago
Another good video: https://youtu.be/YWZgfPGtQEs https://youtu.be/YWZgfPGtQEs
- incomplete 6y ago
  wtf, people. thanks for the deep rabbit hole i've been stuck in learning about the geology of the region. :)

undersuit 6y ago

I lived in Missoula, MT for over a decade after my father moved us there for his law schooling. I knew vaguely about Glacial Lake Missoula, but seeing the actual effects as I traveled from Missoula to my parents new home in the Tri-cities-WA really hammered home the size of the floods. And then again when I flew into Pasco from Seattle and I saw the cliffs that funneled the floods south. I suspect my geologist father always knew where he was going.

chrisco255 6y ago

This essay mentions the Younger Dryas but what it doesn't mention is that the Younger Dryas was a sudden return to glacial temperatures after the earth had already warmed up at the end of the last glacial period. The magnitude of these swings in both directions are absolutely enormous and occur at much too rapid a speed to be attributable to trace greenhouse gas concentrations. Something else must have caused those swings. Either volcanic and geothermal activity or meteoric activity are the only likely culprits. https://en.m.wikipedia.org/wiki/Younger_Dryas https://en.m.wikipedia.org/wiki/Younger_Dryas There is evidence of Geothermal activity under the Antarctic ice sheet. Why is magma not on the table for glacial melting? See NASA article below: https://www.jpl.nasa.gov/news/news.php?feature=6996 https://www.jpl.nasa.gov/news/news.php?feature=6996 By the way the Antarctic ice sheet is currently at median levels (based on 1981-2010 baseline): https://nsidc.org/data/seaice_index/ https://nsidc.org/data/seaice_index/ The article also mentions 1m of sea level rise before 2100. There is no evidence of sea level rise acceleration. It is averaging 3.3 mm per year since 1993. Assuming there is not a cyclical downtrend in sea level (likely sometime this century, given grand solar minimum odds or chance of a major volcanic event), that would only amount to just under a foot per century of sea level rise. Source: https://climate.nasa.gov/vital-signs/sea-level/ https://climate.nasa.gov/vital-signs/sea-level/

bosswipe 6y ago
> Either volcanic and geothermal activity or meteoric activity are the only likely culprits. Another possibility is abrupt changes in the flow of large bodies of waters affecting ocean circulation causing climate changes. One hypotheses is as the glaciers retreated the waters of the Missisppi river switched to flowing out of the St Lawrence river affecting North Atlantic currents.
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divbzero 6y ago
Why is it that the Antarctic ice sheet is currently at median levels while Arctic ice pack has changed so dramatically?

ChrisMarshallNY 6y ago

Cool article. My mother[0] was a geologist, and I was raised in an environment, where she was constantly pointing at rocks and terrain, telling me about how they were formed. I live on Long Island, New York, which is called a “terminal moraine.”[1] I.e. “glacier poop.” When you realize that Long Island is 125 miles long, you can appreciate the size of the glacier that created it. The Ice Age was AWESOME. (0] http://cmarshall.com/miscellaneous/SheilaMarshall.htm http://cmarshall.com/miscellaneous/SheilaMarshall.htm [1] https://en.m.wikipedia.org/wiki/Terminal_moraine https://en.m.wikipedia.org/wiki/Terminal_moraine

sradman 6y ago

> ... a gradual and linear melting rate is not what we should expect to see going forward. This article seems to combine the lost civilization pseudo-science of Randall Carlson and Graham Hancock with the myopia of catastrophic climate change alarmists that ignore paleoclimate evidence. This evidence is captured in the LR04 Benthic Stack data and is fully supported by ice core and other data sources. Modelling the fluid dynamics following the termination of the last glacial maxima is non-trivial but the broad strokes are well understood. The 120 meter change in sea levels during the 100-kyr glacial cycles are associated with predictable ice sheets, post-glacial rebound, glacial lakes, and meltwater pulses. Something similar to Glacial Lake Missoula occurred after each termination. What we should expect to see moving forward is the start of the re-accumulation of glacial ice timed to the Milankovich Cycles. The question is how big a monkey wrench does human forced atmospheric CO2 throw into the established cycles.

ncmncm 6y ago
Except nobody knows what actually caused the beginning or ending of an ice age. It is always too easy to think you must know what is relevant, after learning what seems like a lot.
- sradman 6y ago
  The Marine Isotope Stages (MIS) [1] are based on the empirically derived LR04 Benthic Stack. We don't (yet) know how to model the termination triggers nor the precise magnitude of each glacial cycle but what this means in practice is that we don't understand why the system transitioned from 41 kyr cycles to 100 kyr cycles; the regular glacial cycles themselves are very real. The "nobody knows" claim applies no more to the LR04/MIS evidence than it does to tectonic plate evidence. This is well established science not an arena to practice Hayekian "fatal conceit" dismissals. [1] https://en.wikipedia.org/wiki/Marine_isotope_stage https://en.wikipedia.org/wiki/Marine_isotope_stage
  - ncmncm 6y ago
    "Nobody knows what makes the sun rise." "We have excellent records of its reliable daily rise, going back centuries." But sunrise is caused by rotation of a spheroid planet, in no way implied by those records.

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GregoryVPerry 6y ago

What is this hunk of bullshit

wffurr 6y ago

The author seems to think we are "safe" from impact events, but that seems awfully glib and based more on pop culture takes like movies than facts. Our track record for noticing near Earth objects is pretty poor and largely due to amateur astronomers. I don't think there is any consensus on what sort of space mission we could mount to divert one either. We are a long way from "planetary defenses have never been stronger": https://youtu.be/QkpP5Nz7zuY?t=34 https://youtu.be/QkpP5Nz7zuY?t=34

MichaelZuo 6y ago
Your right, a lot of the speculation in the article uses unjustified assumptions to move the reader on to the final point. When a sensible analysis would probably categorize a impact or air burst similar to the Tunguska event as one of the likeliest, if not the likeliest, cause.
ncmncm 6y ago
It is technically true that planetary defenses have never been stronger. It is exactly, equally true that they have never been weaker. 0<=0<=0

robotsquidward 6y ago

If you like this article, checkout this feature on The Scablands in ArsTechnica from a few years ago, a fun read: https://arstechnica.com/science/2014/10/the-scablands-a-scarred-landscape-as-strange-as-fiction/ https://arstechnica.com/science/2014/10/the-scablands-a-scar...

Raphmedia 6y ago
Note for everyone else who, like me, isn't used to using this website: There is a page switcher at the bottom of the article where you need to manually go to the next page to read more.

Ccecil 6y ago

I live on the edge of this area. Coeur d'Alene, ID is at the mid upper right in that map...Spokane/Cd'A are the cities you can see by the lakes. Cd'A is at the bottom of what is known as the Purcell trench. It is very clear if you look at the area that this flood happened suddenly. Lots of exposed rimrock, the Rathdrum aquifer is massive and everything out here is riddled with glacial tumbled granite. Lake Pend Orielle is one of the deepest in the nation and at the North side is where the Clark fork "dam" was from the ice. When you look at the mountains where the river comes through they are fairly tall but there is a very noticeable "v" where the river comes through.[1] I would be more willing to believe something destabilized the mountain that was supporting the ice (earthquake? We do get them here). Geologically this event happened not that long ago. Scars are clearly visible pretty much in all of the area if you look close. There is some discussion as well that there are stories of this event in various oral histories of the native people but I think it is still being studied. Sidenote: Lake Pend Orielle was where Farragut naval base was...totally landlocked naval base where they still test sonar to this day. [2] Rumor has it they used to collapse subs in the lake due to how deep it was...but I am not sure how factual that is. [1] http://hugefloods.com/Ice-Age-Floods-2.html http://hugefloods.com/Ice-Age-Floods-2.html Pic here labeled "Clark fork river" shows what I mean...but small picture [2] https://en.wikipedia.org/wiki/Farragut_Naval_Training_Station https://en.wikipedia.org/wiki/Farragut_Naval_Training_Statio...