The Last Time the Globe Warmed

[@unvergebeneid]

What's important to keep in mind is that a quantitative difference in the rate of change can mean a qualitative difference in the effect of that change. E.g. if the change is slow enough for a species to adapt, it adapts. If it's faster than it can adapt, the species is gone. Which in turn might cause other species to go extinct, even if they could've otherwise adapted.

[@vampyricon7026]

+

[@CarFreeSegnitz]

Penny Lane Mostly agree... except for the circular adaptation reasoning. Adaptation is adaptation... extinction is extinction. Going extinct because another species went extinct is a case of not adapting to change. Saying a species would not have gone extinct if it weren't for the extinction of another species is purely hypothetical. The result is still the same... the co-dependent species is still extinct for lack of not adapting to the extinction of the other species.

[@unvergebeneid]

Lenard Segnitz, since species extinction is kind of a stochastic process, I still think my way of phrasing it makes sense. And of course it's hypothetical in retrospect or in a specific case but that's not what I'm talking about here.

[@unvergebeneid]

Joseph Burchanowski, sounds like a bold claim tbh. Much of what I'm implicitly referring to in my original comment is from this concept: www.nature.com/articles/nature08649 There are lots of concrete velocities of adaptation that can be determined for species so how does your statement fit into this?

[@unvergebeneid]

Well, migration capacity is one form of adaptation really. But the idea of climate change having a velocity is more generalizable than that. Amongst other things, it describes the ways in which the location of a species' habitat affects its ability to maintain its population. Add to that how fast it can adapt to changing temperatures or habitats (i.e. when it can't physically move fast enough or has nowhere to go) and how fragmented its habitat is (often also because of humans, preventing a species from physically moving) and you get a pretty good idea how non-linear the effect of different speeds of climate change can be, which was my original point.

[@firstnamelastname2298]

I live in Siberia and I want my rain forests back NOW! :)

[@gphilipc2031]

Poof ...here's a burst of methane.

[@firstnamelastname2298]

@@gphilipc2031 viva la methane hydrate :)

[@helengarrett6378]

Yuriy, I want them back for you too. I am happiest in green places among trees, ferns and among wild flowers. I do not get to experience those things enough now as I live in an urban environment and am elderly. But you should have all of it to lift your heart in joy.

[@bobleclair5665]

OK

[@nickiminajfan2327]

Did it rain vodka

[@oldie4210]

I have a friend who was stationed in the high artic in the early 60's with the military. He recalled petrified tree stumps with roots 3 to 4 feet around, under neath a glacier.

[@thetechnicanwithaheart1682]

Yes actually I want to mention to you and the entire Community here my study on at the anthroprogenic climate change including paleo climatology. The national deep Core Ocean lab which is a research Lab at 4. Of a few years was on a large Expedition. The expedition was to drill deep core samples and store those samples on the ship. The Deep core samples would reach depths of the rock-based ocean. Thousands of samples we're drilled and brought onto land in the United States for storage and examination. They recorded carbon levels at the radiocarbon dating point of 55 million years ago that a mass extinction had occurred on Earth. The source of the mass extinction with carbon emissions or carbon-13 isotope that is typically released during a volcanic eruption. They started to measure the period in time how far back these carbon emissions have started it lasted between 5 to 10,000 years. The total Corporation of the Supreme Court high temperature planet Earth over 15 million years. So planet Earth have been plunged into a mass extinction CO2 traps enormous amount of heat energy. But Jared is five to ten thousand time. Of increasing carbon emissions plant life and invertebrate like alligators had time to migrate into the Arctic. The ancient tree for petrified tree that you saw was most likely Left Behind from the paleocene-eocene error 55 million years ago. The rest of the planet most likely cooked kill all tropical and other species on Earth. It's too bad your friend had samples of that petrified wood it would be fascinating to radiocarbon date that would.

[@oldie4210]

@@thetechnicanwithaheart1682 Dwayne died a few years back and I do not know what happened to his personal goods. He did not show me any petrified wood. I remember though he wondered if the earth could of rotated its axis. I believe his story as he was a farmer with no education greater than high school and no aspersions than to be a farmer. Thanks for your info, I appreciate it.

[@electrictroy2010]

The earth has never rotated on its axis, but it has spent 70% of its existence in a tropical state (no ice on poles)

[@izzzzzz6]

Interesting but was he a scientist? Is it possible he mistook basalt columns or other mineral formations for tree stumps. I'm not doubting what he saw just curious as to how this was backed up. Are there any videos on similar petrified stumps in the artic?

[@frankmartin8471]

During the Eemian period some 130,000 years ago (also called the penultimate interglacial period), it was quite warm, sea levels were about 30 feet higher than they are today, and forests were growing north of the Arctic Circle. The earth has gone through some dramatic temperature changes, even in the last 200,000 years or so. We're going to face some challenges adapting to dramatic changes, whatever they may be.

[@Anonymous-nn4sk]

Imagine how many plant and animal species in the arctic went extinct during the cooling after PETM but sea animals may have thrived due to the cooling?

[@onlythewise1]

or died during the ice age which happened a thousand times on earth

[@reuireuiop0]

Cooling after PETM was quite a bit slower, and it didn't last, the Eocene actually had a climate optimum that lasted very much longer, millions of years. That warm period has an enormous effect on mammal evolution, like early horse evolution, the stem fathers of big cats and other predators, and elephant etc etc evolving. Time scales are totally different - carbon and temp rise today only take a couple 100s years, while the onset of petm took at least 20000 and likely longer (equal to the period since last glacial maximum), while the Eocene optimum slowly rose of 100ks of years - that's about as long as all of the recent ice ages, 2 million plus years. So you're talking completely different time sets. If you make each year last a second, current climate change takes a few _minutes_ , petm onset 5 and half _hours_, Eocene optimum over a _week_ Eocene allows complete family branches to evolve, PETM would allow opportist species to adapt, others would be reduced to patches. What will happen once climate change turns into total disturbance, anyone's guess. It's not even halfway through the starting phase, yet.

[@JM-bl3ih]

If only there was an organism on earth that consumed excess CO2 and let put oxygen. We could put these things everywhere. 🤔🤔🤔

[@rihanix9646]

Who knows if eventually it will emerge, knowing evolution, maybe there is a bacteria somewhere that has to deal with this a lot and maybe it's descendants will develop this ability

[@josepeixoto3384]

trees and plants do it,not everyone gets it..

[@rotopope]

@@josepeixoto3384 Have you patented this "Tree" device yet? I hear Richard Branson is offering a prize...

[@Owlbearwolf2]

Deforestation. And actually, the 30% rise in CO2 ppm has affected plants. They're generally growing faster, but less nutrient dense, for the same reason as if you ate more sugar and less protein.

[@gaenorharris-obrien9934]

LOL

[@TenThumbsProductions]

Basic cable news should be swapped for Eons, that would be fantastic.

[@lemonvariable72]

BUT THEN HOW WOULD WE FIND OUT ABOUT STORMY DANIELS?

[@sethtenrec6476]

They need to let this guy talk continuously instead of cutting him in every 5 seconds with another explosive sentence. This is interesting subject matter but horribly presented.

[@brianmessemer2973]

Should I give this comment two thumbs up, or ten thumbs up? Either way, agreed.

[@RockbandDrummer321]

Cmon man we cant have the general populas getting more learnt 😉

[@MikeJones-rk1un]

Bill Clinton gets rich behaving like a lech. Any normal standards would sterilize that guy with a hatchet.

[@davidhobbs5679]

Australia's inland sea would be an interesting topic. Especially how it slowly dries up and the effect it had on climate.

[@vallonskyles1906]

Yeah it would!

[@KneeJerkReactions13]

Or Canada's. I work at a gravel pit and one truck driver showed me picsof sea turtle fossils. Why do you reckon we have so much oil..

[@bellrugby03]

We still know so little, I lived in central Australia and found an old disused mine that had sea shells, they weren't fossilised, there's even a miniature version of our giant mangrove crabs that survive today in small freshwater rivers in the outback..🤔

[@johnwang9914]

And whether these shallow inland seas could return as oceans rise and ground subsides from thawing permafrost in say Canada.

[@adampickard9880]

+

[@RICKONORATO]

We always hear about how balmy it was in the Arctic during this time, but then what was life like at the equator during this period? Deserts? Unlivable and devoid of life? More tropical rainforests? I'd like to know what the rest of the planet was experiencing when temperatures were so much higher...

[@RICKONORATO]

@@vladamirkb1 I suppose that's true!

[@berniefynn6623]

The only reason the viking got their long boats to America was because of the warming, calmed the seas.

[@matt54321100]

It’s already hellishly hot around the equator and already reaches beyond the heat tolerance of humans. I’d hate to know how bad it would be in those times

[@mattnsac]

@@matt54321100 Humans wouldnt live there. Few people live in the Sahara or in Death Valley for that matter. Conversely, a few degrees colder and the population of England would be closer to Alaska as it would be frozen for all but a few months of the year. Humans will thrive in a warmer climate, the question is what will NOT thrive as a result?

[@wlenore8071]

Deserts or underwater is my guess…hot as hell or flooded by polar ice caps making sea levels higher. Keep in mind that the continents may have been different due to plate tectonics

[@ShirinRose]

I wonder what it was like in the rainforests at the poles during the long night of winter.

[@Kram1032]

That really is an interesting question. Wake/Sleep schedules must have been extremely messed up by our standards. All animals would have had to be reasonable at navigating both day and night or else just hide and sleep through most of one or the other, right? And how did plants deal with several months worth of not just less but almost no light followed by months of no night?

[@jessenoell2154]

Fir, spruce trees deal with it today, don't they?

[@Kram1032]

That's true to a point. I think there's a zone past which there basically are no trees anymore? Both in the north and in the south? Although they probably do grow past the polar circles? - We're talking a bit more than 66° up and down. And then a little more on top, because the sun actually reaches farther up and down due to atmospheric light bending. Call it 67°. Apparently the Taiga goes from about 42° - 71°, so a small portion of it will indeed grow well into that area. On the south side, as far as I can tell, the only lands (or ice fields) that far south actually, in fact, are Antarctica. And to my knowledge there do not grow any trees there today? But of course, given the information in the above video, that's likely more due to the challenging cold (far below freezing) and lack of nutrients, rather than lack of sunlight...

[@jimkata77]

The trees likely lost their leaves and went into hibernation from the lack of sunlight just as deciduous trees do today from lack of warmth and light in the winter.

[@RobertBrown-ok2wv]

Shirin Rose Ya, wow. Maybe that's how early hibernation began to emerge.

[@pom7602]

Not to mention that life can adapt quite well over millions of years, not in a few decades.

[@firstman9273]

life will be here long after we die off.

[@vhawk1951kl]

What are you calling "life"? You have not the faintest idea? No surprises there. What would an ephemeral creature with an attention span of les than thirty seconds know of years or tens or hundreds or millions of years?

[@Cole-by9xs]

What about what they said was wrong? Why you so mad?​@vhawk1951kl

[@crazyjay6331]

Wrong.

[@jasonzimmerer8658]

“Not in a few decades” Retort: air conditioning

[@alfinito44]

the title of this video should be: when Greenland was green

[@herewardthewake3185]

@JP There's a reason nobody takes stone age numpties like you seriously - You're apparently too stupid to realise that by trying to attack science by misrepresenting it as a religion you're calling religion bad... So you just managed to insult yourself you utter lobotomite *slow clap*

[@PrZemek44]

@JP Yes. Actually, the last time the Earth got warmer was around 1920...

[@lrvogt1257]

@JP : You should read the scientific method one day and you may learn how appallingly ignorant you remark is.

[@ryanvess6162]

@@lrvogt1257 it's actually a great point. It's guesswork. Fancy guesswork. But still guesswork. You can observe the results in the fossil record but any attempt to explain it is just an educated guess.

[@lrvogt1257]

@@PrZemek44 : It has been getting warmer since the last record low in the instrumental record in 1909 and especially so since 1975. climate.nasa.gov/vital-signs/global-temperature/

[@SeanFication]

The globe has been warming for the last thousand years at least. That's why the last ice age is "the last ice age" and not the current ice age.

[@alexharbison4411]

The globe cooled for several hundred years but has been warming for 200 years now since little ice age.

[@sandal_thong8631]

I think scientists say we're still technically in an "ice age" because we have ice caps on Greenland and Antarctica.

[@alexharbison4411]

@@sandal_thong8631 Glaciers were growing from 1200 till early 1800. (little ice age) We are not currently in an ice age since glaciers are retreating.

[@DaveThomson-j9e]

​@alexharbison4411 not scientifically accurate. We're technically in an ice age. We are in an interglaical period

[@stevencole7331]

It would be interesting to see maps of the world with types of climates during this period for all areas

[@Now_lets_get_this_straight]

Because some areas that were hot then are now cold and areas cold are now hot. Something like what’s going on with the magnet North Pole moving in today’s world, oops, spoiler alert!

[@MrPaknight]

Just look at the layers in any hillside!

[@wsdimenna5244]

They don’t like publishing those because it destroys the man causes climate change

[@Jordello3000]

I can make one up for you

[@alisdairsmith5945]

@@wsdimenna5244 did you pay attention to the video?

[@bravo2p366]

There is a large bowl shaped area, south of Prudhoe Bay Alaska with alligator vertebrae and cyprus leaves. Coolest thing I have ever saw.

[@PV-re8kd]

Woah.. that's surely some sight to watch

[@antoniograncino3506]

Does it have a name ?

[@ModernGentleman]

Seen*

[@simianto9957]

Name?

[@vhawk1951kl]

Who told you that and why do you believe them?

[@reevethomas1083]

“There was a time, not too long ago...” yep, sure, I remember it like it was yesterday

[@a.randomjack6661]

50 million years is only 0,01111 of Earths history

[@underthetornado]

Lol

[@CeltofCork]

It was called "Age of the Politicians" and it's still ongoing. Global warming can be directly linked to it every time a politician opens their sodding mouth.

[@decimusrex92]

Reeve you are getting a front row seat to the most extreme example of climate change that no other living animal has ever witnessed 😁 Yeaah ! Excellerated into hyperdrive we are watching the very thing that keeps us alive change into something that won't be able to support almost 8 billion of us right now. Just imagine in 30 or 50 years (if your young enough) what an even more out if wack climate trying to support 10 billion. Ain't gonna happen.😖

[@reevethomas1083]

I have no idea what you’re trying to say, but I shall be around in 50 years as I am young enough. But shouldn’t you be extinct by now since you’re a dinosaur?

[@stephenmorse342]

The transient mantle plume under the Faroe Shetland basin at the end of the Palaeocene caused massive uplift of the ocean floor (minimum of 700m to 1000m) and cut off the ocean circulation to and from the north at the time. This has been mooted as one of the contributing factors. Also, a warming sea cannot hold as much CO2 so there is a chicken and egg scenario wrt CO2 and warming.

[@Avocadomolotov]

You know what I'd love? If you guys did a time line of life on earth with a map of the earth the way it was at the time you are talking about. It would help me get a better idea of life on earth.

[@jamesmule]

Erik Lervold Yup, that'd be awesome, with max/min temperatures, common animals, names of epoch, eons, ages and whatnot.

[@shelleysteva2251]

Not that different from now except for Northern Europe and Northern North America being very close to each other. That is another idea why it was so warm then- many volcanoes in the valley

[@Pikefish]

+

[@njebei]

I've always liked this video that is similar to what you want - kzbin.info/www/bejne/fX_QhpdqaNWUmMk It's not perfect but it helps me get a better understanding of how the world looked as things changed. If you want a book, I like Orgins by Ron Redfern. Easy to understand with lots of pictures. books.google.com/books?id=PqyMMs--IM4C&printsec=frontcover#v=onepage&q&f=false

[@Avocadomolotov]

thank you so much for that video! i am gonna watch it a couple of dozen times

[@oldibarra-tutu2253]

I Live in Australia and I want all our forests back and the our Koalas too.

[@foundunwanted713]

🌿🌱💚

[@wadeinn463]

Shouldn’t have loved all your coal.

[@scottleft3672]

They havn't changed, look at Mitchell's maps....the areas burnt last year are all...ALL... green again, you can just see the burnt wood through the green, the natives burned at leisure...and ate Koalas....lots of them....they simply didnt let the fuel build up underneath trees....as the flora here needs no furtilizer.

[@blogengeezer4507]

-Extreme Drought, fire conditions burning overgrown land mass, lasting many years, followed by extreme rainfall, flooding, lush overgrowth, lasting many years. The entire, endlessly repetitive life history..... of AUS

[@LK-pc4sq]

Its not going to happen. The sad thing is in the next 30-50 years if Co2 emissions continue its clime it will make most countries around the equator uninhabitable.

[@613naturalfitness2]

The earths history is so amazing and vast. Even if you spent every second of your life studying it you woudnt even get close to knowing it all.

[@garrick3rd]

Are you SURE??? WOW!!! Guess I won't spend ANOTHER MINUITE learning.... SOMETHING!

[@JustJessee]

Thanks for triggering everyones FOMO

[@electrictroy2010]

Now imagine being a cosmologist, and having to learn the history of billions of stars (and their planets) .

[@elizabethsullivan7176]

I wouldn't want to know it all. I like learning new things.

[@sergeymyasnikov736]

And that's why science was developed - so you wouldn't need to know every occurrence of something and could instead learn patterns. Also, your comment doesn't take into consideration a possibility for technological singularity and/or brain upload.

[@idiomasentusiasticos7954]

It’s so weird to think that at one point in time, the internal human body temperature was a cold day.

[@sion8]

The video should have either being subtitled or just titled _"When Greenland was _*_actually_*_ green!"_

[@sevtecsev]

Just think! When global warming is complete,we will be driven to the poles, all who stayed back will be fried. Those who have the skills to live in arctic zones will then be killed off by the new environment if they cannot adapt. When there is global cooling (via Milankovich cycles, perhaps,) those who have developed advanced technology will be frozen while hunter-gatherers at the equator will live, and a new society will emerge, without the advanced technology. No wonder ancient societies left evidence in large blocks of stone, only.

[@davidmanzi4491]

The difference is that current warming is man-made, back then, who knows? Don't dismiss warming based on political beliefs.

[@davidmanzi4491]

Yes, I have. I'm a born skeptic, and the science says that we're not only warming, but at a historic rate, and the trillions of tons of CO2 we're dumping into the atmosphere is a principal cause. Then again, maybe we can simply dump trillions of tons of CO2 into the air and it won't have any effect, right?

[@Junieper]

Charles Nelson Wait, so you're telling me that because CO2 is a small part of the atmosphere, it only has a small effect? In that case, would you like a small amount of strychnine?

[@Sectionmanifold]

Charles Nelson The medieval warm period is definitely reflected in Mann, Bradley & Hughes Hockey stick. It's just dwarfed by current warming. "ell have you considered that CO2 comprises just 1/25th part of ONE percent of the earth's atmosphere?" Have you considered how CO2 affects the IR window in the atmosphere and the other gasses don't?

[@qibli7679]

I love how the music in this episode sounds like a section from spore - which is fitting to this channel's theme.

[@jbw6823]

Spore?

[@titsmcgeeyolanda3755]

Lol

[@starlight0313]

Another WoF fan, *interesting*

[@tallymcdonnells5453]

Good one! But one thing I would have liked to seen addressed is the matter of sunlight. Even if the poles go tropical they still have to contend with having dramatically unequal lengths of daylight during the winter and summer. It could be that massive decomposition every winter had something to do with it. At the very least it makes me wonder if this with where the deciduous tree comes from.

[@Uluwehi_Knecht]

Even the tropics today have deciduous trees, it's not a trait restricted to temperate forests.

[@disconer]

If the Earth was perpendicular to the sun at the equator, would solve that

[@george2113]

The ginkgo is a living fossil. It is the oldest surviving tree species, having remained on the planet, relatively unchanged for some 200 million years. A single ginkgo may live for hundreds of years, maybe more than a thousand.Jan 15, 2020

[@TBonerton]

Deciduous trees do not lose their leaves unless the TEMPERATURE drops to a point where the lush green would wilt and die. It has nothing to do with amount of sunlight. All of the houseplants in my home continue to grow through winter, even though the light is about 1/3 of what it is in summer.

[@Mr.Unacceptable]

The poles were never warm the landmass that is the pole now was at the equator then.

[@RD9_Designs]

So nice to see a young Hank Greene here! I enjoy him so much on the SciShow channel! PBS should invite him back sometime. Soon! He has cancer!

[@kirbyarmstrong9174]

Exactly...the huge mass of plant life took CO2 out of the atmosphere. The only problem now is humans stand in the way of the spread of plants.

[@stevenpeterson191]

Yep, I for one kill plants whenever I encounter them. You know, being a vegan and all.

[@retret9946]

@@stevenpeterson191 🤦‍♂️

[@tonyromano6220]

Lol humans are a minimal impact, other than plastic in the oceans.

[@user-yn9mp4bt3q]

en.m.wikipedia.org/wiki/Carbonate

[@eugenexia3634]

I want to know how much of the current land mass was under the ocean during that warm period.

[@latenighter1965]

Large portions. Our ice caps are only a few million years old. They documented this in one of their episodes. Yet once the ice age hit our oceans dropped drastically, we know this also because we found cities that were are now under water that were above water 5,000+ years ago.

[@jbw6823]

There are sites on the web that can show you this.

[@perrysmith1838]

I think sea levels were 75 metres higher.

[@jbw6823]

@@perrysmith1838 similar to the 200 plus ft mentioned above your comment

[@perrysmith1838]

@@jbw6823 I didnt read the comments i just answered. But now at least the Europeans will understand .

[@cascas1116]

I agree with you, 56 million years ago is not long ago.

[@StoryGordon]

The two most recent global warming trends were during WWII (Can you guess why?) and during the last five years. The data is here data.giss.nasa.gov/gistemp/

[@marioandloveyaplushmasters3374]

Now try the eemian warm period

[@StoryGordon]

@Slomofogo - ? The process is very simple. Global warming causes evaporation putting moisture in the atmosphere which has only one way to go. Rain, snow, both are the same effect. Cold and warm temperatures are due to the tilt of the earth's axis. Global warming increases all precipitation.

[@notthisguy5068]

How long before you can "skip ad".

[@randysavage1]

@@StoryGordon stop using science to school us millennials who get climate change information from netflix and face book. Its not like EVERY STUDY where they tested ancient ice, shows we have a major ice age after 100000 years global warming......oh thats right they do

[@Delgwah]

Thank you as always, great to watch for sure.

[@kylealexander7024]

20°C is 68°F for anyone wondering out there. Sounds like the arctic woulda been real nice to swim in

[@elizabethsullivan7176]

And at the rate we're going we'll be able to swim in it again soon.

[@vere9652]

If U.S. would use Celsius like the rest of the world, that would be amazing

[@kylealexander7024]

@@vere9652 we use both but sure. For example my 12 oz beer is 355 ml. Virtually everything is measured both ways here. Its not that hard to change degrees to celsius. Every degree C is literally 1.8 F.

[@kylealexander7024]

@@elizabethsullivan7176 i honestly dont think theres any way to change it at this point. We needed to start decades ago to have any meaningful impact. Our species is very reactionary in general. Dont tend to deal with problems outside of the time we can fathom

[@jean-marclamothe8859]

Kyle Alexander 😅😂🤣 go listen to Hans Rosling video on how to stop to be misinformed

[@vigilantsycamore8750]

As TV Tropes put it: imagine all the dangers of the rainforest, AND IT'S DARK FOR HALF THE YEAR

[@vigilantsycamore8750]

"Everything Trying to Kill You."

[@icwiz]

wait. wait....how DID that work? How do you have rainforests in places where the sun doesn't shine for 6 months out of the year?

[@taylorwestmore4664]

I want a paleo-botanist to explain that one for me too. Were plants in the highest latitudes adapted for some crazy hibernation period? Like Evergreen trees that went dormant for 6 months?

[@Areanyusernamesleft]

icwiz it's an exaggeration, but some parts of polar regions can spend a few weeks during winter without the sun appearing to rise above the horizon.

[@terpjr]

Exactly! The models are easy to rely on, but they don't always mesh with common sense.

[@krzyktty101]

I think a video about the birth of the Appalachian Mountains and what has made them stay around so long would be interesting.

[@tr33m00nk]

@krzyktty101 & @Sean Cauffiel Since you're interested: the Appalachian Mts. have at their core precambrian rock called the "Grenville Province" which extends in a band from Mexico to Labrador, Canada. It's over 1,000,000,000 (billion) years old. There are younger sedimentary rocks on top and so it gets complicated. The Adirondacks are an exposed part of the Grenville Province and part of the Appalachians. For more mind altering details read "Written in Stone" by Chet & Maureen Raymo >> www.amazon.com/Written-Stone-Chet-Raymo/dp/1883789273/ref=sr_1_4?ie=UTF8&qid=1545409730&sr=8-4&keywords=written+in+stone

[@davidbarrett590]

Thank you for a serious presentation given briefly. I am 70 and when I was a student at Cambridge the serious academic opinion which was widely communicated in public was that Earth was heading for a serious cold period if not new Ice Age which would be triggered by a short and minor warming caused by pollution.. That was 50 years go - but 50 years is really very short time and I would like an explanation sometime - from you or anyone else serious - at to why opinions have changed. so dramatically. Could it be politics rather than serious science?

[@mcgritty8842]

A lot happens in 50 years. Just look at the population boom alone, plus there’s more nuclear testing now than back then. How many countries are running tests in the Artic and destroying it in the process??

[@azpete6436]

The axial tilt oscillation also is in play, causing the arctic circle to shift to the North.

[@azpete6436]

@Marcus Maris can't stand facts?

[@Psyclone500TV]

@Marcus Maris How about you shutup and look at all the proof of how real this is

[@selenaichtis6762]

@Marcus Maris Learn basic grammar before telling others to shut up.

[@iancurtis1152]

The magnetic poles are shifting constantly as well.

[@klauskarpfen9039]

These are much shorter cycles than the one he is talking baout, which was an extra-cyclic event that started with a yet unidentified cause for emission of greenhouse gases.

[@tonytackett2885]

I would love to share with you photos of petrified Palm trees still visible in the mountain railroad cut away in Southeast Kentucky . Approximately 20" in diameter . Solid rock but crumbling .

[@paul9120]

Just do some research online and you will find many, many things that so called science does not talk about. There are petrified giants all over the Earth....why don't they point these out. There are many fossilized footprints of man alongside dinosaur prints......they do not point these out either. Those of them who who even try to point these things out will be snubbed and chastised for it....you know, like termination of funding for research. The people who hold the money purse control the narative and guess what....their narrative will not lead you towards truth.

[@vhawk1951kl]

You have " crumbled said rocks for yourself? No, I rather though not. Whoever said that men (human beings) are as credulous as imbecile children is obviously the patron saint of those in the business of lying for money or in the advertising business.

[@m444ss]

@@vhawk1951kl ??? what ???

[@chrishenicke2052]

There are big pieces of petrified palms in south Texas too.

[@robbyddurham1624]

I've got a tree fossil that looks like a snake skin. It's some kind of palm tree. Found it here in Kentucky in the outlet of a mountain spring, mouth of a small creek.

[@brittemiller8939]

Commnets and engagement here is just as interesting as this video . Great job everyone!

[@janemorrow6672]

Fantastic video. Shared multiple times.

[@austinross5188]

Polar dinosaurs would be an interesting topic. Many species of very different forms were present within the arctic circle, including hadrosaurs, tyranosaurs, dromeaosaurs, and ceratopsians. We know some of those species to not have any evidence of feathers, going as far as to have evidence supporting the contrary (hadrosaurs, I'm looking at you). These must have been some pretty resilient animals to have been so successful in that region.

[@extradeluxe141]

My only guess would be Continental Shift. Those "polar regions" were probably by the equator at that time.

[@homurseempsone154]

you've got it. There were no arctic regions back then like we have today. Although, Australia during the Cretaceous was very close to where Antarctica is now. Thats why a lot of dinosaurs from there during that time have such big eyes compared to everywhere else because of the months of darkness

[@bundleofperceptions1397]

WTF are you talking about? That region was lush with vegetation, so why would they need to be resilient?

[@aaronelijahcolyer]

or there was just no ice or very little at that time... a comet hit the earth at one time and flash froze parts of the planet, that's how the woolly mammoth was frozen standing up with food still in its mouth... our planet has been warming every since

[@Vulcano7965]

My inner geologist screams with joy everytime I see a new episod of Eons. You guys do your homework, thanks for being awesome!

[@jeffreyvences4361]

Bew things are awesome!!!

[@Vulcano7965]

@@jeffreyvences4361 they are indeed! :D

[@vhawk1951kl]

Try aeons, not that it signifies or matters

[@Vulcano7965]

@@vhawk1951kl It's the name of the channel? Not sure what you want to say.

[@vhawk1951kl]

@@Vulcano7965 What is the name of the channel?- Nonsense for credulous Elsies?

[@ssssaa2]

1 trillion times better than Snowball Earth.

[@Sectionmanifold]

No.

[@ri3m4nn]

Yes

[@Sectionmanifold]

@@ri3m4nn I don''t think you understand how hot it its going to get. A superglacial event would be bad but you could counter it with CO2 buring as much coal for heat as you like. Current projections for current emmissions lead to humans being limited to the Arctic circle and perhaps AntArctic colonies in a couple of centuries.

[@ri3m4nn]

@@Sectionmanifold actually, we know. Google: PETM

[@ri3m4nn]

@@Sectionmanifold here, let me help you: kzbin.info/www/bejne/r3rTdaGdfNJombM

[@anime5h_m1shr4]

Awesome video as always. Once again wish you the very best for a speedy recovery, Hank. You got this.

[@chuckrambo4401]

Some people think the Earth has never gone through changes except for the Industrial Age

[@scottabc72]

The changes from the Industrial Age are happening much faster than natural processes with the exception of things like asteroid strikes and megaeruptions

[@timwade1266]

your point? Eruptions still occur and they are more "mega" than the combined effects of the Industrial Age. Additionally, its not possible to gauge the effect of man since 1.) man is here and 2.) who would do the measuring.

[@scottabc72]

@@timwade1266 Its not possible to perfectly gauge any kind of complex system if its complex enough and thats certainly true of planetary climate. There are plenty of ways to get good information though about the past, ice cores from glaciers for example. There are plenty of smart people who have jobs figuring this stuff out. We cant stop a mega eruption from occurring but we definitely can and should control our own behavior.

[@dpchait7793]

These are the same people who believe that they need to get the current corporate global governance injection

[@johnbatson8779]

@@scottabc72 complete nonsense, the globe had an accelerated warming period from 1700-1730 and was not related to the Industrial Revolution...and the medieval warming period, 1000-1300 CE, actually caused viticulture to occur both at Greenland and Scotland. so the temps must have risen more than 2 degrees C to have this phenomenon to occur

[@TerryJLaRue]

Interesting video. However, I heard no mention of the Milankovitch cycles, which have to do with 3 changes in the earth-sun relationship. They are precession, a cycle of about 25,000 years, axis deviation, over about 40,000 years, and orbital changes, which cycle about every 100,000 years or so. These changes have significant effect on climate change over long periods. They have no noticeable effects over short periods of, say, 3 or 4000 years, but over the much longer term, they are very significant.

[@angeleyes2c]

PETM is not linked to Milankovitch cycles but to volcanic activity releasing co2.

[@mrpoquah]

@@angeleyes2c as in the Siberian traps that dumped some 700,000 cubic miles of rock and lava to the surface. Just think about the C02 levels when that finished.

[@brianhillis3701]

@@angeleyes2c which this video goes to great lengths to say is not true. That would mean they need to explain the vulcanism. They say it is biogenic carbon. They have great faith in carbon ratios where it has been proven that too many things like decay and sunlight alter the ratios significantly and beyond about 12000 years ago it is meaningless.

[@Ivan.A.Churlyuski]

Mid warmth of the Holocene period 6000 years ago vs the climate today suggests to me they have a large noticeable effect.

[@blakessite]

I was just going to say that.

[@daveat191]

How about a timeline between Ice Ages, sea levels, warm periods, the homo species, forests and desertification, super volcanoes and their relationships ending with current global warming.

[@electrictroy2010]

Wikipedia has several timelines showing the changing temperatures over the last 4 billion years. The earth cycles back and forth between Ice Ages and Tropical Ages (no ice on the poles) .

[@lunaflamed]

Don’t forget THE SUN. You can forget the Grand Solar Maximums and Grand Solar Minimums. Not like the Sun is the biggest most powerful thing in our entire SolarSystem or anything.

[@lostmrsmoss]

Good info... I had to slow the video to 75% speed. When the speaker talks so quickly, my brain doesn't have time to process one bit of information before the next one comes.

[@mcgritty8842]

But you’re old…

[@rudigereichler4112]

Please make an episode ”The last time the globe cooled”. After all ice ages are longer than interglacials.

[@Mordalo]

No money in reality, just fantasy. Hollywood is proof. :)

[@jillian2851]

This would tend to reinforce the opposite of what these Globalist and Socialist are intending. Americans are being brain-washed by Socialist media and to make matters worse, we are paying for it as well.

[@stevegrimes3664]

No, this has nothing to do with ice ages or interglacials. The PETM was 56 million years ago, the current glaciation began ~2.6 million years ago. (The last ice age before that ended 260 million years ago.)

[@DarrenSemotiuk]

So weird that graph @9:16 only goes back as far as 1880, instead of, say, the 1400s... Can't imagine what that reason is :hmmm:

[@jwarmstrong]

@@DarrenSemotiuk Few temperature records were kept except +/- 2 degrees because most thermometer were not accurate - the earth is 200 million sq miles so satellites are required to measure everywhere

[@seancassidy4812]

Please do one on the medieval warm period when the Vikings lived in Greenland and, the historical record from the Arctic where people travelled to 81 degrees 29 mins north in the year 1923, the furthest ever recorded. Also, should ye have the time to examine it, the events in Europe in the early part of the 1700s, when the Seine and the Loire dried up so much that people were able to walk across them.

[@jean-marclamothe8859]

They won't do that you know hey?

[@fredblogsmac.5697]

Yip it was way warmer in the 80.s with drought in the U.K. and the hosepipe ban look at it now.

[@PremierCCGuyMMXVI]

The Vikings never lived in Greenland, or at least the way people think they did, the medieval period was not warmer than today, and the Arctic is much warmer now than it was 100 years ago Edit: I should clarify, there were settlements there but they weren’t farming or anything like that across the whole continent. Greenland was a lot like it is now and people live in Greenland today.

[@fredblogsmac.5697]

@@PremierCCGuyMMXVI yes they did there buldings are still there. A bit brocken down with time but still there.

[@fredblogsmac.5697]

@@PremierCCGuyMMXVI there,s runes on Greenland still to this day a bit broke down but there still there

[@LimeyLassen]

Whatever new life arises post-Anthropocene extinction is gonna be pretty wild. The age of mammals came from the fall of the age of reptiles. What new species will profit from this chaos?

[@globin3477]

Let's leave lots of bronze statues behind so that any intelligent life that forms will know we were here. (I say bronze statues because, to my understanding, that's the type of evidence that will most likely last long enough to be found in a few million years.

[@edlingja1]

Well probably a titanium-ceramic alloy, but yeah bronze. But no, we are the highest form of life that will exist on earth. The concept of cancer, is a good analogy for humanity on earth.

[@luciferangelica]

Slime and viruses

[@lilaclizard4504]

age of the octopods

[@SysterYster]

Globin347 Stone I think lasts longer. Especially in en environment with high CO's.

[@seniorskateboarder5958]

I like stories about the earliest life in earth, the giant bugs and spiders being the dominant life form. Also, the different kinds of stationary animals that grew in the oceans. And that giant ice age wherein even the oceans froze over. I find all that fascinating. I wonder how big the spiders got!

[@user-yv6vx]

I would love to know how big the spiders got. Also, people say animals like shrimp are the insects of the sea and yet they have meat we eat. If a spider leg was as large as a chicken leg, I wonder if it would contain tasty meat

[@electrictroy2010]

Insects originated in the sea as shrimp, lobsters, crabs, etc. They evolved the ability to extract oxygen direct from the air & live on land

[@electrictroy2010]

Snowball earth is when ice covered the whole planet. Almost no life existed then

[@DrSmooth2000]

@@electrictroy2010 Runaway Icehouse Effect check out the Azola Event. I'm worried if geoengineering tips us into such a spiral

[@vhawk1951kl]

You*would*ike stories about the earliest life in earth, the giant bugs and spiders being the dominant life form, but do not seem able to grasp that they are *only* stories. The definition of a *story*? Anything you are told* , but cannot verify for yourself. What you call the past, and science, are no more than*stories* Of course you like stories, because you are passive and they require nothing active from you. Beings of the passive sex or women are and must be passive in relation to beings of the active sex; nothing active is required if them; for you the story is the active and you passive-nothing is required of you. It is not just you in particular but all man(human beings) They just passively accept what they are told, true?-not true? Why do you suppose it is that all men including you and your servant here present are so passive? whose or what's purpose are served that you, I and all men (human beings) are so predisposed to be passive?

[@delatorrecaleb]

A large volcano eruption can take over the whole atmosphere.

[@JBebop84]

Caleb Delatorre Yosemite will do that

[@dzerres]

It's probably our only hope to cool the planet at least temporarily. The only problem is there's no control over how much and how long. Either way we, over the long run, are screwed.

[@bundleofperceptions1397]

So can a large meteor, so what's your point?

[@lrvogt1257]

Yes, but most volcanic eruptions have a fairly short term cooling effect. Industry produces 60 times the average annual output of CO2 as volcanoes. And we have no control over volcanoes. We do have control over industrial emissions.

[@kenprice1961]

@@JBebop84 Nothing in Yosemite...…….maybe you meant YELLOWSTONE.

[@owensuppes1]

I just want to point out that the Eocene maximum was not the same baseline we are dealing with in today's Holocene maximum( the narrator mentioned this as well). So comparisons of emissions and radiative forcing only go so far in informing projections.

[@DrSmooth2000]

what do you mean by baseline?

[@owensuppes1]

@@DrSmooth2000 we are currently in the Holocene, an interglacial period. So we're on the hot end of a fluctuation between our current conditions and an ice house. Carbon concentrations are very low in our atmosphere compared to the Eocene. The oceans were much warmer during the Eocene

[@DrSmooth2000]

@@owensuppes1 see nothing to disagree about guess lack structure of a class to learn methodically. am I correct in you're saying that upping it 100ppm 'hits different' when talking 600-700 vs 400-500? just learned last night via a comment here of the Eemian Period 115kya that earth is only negligibly different than ours geologically. Gap I'd seen in the ocean currents being so different between now and MMCO. Seems like biosphere did great in Eeemian. At a mesoscopic level, any idea why Midwest (and Prairie Provinces?) are the one region drying right now? Or, at least suffering summer aridity, I believe is more precise. Saw explanation in MMCO that the Rockies being newer and higher had more profound rain shadow. In Eemian the forest belt extended into West Texas. 100k of time would only reduce Rockies a tiny bit so if anything should have negligibly less drying effect on Plains.

[@DrSmooth2000]

Learned more since. Looks like we were facing precipitous glaciation until the carbon emissions

[@owensuppes1]

@@DrSmooth2000 the earth is greening at an incredible rate since the 70's. The bulk of that greening is due to atmospheric anthropogenic CO2. Moving from 280pp to 400+ ppm CO2 has supercharged plant life. This effect is observable on the prairies. Crop yields are increasing as well plants are better able to cope with aridity due to less reliance on water. There are several papers on "global greening" that you might find interesting. And I'm sure animal life is not "generally" adversely affected by global greening. Something like 40% more green globally. It's funny this subject is not talked about As for a 100ppm increase, the effect is logarithmic. With the most profound effect early and a saturation point toward the end of the log. Equilibrium Climate Sensitivity (ECS) is calculated using a doubling of atmospheric CO2. The accepted range of warming caused by a doubling of CO2 is projected to be between 1.5 and 4.5 Celsius warming. With low confidence in the high and low estimates. But, observations have not so far supported the mid, 3C/ doubling. Back to the Holocene, we are not in the warmest period currently. That would be the Holocene optimum.

[@oldmanonhill8366]

Question. Does this mean since I live in Georgia right on the fall line, which means at that time that was the level of the ocean. in 3000 years will I be enjoying oceanfront property?

[@thelivingdead1728]

The state or the country ?

[@St-benoit]

probably more like in 100 years lol

[@thelivingdead1728]

@aghori sadhu Thanks

[@kentmerrill8925]

vALUES SHOULD BE GOING UP SOOn

[@oldmanonhill8366]

@Tonto Y Quiennosabe I hope you know who gave you the first thumbs up because man you are so right.

[@BrianEthridge-wk6hz]

I can't even begin to tell you how much I love these videos! Thanks so much!!!

[@sellers737]

I never want these videos to end

[@eons]

Yay, because we never want to stop making them! (BdeP)

[@TheRickerX]

Don't worry, they go on for eons.

[@sizanogreen9900]

I'll take your word for it:3

[@lorekeeper685]

Rick Janssen wynut aeons?

[@chatteyj]

What about that big orange bright hot thing in the sky, does that have any effect on the planets temperature and climate? Clue: it does. (A very big effect.)

[@allancrow134]

I can't imagine a tropical forest in the Arctic because it's an ocean, albeit a currently frozen one. When it thaws it will still be an ocean except it will be 200 ft deeper. Now a tropical forest in the Antarctic, I can imagine that. :)

[@Yuēhàn24]

When the Arctic was a tropical forest the continents were in a different position to what they are now.

[@faytleingod9592]

I love this point

[@BrugersUK]

There's plenty of land in the arctic. Ask Norway, Finland, Sweden, Greenland, Canada, the U.S and Russia. The arctic starts at 66° 34' N

[@allancrow134]

@@BrugersUK Of course. :)

Northern Alberta Canada once had crocodiles.

[@kimweaver3323]

That was when it was much nearer to the equator. Continents move, you know.

[@haroldcochan3971]

They still do, they live underneath my trailer in Edmonton.

@@haroldcochan3971 no those are just newts. Everything is bigger in Edmonton.

[@lukula2934]

Yes and You can find prehistoric shark teeth all over the Alps...Change is the only constant.

[@angrytedtalks]

I thought he was a lobster? And moved to Toronto as a Psychology Professor...

[@sandal_thong8631]

I looked up a map of the world from 45 million years ago. North America looks similar, except without Florida, Panama and Central America. Northern Eurasia looked similar. This was before India Plate hit Asia raising the Himalayas and the African Plate hit Europe raising the Alps, so lots of seas in those locations. There was no Red Sea; the Mediterranean was open to the Indian ocean via the Persian gulf and closed to the Atlantic.

[@zekelerossignol7590]

You should do a video on Earth's recovery from the KT mass extinction sometime.

[@jc.1191]

Katie is pretty ruthless...

[@allenroach7503]

Well there you go. You could slap me with a hockey stick!

[@1pixman]

Ha ha ha Michael Mann mr Hockey Stick Just Lost his Case because he Refused to Show How he Got the Numbers he Claimed Caused the Hockey Stick to Curve up.

[@johnnikitakis876]

Well done, I hope everyone got it.

[@rocky5152]

Allen Roach consider yourself slapped via hockey stick! 🏒🏒lol

[@pacalvotan3380]

@@somesilentthoughts5503 Well then you're calling Dr. Tim Ball a liar, because he's already stated this publicly: kzbin.info/www/bejne/mpTHgYBre75ri8k

[@danlalib4292]

1pixman 👍🏻 I discuss this subject with people way more educated than I am and I would consider myself a deniar. Where did you here Mann couldn’t prove his hockey stick theory? I need amo lol

[@scottcaldwell8515]

Thank you for leaving references. Not enough people do.

[@rhrh2025]

Half of it warmed up last summer, and it's doing it again this year!

[@disco1974ever]

Actually this was bang-on!!! I would like to see more about Earths Climate History thanks.

[@SirCharles12357]

I'm curious about how the coral reefs survived this event.

[@elijahmikhail4566]

Because it happened in the span of millions of years, coral reefs probably had time to slowly migrate into warming seas towards the poles.

[@SKy_the_Thunder]

Some corals survived somewhere and (re)-populated the reefs we know today once the conditions became more favorable.

[@scaper8]

As others have said, it was the speed of the change. In natural warming and cooling cycles (even really extreme ones like this) it takes long enough for species to move and/or adapt. When it happens too rapidly, like now, there isn't enough time for most species to do so.

[@MrMartibobs]

Although coral reefs have been around for over 500 million years, the Great Barrier Reef for example is relatively young at 500,000 years, and this most modern form is only 8,000 years old, having developed after the last ice age.

[@SiRGnOmEGuY]

scaper8 - according to the sun, we did this already in the 1600-1700s. maunder minimum.

[@phoenixfoster-smith8585]

"The last time the globe warmed" was, in fact, not Eons ago, it was about 7-9 centuries ago when the temperature of the world rose by 16 degrees Celcius in 5 years. and this is the reason we have the cold centuries in the 16-1800s.

[@DavidLister77]

Yup. There was the "Roman Warm Period", followed by the "Dark Ages Cool Period", then the "Medieval Warm Period" and then the "Little Ice Age". Apparently, these facts are irrelevant.

[@wrightway3382]

We are still coming out the last mini-ice age

[@amitypearson6879]

you are aware during these exact times, wood, was the weapon of choice, both land and water. It was also a status symbol. Hence mass deforestation. Who knows how that effected things???

[@wrightway3382]

@@amitypearson6879You are correct about the importance of wood. But no mass deforestation for many reasons "outside of Europe" - populations were concentrated and much, much smaller, the mini-ice age killed off quite a bit of the population in the concentrated and outlying regions from starvation, then lets add constant wars, disease not including the almost genocide of mass population in Europe and middle east from the Black death "Bubonic Plaque" along with short life spans and staggering infant mortality rates. It was a hazard to even drink water in the dark ages! This is the period "we have not recovered from" after the Vikings settled the very green areas of Greenland in 1003 AD before the mini-ice age.

[@FloatingOer]

@@wrightway3382 You also got the Aztecs who were chopping down massive amount of trees to make farmland for their growing population, they chopped down so much there was literally less rainfall, meaning crops didn't grow as well, meaning they chopped down more trees to make new farms. When the Europeans arrived their cities that used to house up to a million people was all but abandoned from the starvation, they sacrificed hundreds of people a day to the sungod (or to lower population?). So there was definitely places outside Europe with large deforestation.

[@sebachinger]

Love this channel and the information that you share in a way that is great for all folks to absorb and understand :)

[@TomXCZD]

Rain-forests in Canada sounds amazing.

[@user-yn9mp4bt3q]

We have rainforests in canada

We totally have rain forests in Canada.

[@martinmichalak3938]

Unfortunately, Central Canada will be underwater. Also unfortunately, that's where most of the food comes from.

@@martinmichalak3938 what?

[@martinmichalak3938]

During the warm period in the Cretaceous, much of central USA and Canada was underwater. The flooding during the time discussed in the video was not as bad, but still. Also, the crust in that area is still depressed from the last glaciation, so maybe flooding will be worse in some areas. Anyway, today we use the Great Plains to grow our food, so losing all that to the ocean would be a disaster.

[@fakereality96]

I miss the days when we were all proud of having saved an acre of rainforest, the internet wasn't really a thing, and the hardest choice that had to be made was Super Nintendo or Sega Genesis.

[@ginablanshard8255]

yes - and it's impossible to 'un-know"

[@ModernGentleman]

Super Nintendo, obviously.

[@blackiedekat2612]

........and .Frogger' was available for both...............................

[@irishart4793]

Ahh come on guys don't worry about it, we are just one supervolcano away from becoming extinct and the planet gets a new type of life form

[@Kimoto504]

Except the supervolcano is just hypothetical. Human induced climate change is a given. The presenter glanced but didn't elaborate on another important fact: We're causing the temp change rapidly which gives virtually no time for us or other organisms to adapt. PETM took thousands of years... enough for our predecessors to evolve significantly.

[@irishart4793]

@Alexander Supertramp I wanted to come back hard at your reply but I loved Supertramp so I will just say "maybe not but it will mess up your day off"

[@StarboyXL9]

Nothing wrong with that. We've obviously failed. I say the next species should het their chance. I'm rooting for octopi Also. Man-made climate change isn't real. Stop acting like children and believing everything old people tell you.

[@irishart4793]

@@StarboyXL9 😂🤣 octopi haa ha love it, I am rooting for crabs 50 ft crabs or crustacean tanks yaay

[@hypershard8935]

Joel Gawne do you have anything to back that claim up?

[@HighlyCompelling]

125,000 years ago, the climate was warmer than today and see levels 30 feet higher. This coincides with modern man leaving Africa. Human evolution is directly tied to climate changes.

[@astrovation3281]

We couldn't have done anything back then to increase Co2 or warm the climate

[@HighlyCompelling]

@@astrovation3281 I didn't mean it was caused by humans leaving Africa. I mean the warming climate caused humans to leave Africa .

[@Wildblood]

Would love to know more about the Huronian glaciation - when the Earth was a gigantic ball of ice. Were all oceans covered in a sheet of ice, like Europa? How did the planet recover from that to become more hospitable to life?

[@davidkelly4210]

Nothing was said of plants.

[@Batowl1]

Oh, I misread planet as plant

[@Thunder_Dome45]

If I remember right I saw a show on the history channel and they said volcanoes started going off to end the snowball earth. Now it's been 10 years since I saw that so I could have my chronology a little mixed up.

[@bundleofperceptions1397]

Yes. Volcanic activity put enough greenhouse gases into the atmosphere to warm the planet up again.

[@PremierCCGuyMMXVI]

A rise in GHGs (mainly co2) due to volcanic activity thawed the Earth

[@zpetar]

3:09 Wouldn't all those massive wildfires release massive amounts of ash, dust and smoke in atmosphere too? Did anyone ever made simulation how would that affect climate? Would would happen? Warming up because of CO2 or cooling down because of ash, dust and smoke?

[@isakbonaventura2825]

Good point!

[@a.randomjack6661]

Ash, dust and smoke stays up there for a few months at the most. Usually, less than one.

[@jbw6823]

Yea we could start fires all over as a form of geoengineering. Hmmm...maybe not a good idea.

[@KingComputerSydney]

Its relatively easy to cool the climate if we want to by putting extremely high stacks and emitting sulfur dioxide high into the atmosphere or other specifically designed aerosols. We can also cost effectively pump sea water onto the poles to increase ice mass and albedo. The hard bit is warming the climate as CO2 has so little greenhouse effect we could never get enough of the sequestered CO2 back into the atmosphere for it to create significant enough warming, unless we start burning kilotons of limestone as well as fossil fuels.

[@centsible12]

@@jbw6823 We don't have to, they're already burning

[@LEDewey_MD]

Very near this Eocene cooling period, both the Chesapeake Bay Asteroid Impact and Popigai crater impact in Russia occurred about 35 million years ago. Those could've helped with the cooling.

[@vhawk1951kl]

Who told you that and why do you believe them? It is of course complete nonsense to speak of "the globe" (which is presumably a reference to the planet earth), having *a* temperature - one figure that says it all, because that is a thermodynamic and mathematical impossibility. It is no more possible for there to be a global temperature than it is possible for there to be a global telephone number or blue Wednesdays

[@fauxque5057]

I thought it was common knowledge that asteroid impacts kicked up clouds of dust that blocked the sun?

[@vhawk1951kl]

@@fauxque5057 There is no such thing as "common knowledge - nor could there possibly be, just as there is no such thing as a common headache. Nothing about the past can be directly immediately personally experienced or verified or known, so it is nonsense to speak of knowledge of the past - it can only be information, and men (human beings) to be the divide into two groups, the one that clearly understands the difference between knowledge and information, and the other that has not the faintest idea that there is any such difference.

[@petitio_principii]

@@vhawk1951kl there is such thing as common headache, though (vs less common types of headaches), just as common knowledge (vs less widely spread knowledge). But if we're going to get all sophisticated, then maybe words don't even exist and whatnot, all depends on what one's definition of "is" is, ad infinitum.

[@avinashreji60]

@@petitio_principii The person above really loves to pretend he’s brilliant

[@ant-1382]

Good documentary, nice have it a little longer and more detailed.

[@robertchristensen937]

Don't you think warmer climate means more evaporation and more clouds, reflecting heat out to space and having a cooling effect.

[@charoncross6696]

Sure. Clouds can reflect light back into space, but water vapor is a greenhouse gas.

[@N.Sniper]

@@charoncross6696 It is in fact the most important greenhouse gas, being 95%^of the greenhouse gasses.

[@mattlitton1255]

Nobody is really sure how it balances out. Clouds and cloud formation are very complex chaotic systems. Most of the uncertainty that remains in climate models comes from scientists being unsure what clouds will do

[@marksherrill9337]

You mean green house effect .

[@geckovonparsley8200]

I would love an episode on how fingernails developed.

[@ALXMARTIN]

Gecko Von Parsley why

[@demonicsnowh.280]

I believe they covered it in a episode, or it was explained in one of their videos about hominids.

[@michaelcampbell5567]

Fingernails were claws at some point and as they had less impact on survival, they faded away million or so years ago. Some primates still have claws.

[@scottleft3672]

CLAWS.

[@rogersimon3336]

@@michaelcampbell5567 you can still make them into claws ya know. Just gotta plan it out, and sharpen as you want and they naturally curl out so there you go

[@kristinessTX]

There are ferns all over Alaska today...well not all over...but they are abundant.

[@NiftyShifty1]

And under. You forgot the under part. Ferns are all over and UNDER Alaska.

[@askmagoo826]

simply put, if earth goes hey wire very hot or very cold. Humans will be affected and likely go extinct. While earth goes meh, I'm just chilling

[@caseyferguson6076]

It's amazing how we know all of this. Yet none of us were alive then

[@ShellymanStudios]

I was.

[@MF-LXRD]

It's not amazing it's called science.

[@alanstephens7022]

Casey Ferguson we Don’t know this. The data is wrong because it dismisses the Sun and it’s well known cycles. It’s known as Solar Forcing. Unfortunately the case is more dire.

[@ZeVexGaming]

It's amazing how scientists live in space, orbiting our planet. Yet space is inhospitable to humans.

[@shaun6828]

@@alanstephens7022theness.com/neurologicablog/index.php/solar-forcing-and-climate-change/ The science behind how CO2 reflects infrared light and the human extraction of CO2 deposits from below the earth's surface are easily demonstrable and pretty obvious causes for global warming. scied.ucar.edu/carbon-dioxide-absorbs-and-re-emits-infrared-radiation Visible and ultraviolet sunlight hits the surface of the earth and warms it. The warmed surface emits infrared radiation (like what night vision goggles view). That radiation mostly passes through the atmosphere and escapes to space. When you add some extra CO2 and it's a bit like adding some silver on a piece of glass. You get a mirror effect that reflects more of that infrared radiation back at the ground where it is absorbed again. It's just a small increase in energy being trapped, but overtime it adds up.

[@LemurWhoSpoke]

Next: Early primate evolution… since this episode was such a great segway into it. After that, do something almost no one has talked about: the extinct giant lemurs known as subfossil lemurs.

[@rafaelalodio5116]

Nice suggestion, I would also like to know why there aren't Primates in North America anymore.

[@LemurWhoSpoke]

Rafael Alódio Primates went extinct in North America around the end of the Eocene due to the cooling climate. Tropical forests became seasonal, temperate forests, with winters offering little to no food and cold weather. The same happened in Europe. I wrote about this on Wikipedia in the article covering the evolution of lemurs and the article on strepsirrhines.

[@LemurWhoSpoke]

Appending to my suggestion, please, please, please study up on the latest research if you do something on early primate evolution. If I hear the suggestion that "Ida" may have been an early ancestor of monkeys, I will smash my phone against the wall. That idea has been thoroughly discredited, and was never based on a sound principle anyway. If the Eons writers need me to explain, I will.

[@LemurWhoSpoke]

Taking this suggestion yet another step further, a video on early primate evolution would be a great opportunity to discuss the Ida debacle, where it could be used to help people understand the two major branches in the Primate family tree and how they diverged… in addition to explaining the history of our understanding of primate evolution.

[@downbntout]

You confuse the Segway, a mobility device, with a segue, any smooth transition.

[@unknownpawner1994]

The Last Time the Globe Warmed Greenland was actually green.

[@daniellewis984]

The last time the globe warmed substantially was the end of the last ice age, between 26,000 years and 11,000 years ago. The sea level rose 300ft as the glaciers receded, and the temperatures rose substantially. So goof ignoring the fact that we just came out of a huge ice age, and we keep having them.

[@michaelcampbell5567]

Widespread non-native colonization of greenland in the 1200-1300s. Historical record indicates the period just before the little ice age much warmer than now.

[@reinhardweiss]

Michael Campbell yeah, the barbarians and their f’n SUVs that they drove across the ocean, running over all the polar bears!!! 🤪🤪🤪🤪

[@bundleofperceptions1397]

Why do people think that is a remarkable fact?

[@nata3467]

love all these mini documentaries

[@geoffwright9570]

Always thought that this planet as a living entity. It continues through its cycle regardless of what animal was living on it. Now it's our turn to experience it's present change.

[@ModernGentleman]

Right. How arrogant these people are to honestly believe we're hurting this planet. We are BARELY a surface nuisance. This planet was here long before we showed up and will be here long after we're gone.

[@richardthompson5436]

@@ModernGentleman "Long", is an extreme understatement.

[@ColinBarrett001]

@@ModernGentleman True enough Don, the planet will eventually recover when we're gone. The issue is that the changes caused to the planet over a couple of hundred years by man have more in common with the Cretaceous Palegene exinction event (the meteorite that killed the dinosaurs) than with the Paleocene Eocene Thermal Maximum (PETM) over 20,000 years - as described in this film. We are killing life before it can adapt and evolve.

[@MICKEYISLOWD]

@@ModernGentleman Wow.. how arrogant are you and ignorant. We are damaging this planet in one of the worst ways possible. We are now in the Earth's 6th mass extinction event and it is taking place 100 times faster than a natural event. The last time Co2 levels were this high was about 50 million yrs ago and sea levels were 7 mtrs higher than now. The ice is already melting due to the human made Co2 levels and it is all happening faster than anyone anticipated. The Earth is now flipping into it's new equilibrium and that is devastating for humans. We already lost 19% food production in just the last 5 yrs and this is going to continue eventually affecting the wealthy west. Mass migration has already begun and this means millions of people will head to Europe and Europe cannot support millions of people. Migration leads to conflict and already this has begun with most of Europe is turning far right! Try getting the facts together before you spout your beliefs because beliefs are 50% wrong yet facts are 100% true.

[@twinkletoes3010]

@@MICKEYISLOWD ur facts r a little off 2. Earth does not make a perfect circle around the sun. More egg like. This has been going on since earth was created. Just look at the ice cores. This is nothing unusual. If u quit cutting trees down. Which breath CO2. This would not happen as fast. But. It's still gonna happen.

[@sue08401]

So I should start to build up the number of my Turtle soup recipes and buy some beach property on the Arctic?

[@Michael-be7uw]

I'm just happy PBS is still educating us LOL

[@jillian2851]

Don't you mean BRAIN-WASHING?

[@Michael-be7uw]

@@jillian2851 LoL 😊😊

[@tragically.rachel]

It sure would be beneficial for us today to figure out how the PETM ended!

[@doctom7617]

Many of those deserted farms in the Alpine valleys may become productive again.

[@camputee1]

What they don't seem to want to say is that about 20 million years ago india crashed into asia and raised both the tibetan plateau and the thirty thousand foot high himilayas. The huge amounts of weathering that happened as a result of this efficiently scrubbed the excess co2 from the atmosphere and has led to the ten and twenty thousand year cycles of glaciation.

[@drmattbarnes1371]

Shhhhh, this is not a place for science!

[@RobertOlufs]

our oceans can absorb CO2 as well, matter of fact it is how most of our CO2 gets absorbed. Most of this stuff I have lived through these periods and we were studying ocean temperatures since 1980. The CO2 emissions are not accurate, unless he measured them over a volcano, and that would just be sad.

[@camputee1]

@Andrew Goering . Well I think it is a term that loosely applied means the action of wind and water. Freezing and thawing which degrades rocks and breaks them down, both chemically and physically.

[@electrictroy2010]

I don’t see how a small chain of mountains could affect the whole globe? Naturally the weather is affected in Southern Asia, but causing worldwide cooling/glaciation? Very Unlikely .

[@elLooto]

@@electrictroy2010 exposed rock absorbs CO2. A lot of CO2. the climate change scientists are in agreement that this happens. theres a good (pro-cc) vid done by the guy that collated the geological data.

[@Misterlikeseverythin]

World warmed more than any of us have ever seen. *So far*

[@ericbollinger9321]

I love your content, I was wondering about early earth when the moon was close, 3 kilometer tides racing around the planet

[@celticlass8573]

That would be something to see!

[@w.reidripley1968]

Don't think it was ever that close in, even in the Archaean.

[@Someone-sl4zq]

Did the PETM burn holes in the ozone layer (probably) and if it did how did it repair? Increase in plant population?

[@maxdesancha6025]

Ozone is produced naturally in the atmosphere, by oxygen interacting with UV light, so recovers on its own.

[@cstcomputers]

Moral of the story, the Earth didn't end but actually got better, and the idea that we can change that is preposterous.

[@roargathor]

Go home, you're drunk.

[@dennisvance4004]

roargathor so the earth didn’t end when it got hotter than it is now? How terrible that we had rain forests all around the earth and tropical jungles at the poles.

[@n.l.g.6401]

I wonder how those hot tub oceans affected storm formation. More convection = more power, but with a more uniform global temperature, would you even get enough atmospheric/ocean current mixing to stir things up? Someone better at meteorology pls explain.

[@JoshuaHillerup]

N. L. G. From my understanding there would be less powerful storms, that hold a lot more water.

[@superchuck3259]

The entire story being told, well it is just a story. It can not have happened that way. Plants do not grow in the dark. Poles are pretty dark in winter. If that even exists in the story.

[@superchuck3259]

Well the current Weather Channel "media/scientists" have specials stating the Global Warming will cause more intense hurricanes. So clearly if sea surface temps are primary fact in hurricanes, then yes they will be more powerful. My background is more extensive than the weather channel, read below for a deeper dive. It is truly amazing how water makes our world inhabitable. Scientific fact that airs ability to hold water vapor is not linear. So hotter temps hold way more water than cold temps. The cold poles of the world are basically deserts, but cold. When it comes to precipitation, the focus should be on precipitable water vapor. In the summer, with heat and humidity waves, the air can contain upwards of 4% water vapor by volume, we call this a muggy day. The watervapor is fuel for storage because when water vapor condenses then latent heat is released. When Air rises and the temp declines to the dew point, then the condensing water vapor heats the air from the latent heat of condensation of water (water going from gas to liquid) thus causing the temperature drop in air when it rises to no longer cool at dry adiabatic lapse rate but instead at this wet one. The air rises so long as it is warmer than the surrounding air and/or there is momentum for it to rise. See I had to explain and explain cause while there are generalities, there are so many variables, it can complicate things. Heck storm chasers have seen setups that looked like mega storms just turn into huge area of just weak rain showers that day. Here are the main influencer in climate: #1 Sunlight and that light actually reaching the ground (not reflected by clouds or dust like from volcanoes or worse) #2 Water Vapor - Primary greenhouse gas forcing warming of tens of degrees next warming #3 Thickness of atmosphere making the surface temperature livable. See at 35,000 feet the temp varies, but it is normally at or below freezing. While on the ground it could be 70 degrees F. If you look at Venus, the surface temperature is so high, not due to the sun, heck light doesn't even reach the surface, but instead due to the extreme pressure. The air gets compressed from the dry adiabatic lapse rate and by the time it is at the surface it is scorchingly hot. Sources for a deep dive into the numbers. web.gccaz.edu/~lnewman/gph111/topic_units/labs_all/water%20vapor%20capacity%20of%20air.pdf climateconsensarian.blogspot.com/2016/03/lapse-rate-on-venus-part-1.html Then just search for info on lapse rate. You will either like this stuff and dig deeper and realize it is complex or you will move on. Your call!

[@freethinker4liberty]

It is well documented that global cooling causes far more extreme global weather events, and global warming calms things down, even if that seem counter intuitive for a bit you seem to know why it's not :)

[@douglasdimwitty-zs9gx]

Depends on who you're listening to but the Australians are saying we're going the opposite direction and entering a ice age no one knows for sure, but one thing is certain the poles are drifting and the equator has changed. No one talks about that.

[@mcgritty8842]

Yall had polar bears show up on pieces of ice in Australia just how many years ago? Ice age just sounds moronic when you’re seeing the opposite happen

[@douglasdimwitty-zs9gx]

@@mcgritty8842 the earth is doing just fine, don't buy into the bull$4!+

[@robbyrobrob1]

We are all going to die. I already knew that.

[@aquaticterrafirma]

I think the point here is we are already dead.

[@Ginx-pe4si]

Live a hedonistic life. Dont have children because there are so many degenerates having them for everyone else.

[@tompain2751]

@@aquaticterrafirma ...eventually

[@grumpy4577]

Spoiler alert.

[@Puddlesmolly]

Fantastic

[@riverraging9462]

so orbits, distance from the sun, inclination, declination, none of this had anything to do with what happened?

[@forsakenquery]

@@ignaciom8906 err, 4000 / 5 = 800, not 200. Seems fine to me.

[@agreetodisagree4751]

@@forsakenquery To that endpoint. It will be affecting us looooong before we reach that endpoint.

[@lrvogt1257]

All of it influences what happens... including industrial GHGs. Knowing the natural patterns helps inform us that this current warming is not natural but artificially induced by industrial emissions.

[@drtlfletcher]

The impact of the Milankovitch cycles (eccentricity, obliquity, and precession) have a relatively small impact in isolation, which is why they were originally dismissed as important. Their influence comes from kickstarting feedback processes that massively amplify the original signal.

[@hisxmark]

Warm oceans release dissolved CO2 and the forams die off and quit taking it out of the ocean. The released CO2 and higher temperatures stimulate rain forests. But the warmer atmosphere expands and holds more H2O and the vapor rising to higher increases cloud cover and precipitation. Albedo goes down, ocean staying constant but the clouds condensing over the continents reflect more heat back into space. Decreased solar insolation reduces the health of the rain forests, and the temperature which has been forced to an extreme now rebounds vigorously causing dramatic cooling. The oscillation, as one might expect will reverse direction from more extreme conditions. Add sensitivity to initial conditions and the long term predictions become ... uncertain. We can't be certain of the balance between positive and negative feed backs, but we can be certain that there will be extremely swift and extreme fluctuations.

[@chromicm6686]

@Richard Conner and?... maybe we should not be living on top low lying ancient coral reefs then, there is a reason the bedrock there is limestone, it recently used to be shallow warm seaway, so why are we shocked when they are predicted to flood? If humans had never evolved on earth the current warming trend would occur regardless just as it has in the past interglacial cycles.

[@tonyhogan2000]

The last time the Planet warmed it ended the Ice age

[@redtiger2009]

In a million years will new intelligent life form re discover the internet and find our comments .....

[@SirNikurasu]

*B I G C H U N G U S*

[@julieannmyers8714]

You know "the cloud" is not an actual cloud, right? Somehow the server farms will survive??? Ok.

[@playdust3226]

They could find remnants of our space crafts left floating in space or rovers on the moon. but I doubt anything down here will last not unless its as big as the pyramids, or something buried deep down.

[@TassieLorenzo]

No. You need to carve stuff into stone and provide a way to translate the language.

[@85Funkadelic]

No it will all be lost sorry.

[@stevezelev7008]

It's amazing to me how little attention is paid to the influence of the SUN. It's that large plasma ball 330,000 larger than the 3rd stone from it that passes over head every day.

[@patrick1532]

What do you mean how little attention is paid to it? Do you understand the function of the greenhouse effect? Greenhouse gases absorb heat energy from the sun that would otherwise radiate out from the planet and trap it, preventing it from escaping, and causing the earth to warm. It's that simple. Of course we're paying attention to the sun.

[@Vision33r]

Once upon a time Egypt and Sahara was fertile with water, forests, trees. The climate on the planet always changes.

[@sirrathersplendid4825]

Vision33r - Was quite pleasant in the Sahara not that long ago. Lots of animal life there just a few thousand years BC.

[@Vision33r]

@@sirrathersplendid4825 Our course this is due to on-going climate change slowly or drastically. The ancient Egyptian texts also mentions about being near bodies of water.

[@tecumsehcristero]

I wish Chicago, New York and Philadelphia were tropical right now.