17 ms·
Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature a
by sgirard 3y ago
Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature above Greenland was 5°C warmer than today."
- robertlagrant 3y ago[flagged]
- WhitneyLand 3y agoI’m not aware of any data that supports humans 120k years ago having a significant impact on the earths climate. I think even our ability to start fire at will is conclusively known to be only ~50,000 years ago.
- hutzlibu 3y ago"Claims for the earliest definitive evidence of control of fire by a member of Homo range from 1.7 to 2.0 million years ago " https://en.m.wikipedia.org/wiki/Control_of_fire_by_early_humans https://en.m.wikipedia.org/wiki/Control_of_fire_by_early_hum... You don't need to be able to start a fire, when you keep the fire burning all the time. And you can do that, once you control the fire and figure out the difference between dry and wet wood. Also humans are the dominating species on land since quite a while. Hunting certain species to extinctiom has certain effects on the local ecosystem and globally on the global climate. It all adds up. But things surely changed in dimension since industrialisation.
- dekhn 3y agoPeople had fire in those times but it's extremely unlikely they produced enough CO2 to have an anthropogenic impact on the climate leading to large-scale temperature changes. I'm not sure what your perspective on this situation is but I think the case for modern anthropogenic climate change with deleterious effects is based on a wide range of different evidence, and a careful accumulation of facts and analysis. Simply pointing out that humans had fire 2Mya doesn't change the general conclusion about today.
- londons_explore 3y agoI suspect gr main change caused by humans >100 k years ago will be wiping out various species and starting fires in seasons and places where fires wouldn't normally start (eg. In places without dry lightning or volcanoes - the only two other ways fires naturally start)
- detourdog 3y agoI always wonder about that natural fission reactor in Gabon. They discovered the Uranium was pre depleted in particular mines. https://en.wikipedia.org/wiki/Oklo_Mine https://en.wikipedia.org/wiki/Oklo_Mine Fun to imagine the possibilities.
- angiosperm 3y agoThat was more than a billion years ago, so no.
- detourdog 3y agoI’ll take a risk and be skeptical of that claim and see how my life turns out.
- angiosperm 3y agoMaybe consult the very first paragraph of the article you cited.
- detourdog 3y agoI read it but I didn't take it as proof. A team of people when faced with a mystery and the came up with an answer. They is not the same as proof in my book. I also did poorly in school. I'm not good at taking this as stated. I enjoy wallowing in the unknown rather than believe everything I'm told to me own detriment.
- angiosperm 3y agoA wikipedia article does not pretend to be proof. It is a summary. For proof you would need to look at the, y'know, evidence. The decay rates of the isotopes involved are known exactly. It is hard to find anything more certain than timelines revealed by radioactive decay.
- 3y ago
- gameman144 3y agoJust in case this is just a case of word confusion (which I've had before), "anthropogenic" means "caused by humans", not "occurring at the same time as humans".
- newfonewhodis 3y agoI'm not a scientist so I'm curious why this is interesting.
- p1esk 3y agoPresumably because we can find well preserved organisms from that time.
- downWidOutaFite 3y agoIt's not scientifically interesting, the glacial-interglacial cycles are pretty well established. I'm guessing they're trying to insinuate some climate change minimalism argument.
- mensetmanusman 3y agoIt’s interesting to know how far back in time the ice will allow them to analyze once they get to the base.
- deleted 3y ago[deleted]
- snowwrestler 3y agoI think people who are not already familiar with the known history of the Earth find it interesting that there have been higher CO2 levels and temps than there are now. And I agree: the history of the Earth is interesting. Which is why so many people study and work in the field of geology.
- rolph 3y agothe drilling allows sampling of environmental components over extended period of time. this meas a historic record of, gases, ash, soot, pollen, spores, silt, insects, plant animals, metals, salts.....
- detourdog 3y agoIt's interesting because the whole ice cap as we know it is around 120k years ago which I don't consider the long ago on human development scale. This also appears to mean that in the past 120K there wasn't a polar ice cap. I read that as the worst case scenario we should be using for long term planning. This also may help determine how fast the ice was built and how fast it will melt. I'm completely an armchair ponderer.
- deleted 3y ago[deleted]
- monero-xmr 3y ago[flagged]
- spockz 3y agoAlthough indeed the temperatures and GHG have been lower and higher on Earth before, that was never with the amount of humans we have now. Our economy and society is quite optimised and our infrastructure hubs are largely located on coasts. Our prosperity also relies on a large amount of sophisticated technology that is hard to replace and to bootstrap. So although the human species will probably survive a drastic climate change, many individuals will not due to famine, lack of medical supplies and care, and war over the remaining resources.
- hnhg 3y agoIt is also because it will result in incredible levels of migration and competition for resources in the short term (ie wars). Yes, humanity will survive but it might make global shocks like the pandemic seem very tepid by comparison.
- shostack 3y agoThe earth may have survived those changes, but not all its inhabitants may have. So there definitely is still reason to worry as far as humanity is concerned. The major ecological shifts may bring change humanity does not bounce back from.
- notfish 3y agoWhen the cause for optimism is “some humans will probably survive”, I don’t feel very optimistic
- FrustratedMonky 3y ago>>"The doomsday cult saying we are all going to die, or that every single heat wave and natural disaster can be pinned on extra carbon, are just yet another in a long line of apocalyptic predictors" The problem with this argument is that 'humans' surviving, is different than 'our nice comfortable human society' surviving. Yes, the human species as an animal that can survive by foraging, probably will survive. That isn't a great argument.
- adolph 3y ago120k years ago in context: * 170,000 years ago: humans are wearing clothing by this date. * 125,000 years ago: the peak of the Eemian interglacial period. * ~120,000 years ago: possibly the earliest evidence of use of symbols etched onto bone * 75,000 years ago: Toba Volcano supereruption that may have contributed to human populations being lowered to about 15,000 people https://en.wikipedia.org/wiki/Timeline_of_prehistory https://en.wikipedia.org/wiki/Timeline_of_prehistory The Eemian climate is believed to have been warmer than the current Holocene. Changes in the Earth's orbital parameters from today (greater obliquity and eccentricity, and perihelion), known as Milankovitch cycles, probably led to greater seasonal temperature variations in the Northern Hemisphere. During the northern summer, temperatures in the Arctic region were about 2-4 °C higher than in 2011. The hippopotamus was distributed as far north as the rivers Rhine and Thames. . . . The prairie-forest boundary in the Great Plains of the United States lay further west near Lubbock, Texas, whereas the current boundary is near Dallas. . . . Sea level at peak was probably 6 to 9 metres (20 to 30 feet) higher than today . . . . https://en.wikipedia.org/wiki/Eemian https://en.wikipedia.org/wiki/Eemian
- orangepurple 3y agoThis raises a very critical point. Nuclear is the only dependable energy source. Fossil fuels will run out or go out of favor. Solar and wind on the other hand will become victims of the next major volcanic eruption as ash destroys them or renders them ineffective.
- ricardobeat 3y agoNuclear facilities seem pretty fragile / demanding, I doubt one would survive any kind of apocalyptic event. The infrastructure supporting it will be gone.
- fullstackchris 3y agoisnt that the case with any advanced technology? (including wind and solar)
- mytailorisrich 3y agoIirc, the CO2 concentration now as been pumped up higher than it was then, which is in part what is worrying because temps might then potentially shoot even higher. Bottom line: we need large scale carbon capture quickly because even if we reach net zero CO2 will take millenia to drop back to the level it was pre-industrial revolution. Edit: I wouldn't focus on "pre-industrial levels" specifically, the point is that there is too much now so we most likely want concentration to drop as soon as possible.
- elzbardico 3y agoWhy do we need to get back to the levels pre-industrial revolution?
- mytailorisrich 3y agoThe point is that net zero is most likely not going to stop warming with 400+ppm CO2 in the atmosphere. CO2 concentration most likely has to drop but naturally it does so very slowly. Arguably at this point we already need cooling because 40+C every summer in half of Europe (for instance) is getting annoying...
- gottorf 3y ago> at this point we already need cooling A colossal volcanic eruption could do the trick, and those seem to happen rather unnervingly frequently.
- MichaelZuo 3y agoYeah it would be pretty silly for humanity to invest so much time and effort into lowering CO2 levels only for a Yellowstone or equivalent to erupt and send temperatures plummeting into a new ice age levels. When if humanity did nothing the eruption would only have taken us back to pre-industrial age temperatures.
- sleet_spotter 3y ago
- thomasahle 3y agoSee also this timeline of the last four inter-glacial periods: https://co2coalition.org/wp-content/uploads/2021/09/104-400000-years-of-temp.jpg https://co2coalition.org/wp-content/uploads/2021/09/104-4000... It also shows how crazy it would be if we get the projected 2-3 degrees average temperature increase. Even in a period where we'd expect to be going into a new ice age; instead shooting to a previously unseen high temperature.
- slashdev 3y agoOn the other hand if we only have 2-3 degrees of warming, if that’s enough to prevent the next ice age, didn’t we just dodge a massive icy bullet? Might we not one day thank ourselves for doing something reckless and stupid that actually worked out? Yeah a warmer climate brings all kinds of horrible changes. But food still grows in the northern hemisphere. A colder climate is arguably even worse for us. By the way, that’s no excuse to keep doing what we’re doing. Limiting warning at 2-3 degrees will be nice. Things get really horrific above 4. At some unknown point feedback cycles really kick in and we go to 5-10 degrees and get completely fucked. We really have to not find out where that threshold is.
- kuprel 3y agoI didn't realize that the vast majority of the time Earth is in an ice age. What causes it periodically like this?
- slashdev 3y agoIt’s mostly caused by Milankovitch cycles. Which are cyclic variations in our orbit around the sun. The earth varies in distance to the sun and axial tilt and precession. Like waves, there factors can either overlap and somewhat cancel or they can stack for a larger effect.
- autokad 3y agoice ages didn't happen until after the asteroid strike. Antarctica moving into the south pole is likely a large part of it, but they don't really understand ice ages that well TBO. Anyhoo, the Earth was a lot warmer prior to the strike and we have been going through extinction events every 100k years.