JoNova

A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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Egypt went from wetter to drier three times in Predynastic times with perfect CO2 levels

Back when CO2 levels were ideal, and there were 1 billion less cars than today, monsoons always happened in the same place, the rain was the same year after year, and there were no local extinctions of animals.

If we could only return to renewable slave power:

[ScienceDaily] The researchers identified five episodes over the past 6,000 years when dramatic changes occurred in Egypt’s mammalian community, three of which coincided with extreme environmental changes as the climate shifted to more arid conditions. These drying periods also coincided with upheaval in human societies, such as the collapse of the Old Kingdom around 4,000 years ago and the fall of the New Kingdom about 3,000 years ago.

“There were three large pulses of aridification as Egypt went from a wetter to a drier climate, starting with the end of the African Humid Period 5,500 years ago when the monsoons shifted to the south,” Yeakel said. “At the same time, human population densities were increasing, and competition for space along the Nile Valley would have had a large impact on animal populations.”

No climate models were harmed in the production of this paper.

(It’s not like they have anything to say about major climate shifts during times of CO2-sameness.)

6,000 years ago there were a lot of different mammals in Egypt:

Around six millennia ago, there were 37 species of large-bodied mammals in Egypt, but only eight species remain today. Among the species recorded in artwork from the late Predynastic Period (before 3100 BC) but no longer found in Egypt are lions, wild dogs, elephants, oryx, hartebeest, and giraffe.

What is an environmentalist to do? Evidently people without cars, factory assembly lines, oil rigs, and x-boxes can cause local extinction and shifts in climate patterns. (Who can deny that humans were “in upheaval” at the same time that the climate changed?)

University of Santa Cruz Press release had a different emphasis.

REFERENCES

Justin D. Yeakel, et al (2014). Collapse of an ecological network in Ancient Egypt. PNAS, September 8,. DOI: 10.1073/pnas.1408471111

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Egypt went from wetter to drier three times in Predynastic times with perfect CO2 levels , 8.7 out of 10 based on 65 ratings

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33 comments to Egypt went from wetter to drier three times in Predynastic times with perfect CO2 levels

  • #
    StefanL

    But, but … the laws of physics & chemistry were different then.
    It’s unfair of you to expect today’s post-modern climate models to explain these ancient events.

    240

    • #
      Ceetee

      Post modernism is a very large ugly and noisy device used for the shifting of goalposts by crap football teams.

      110

  • #
    Yonniestone

    With the ancient Egyptians eventually recognizing Ra (sun god) as a major influence around 2400BC it would seem they had enough sense to realize that the big orange fireball in the sky went a long way in affecting their lives rather than those evil polluting SUV camels.

    Going by the timeline above we should come to our senses around 5000AD, but don’t hold me to this until I consult my IPCC AMUN polar bear entrails.

    230

    • #
      Graeme No.3

      The ancient Egyptians were ahead of us in another area. When those in charge built giant and very expensive monuments the ancient Egyptians placed them under the monument.

      Hmmm!

      60

  • #
    Gee Aye

    Not just North Africa but Europe with the faunal distributions differing considerably from today. Tigers were not common knowledge in ancient European records – and for that matter later Roman times- because europeans travelled to the Far East to collect tigers. They were close and present. Then again there is another overlapping story that involves mass killing of tigers (an exemplar for many others), over many thousands of years in the region.

    The lesson is that the presence of particular mammals was not just a consequence of the climate.

    22

  • #
    Lawrie Ayres

    Just goes to show that history is another subject that should be taught along with maths and science. According to climate science the world starts about 1860 although BoM believes it is 1910. Anything before those times is mythology and obviously any written history is a work of fiction and totally unreliable. BTW those geologists who deal in rocks and strata also make stuff up and can’t possibly shed light on climate which is truly the purview of enlightened men and women who are the modern manifestation of Druids.

    200

  • #
    thingadonta

    Back then they blamed the rain and sun gods which were angry at the people’s behaviour, but now they blame…..the rain and sun gods which are angry at the people’s behaviour.

    260

  • #
    Olaf Koenders

    I’d say that another constant was malaria, regardless of CO2.

    40

  • #
    Blackadderthe4th

    ‘Eqypt went from wetter to drier three times in Predynastic times’ and the Sahara was a vast lush area of green. but then came along climate change

    How Earth’s Orbit Shaped the Sahara

    ‘The Sahara, the world’s largest desert, was once fertile grassland. This fact has been common knowledge in the scientific community for some time…The widely-held belief is that the Sahara dried up due to a change in the Earth’s orbit…the changes in the Earth’s orbital tilt and precession (or the wobbling motion) [which we know is not a factor in present climate change] occur because of gravitational forces emanating from other bodies in the solar system. To understand exactly what happens, picture a spinning top when it is slightly disturbed. Just like a top, the Earth too wobbles slightly about its rotational axis. This tilt changes between roughly 22 and 25 degrees about every 41,000 years, while the precession varies on about a 26,000-year period. These cycles have been determined by astronomers and validated by geologists studying ocean sediment records.’

    http://www.space.com/10527-earth-orbit-shaped-sahara.html

    Therefore the climate depends on more factors than just co2, but at present it is the only forcing factor!

    318

    • #
      The Backslider

      We are talking about a 6,000 year period, can’t you read?

      Therefore the climate depends on more factors than just co2, but at present it is the only forcing factor!

      Thanks for the laugh! Ha ha ha ha ha ha ha…..

      Don’t you know that AGW/CO2 theory depends almost entirely upon a “forcing” from increased water vapor? Shame that atmospheric water vapor has been falling, huh? The theory has been falsified by its own tenets.

      111

      • #
        Blackadderthe4th

        ‘ almost entirely upon a “forcing” from increased water vapor?’ oh no it doesn’t! As can be seen here.

        Water vapour and co2 as GHGs and heat vent blockers. [Therefore resulting in AGW! Except WV is negligible compared to co2].

        ‘70 years ago the view that co2 could affect the global climate was held by only a tiny minority of climate scientists, many assumed there would be a self regulating mechanism that would put things back into balance. Then there was the scientifically valid view that water vapour also trapped radiation and warms up the Earth and it is more abundant in the atmosphere than co2. But research in the 1940s changed all that, Guy Stewart Callender, a British engineer showed that radiation absorption is not even. Water vapour absorbs is mainly in the 18-30 micro-meter band and allows most of the rest to escape into space, in effect these absorption gaps act like cooling vents , but co2 absorbs in a different range, 8-18 micro-metre so Callender concluded that co2 mops up this escaping radiation, effectively acting as a plug to these cooling vents’. Potholer54.

        As you can see here!

        http://www.youtube.com/watch?v=_RdAKIN6Y6k

        116

        • #
          John in Oz

          ‘70 years ago the view that co2 could affect the global climate was held by only a tiny minority of climate scientists

          So the concensus then was the opposite to the current concensus.

          What’s a believer to believe???

          20

  • #
    Rolf

    Now there is a new, “worse than we thought”, “We are running out of time”, article at the ABC. This time the author is from the WMO. Kind of the usual stuff and of course comments closed. Has to stand without any say to not be broken down with pure facts.

    60

  • #
    Peter C

    Climate change in Egypt is recorded in the Old Testament.

    Genesis 41:53:53: “When the seven years of plenty which had been in the land of Egypt came to an end, the seven years of famine began to come, just as Joseph had said, “

    130

  • #
    Neville

    Err … Jo … “eGypt?
    LOL Cheers!


    Lol indeed. WordPress have no spellchecker on the headlines, and some fonts do funny “g’s”. Thanks. – Jo

    50

  • #
    john robertson

    There is no history but that which is sanctioned by the Grand Master!
    Slavery sounds like an excellent retribution.
    If a person insists that our modern energy intensive technology is evil.
    That oil,gas,coal and nuclear are too dangerous to tolerate.
    That hydroelectric damns the free spirit of the waterways.
    In other words the standard spell of our water melons.

    Slavery is the solution to this mental illness, the obscene desire to run other peoples lives for them.
    As the windmill and solar panels cannot provide reliable consistent power, we need a back up acceptable to the madness of the eco-nasties.
    The human hamster wheel.
    Scaled up to allow gangs of 10 or more, chanting their praises to their mother earth goddess, these eco-zombies shall be encouraged to run on the wheel of power, generating what? 40 Watts per person on average, so many wheels would need to be linked in unison.

    I am thinking individual person wheels on a common axle, with clutching to allow slave change , without shutting down the generator.
    Now with proper PR, propaganda the eco-concious would be lining up to donate an hour of power.
    We would only need about 750 wheels to equal one 30 Kw genet but we obviously have so many useless eaters.
    See its a social cohesion scheme, anti obesity plan, public worship and a load of smelly gym socks all in one.

    100

  • #
    john robertson

    Preview…Too early in morning here.
    Standard speal of our watermelons.That obscene desire..

    30

  • #
    peter horne

    A pedant writes…
    Fewer cars, darling girl, not less…

    40

  • #
    Roy Hogue

    I’m simply going to be grateful that the Egyptian people had the collective wisdom to overthrow the Muslim Brotherhood and hope they can keep that buch out while they build their new nation.

    Thank you, Egypt!

    And thank you for the help in dealing with Hamas.!

    90

  • #
    Roy Hogue

    A lot of things have changed over the past millennia. The Jordan River once emptied into the Red Sea. Now it dead ends in the Dead Sea at over 400 meters below sea level (nearly 1,300 feet).

    The Earth is not constant and many things affect the climate in any given region. I wonder how the Dead Sea has affected climate or whether it had any impact at all as the Jordan River valley sank into the ground.

    How significant is climate change compared to this rearrangement of the landscape? So large a body of water with its constant evaporation might just change something at least a little.

    60

  • #
    Safetyguy66

    It was most likely Moses messing with the climate again.

    30

    • #
      Roy Hogue

      Moses messed with the Pharaoh, not the climate. A pretty good job too. Pharaoh’s army is still at the bottom of the Red Sea by all accounts. ;-)

      00

  • #
    KinkyKeith

    This “new” info about species extinction just underlines the basic issue at hand.

    The world is a very big and dynamic place and the fact that some people claim it is possible to have a realistic scientific model of it is absolutely farcical to those of us who understand what modeling is about.

    It is a scientific impossibility to create a model which links Human Origin CO2 variations with Earth’s Climate.

    The fact that people claim to have made such models is an indictment of our present politicised science.

    If the effect of human origin CO2 was actually graphed it would simply be a FLAT-LINER ; no measurable effect.

    Meantime, the biggest danger to life on Earth lies just a few kilometers above us; interplanetary and intergalactic space.

    This huge heat sink is sitting there waiting to draw any heat we cannot hold onto into its gigantic belly.

    This heat sink has an unlimited capacity for energy and sits at a temperature of about 1.6 C degrees above Absolute Zero ie. minus 271.56 deg C.

    The temperature gradient from Earths surface is a staggering delta of about 290 C deg over say 40 kilometres.

    Our biggest problem is holding on to any energy we get from the Sun and any energy which leaks from the core of our Planet to the surface.

    The current debate about Global Warming is not science, but human nature works best with Group Think, it is so very comforting, even as we chase the wrong problem and risk having our children freeze to death not to far in the future.

    KK

    50

  • #
    Richard Hill

    It would be good if more was done to study paleodrought in Australia.
    As well as Africa, it is accepted that there were long droughts in North America, not so long ago. Up to 200yrs I think.
    Yet AFAIK no work is done on continental Australia.
    Temperature is the big focus, not rainfall. I am sure the people in far western Queensland would readliy accept a couple of degrees extra temp if they got rain.
    What are the research priorities for people like M. England and D. Karoly?

    50

    • #

      Yes Richard, there is a strange absence of paleo-proxies in Australia. You would think someone could find a clam shell, bit of coral, lake sediment or stalagmite.

      And since we have homogenized thermometers no one seems at all interested in proxies after 1980 either…

      You would swear there was a rush not to look for evidence.

      80

      • #
        Ken Stewart

        Coral in Qld reefs?

        00

      • #
        DonS

        Yes Jo, but there is not a lot of funding for “someone” to do palaeontological exploration in Australia. Certainly not when compared to funding for climate research. Another example of one area of science being under funded so that others can chase carbon fairies around the garden?
        It also depends on which time period you are interested in. The palaeo record of Australia is not complete from the year dot to now. Also unlike some Palaeontologists I don’t think that a clam shell, a bit of coral or a stalagmite is evidence from which to make wide reaching conclusions. I like to see lots of samples from lots of places. For example, the evidence for Tim Flannery’s widely accepted hypothesis that Aborigines ate the mega fauna to extinction consists of 1 bone fragment that may have been in a campfire. Not really solid evidence, and I would say not really science.

        10

    • #
      James Murphy

      It’s hardly ‘old’, but South Australia (at least) has a few towns, like Farina which were settled in the 1880s with the hope of being major wheat/barley areas, and subsequently went bust because they stopped getting enough rain to be viable. In the same state, during the 1860s, George Goyder used his eyes, and his brain to decide where crops could, and couldn’t be grown reliably – based chiefly on a change in vegetation type. Anything on the ‘wrong’ side of Goyders line was, in his opinion doomed to fail, or at least not receive enough regular rainfall. If Farina is anything to go by, people obviously didn’t listen to sound advice back then, either.

      However, it’s after the start of the industrial revolution, so I guess AGW was to blame for the failures, rather than people choosing to ignore someone with keen observational skills, and excellent deductive logic…

      40

  • #
    DonS

    “Around six millennia ago, there were 37 species of large-bodied mammals in Egypt, but only eight species remain today.”

    By “today” do they mean 2014 or just modern times in general?

    Just a note of caution on disappearance of large bodied mammals from Egypt and North Africa in general.

    As I understand it the Roman Empire had an insatiable demand for exotic African animals for use in their various entertainments. There was a massive industry based around the capture and export of these animals to Roman cities across the Empire.

    While the drying climate no doubt led to changes in the fauna of North Africa we can not ignore the role the Romans played in the disappearances. Lions, Elephants, Giraffes etc. were all top of pops for the Roman entertainment industry.

    10