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The Sahara may flip from desert to grass every 20,000 years. Blame The Sun.

MIT researchers think they have solved a bit of a mystery regarding Sahara dust, but if they’re right it means the Sahara Desert has already come and gone 3 – 5 times since humans walked the Earth. The Sahara is the largest desert on Earth, and this would be the largest and longest drought “ever” on the planet (as far as we know).

UPDATED: Commenter Javier points out these drying cycles were known years ago. (See below)

This would rather redefine the whole idea of “climate change” — 3.5 million square miles of Green Sahara turns into Dust-bowl Sahara — and it’s all thanks to sunlight. The drought doesn’t just last 7 years, but more like 7,000. And it’s happening over 9 million square kilometers, an area larger than Australia. The major climate models leaned towards the monsoonal cycle, rather than the longer ice age one. So this theory may have resolved one of the 495 contradictions in climate models. Or not. But the bigger message here is that the sun causes climate change and on a massive scale.

h/t to Roger Tallbloke.

The Sahara is the largest dust bowl in the world, dumping 10 million trucks of dust across North Africa and the Atlantic Ocean. The dust can end up as far away as Florida. People tracked the layers of this dust before but thought the highs and lows were driven by ice-ages on a 100,000 year cycle. This new work took a closer look at the layers on the ocean and say they see 20,000 year cycles, which fit with cycles of solar insolation (meaning the strength of sunlight as the Earth rolls around on its axis). It sounds like a long bow figuring out whether there were trees and rain in the Sahara based on layers of dirt on the ocean floor, so keep our skeptical hats on. It could turn out to be wrong. But then again, they are looking at 240,000 years of mud and it fits better with other proxies too, so it has some redeeming features.

solar insolation,Graph, Saharan dust.

solar insolation,Graph, Saharan dust.

 

Monsoons vary with the solar insolation, as does the level of the Nile River and other stuff:

 This finding is consistent with a wide range of other monsoon proxies from North and East Africa that show high-amplitude precessional variability (Fig. 4). Sapropels in the eastern Mediterranean (Fig. 1), a marker of high Nile River discharge, occur during each of the dust flux minima in our record over the past 240 ka and show clear precessional pacing (Fig. 4) (28). Similarly, δD values in leaf waxes from the Gulf of Aden (Fig. 1), a tracer of monsoon intensity in East Africa (17), show strong similarities with our record (Fig. 4). Records of the accumulation of windblown freshwater diatoms in Tropical Atlantic sediments, a tracer of the desiccation of Saharan lakes at the end of wet periods, also show precessional variability with little power at 41- and 100-ka periods (18).

It always makes me suspicious when the researchers cite failed climate models as another reason to believe:

But McGee says this [older] interpretation of the sediment cores chafes against climate models, which show that Saharan climate should be driven by the region’s monsoon season, the strength of which is determined by the tilt of the Earth’s axis and the amount of sunlight that can fuel monsoons in the summer.

The researchers think previous teams missed the 20k cycle because some dust spikes were there for a different reason:

“What we found was that some of the peaks of dust in the cores were due to increases in dust deposition in the ocean, but other peaks were simply because of carbonate dissolution and the fact that during ice ages, in this region of the ocean, the ocean was more acidic and corrosive to calcium carbonate,” McGee says. “It might look like there’s more dust deposited in the ocean, when really, there isn’t.”

Wait — so cold ice-ages with low CO2 levels make that part of the ocean acidic? Seriously?

Is that the sound of another sacred cow dying?

 UPDATE: Javier points out that the 20,000 year cycle was reported 30 years ago

OK, this is anything but new. It has been known since the mid-1980′s that the Sahara greening and drying follows the 23 kyr precession cycle because precession-linked insolation sets the position of the Inter-Tropical Convergence Zone, the climatic equator that determines how far North the West-African Monsoon reaches.

Martine Rossignol-Strick worked out this relationship in 1985 in her article:
Rossignol-Strick, M. (1985). Mediterranean Quaternary sapropels, an immediate response of the African monsoon to variation of insolation. Palaeogeography, palaeoclimatology, palaeoecology, 49(3-4), 237-263.

In this article from 2012: Green Sahara: African Humid Periods Paced by Earth’s Orbital Changes, Nature, 2012

We can read:

“Longer stratigraphic sections extending as far back as the Miocene (Hilgen et al., 1995) contain hundreds of these sapropel layers, each representative of an earlier African humid phase and each paced by the characteristic orbital precession beat of 20,000 years (Figure 4). These sapropel layers are packaged into groups of 4–5 (Figure 4), reflecting the influence of slight changes in the shape of the Earth’s orbit around the sun (eccentricity) on modulating the strength of the precessional beat.”

I hate this press releases that make it look like they have discovered something new, when in reality they just got more evidence for what is already known.

MIT press release  |  Eureka Alert Press Release.  | Science Daily

REFERENCE

Skonieczvy, C, McGee, D, other people (2019) Science Advances  Vol. 5, no. 1, eaav1887 DOI: 10.1126/sciadv.aav1887

 

 

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118 comments to The Sahara may flip from desert to grass every 20,000 years. Blame The Sun.

  • #
    Mark M

    And so it goes …

    “Each year iron from Saharan dust clouds is deposited in the waters off the West Florida coast.

    Once there, plant-like bacteria use the iron to set the stage for red tides.

    When iron levels go up, this bacteria, called Trichodesmium, ‘fixes’ nitrogen in the water, converting it to a form usable by other marine life.

    The addition of biologically usable nitrogen in the water makes the Gulf of Mexico a more likely environment for toxic algae to bloom.”

    Dust from Africa Leads to Large Toxic Algae Blooms in Gulf of Mexico, Study Finds

    https://svs.gsfc.nasa.gov/stories/dust/

    110

  • #

    What? The sun affects our climate? Pull the other one!

    300

  • #
    el gordo

    The onset and termination of the African Humid Period is abrupt, in the sense that it may take place over a couple of centuries or perhaps even decades.

    There is a feeling that the insolation cycle is too gradual to bring about this startling transition and so its hypothesised that non-linear feedbacks may come into play, such as vegetation – atmosphere interactions.

    50

  • #
    el gordo

    ‘During the last glacial period, the Sahara was much larger than it is today, extending south beyond its current boundaries. The end of the glacial period brought more rain to the Sahara, from about 8000 BC to 6000 BC, perhaps because of low pressure areas over the collapsing ice sheets to the north.

    ‘Once the ice sheets were gone, the northern Sahara dried out. In the southern Sahara, the drying trend was initially counteracted by the monsoon, which brought rain further north than it does today. By around 4200 BC, however, the monsoon retreated south to approximately where it is today, leading to the gradual desertification of the Sahara. The Sahara is now as dry as it was about 13,000 years ago.’

    wiki

    101

    • #
      Alfred (Cairns)

      That is how the ancestors of the Ancient Egyptians were compelled to gravitate towards the Nile and to practise agriculture and irrigation.

      00

  • #
    David Maddison

    How did it come to be that what passes for “science” today has become so dumbed down that it is assumed that the natural state of the climate and sun is steady state? All this was well known until about 30 years ago.

    While he doesn’t talk specifically about the dumbing down of science, Victor Davis Hanson gives part of the answer in this 17 min 19 sec video on “The New Dark Age Mind”: https://youtu.be/O9IKHgWUnqw

    131

    • #
      David Maddison

      Even historians used to realise that climate was not steady state and that natural climate change contributed to, or was responsible for, the rise and fall of civilisations. That’s yet another reason they don’t teach real history any more.

      170

    • #
      David Maddison

      In #5 above I meant to say that what was well known until 30 years ago was that the climate and sun were NOT steady state. I think the rational readers here would have understood what I meant anyway.

      120

    • #

      Soon we will be hearing from eminent ‘scientists’ that the world is actually flat and supported by four elephants standing on the back of a turtle.

      90

  • #
    David Maddison

    Rational thinkers should be familiar with this concept advocated by the enemies of Western Civilisation.

    Degrowth.

    https://en.m.wikipedia.org/wiki/Degrowth

    51

    • #
      OriginalSteve

      “Marxist critique

      “Marxists distinguish between two types of growth: that which is useful to mankind, and that which simply exists to increase profits for companies. Marxists consider that it is the nature and control of production that is the determinant, and not the quantity. They believe that control and a strategy for growth are the pillars that enable social and economic development. According to Jean Zin, while the justification for degrowth is valid, it is not a solution to the problem.[49]

      However, other Marxist writers have adopted positions close to the de-growth perspective. For example, John Bellamy Foster[50] and Fred Magdoff,[51] in common with David Harvey, Immanuel Wallerstein, Paul Sweezy and others focus on endless capital accumulation as the basic principle and goal of capitalism. This is the source of economic growth and, in the view of these writers, is unsustainable. Foster and Magdoff develop Marx’s own concept of the metabolic rift, something he noted in the exhaustion of soils by capitalist systems of food production, though this is not unique to capitalist systems of food production as seen in the Aral Sea.”

      If you boil it all down, Marx was apparently funded by wealthy people to write his manifesto…..what the Elite learnt was that if you create a Thesis ( Capitalism ) and antithesis ( Communism ) you can then control the “struggle” that occurs between the two.

      We see this now with the fight between normal people who can better their lives through honest work and have something to pass onto their children ( Capitalism ) versus the Marxist tranb of thought that falsely assumes all humans are equal, and that govt can control & provide for all our needs.

      Interestingly, we also see a clash between Capitalism , which allows peoples private pursuit of religion and self protection, vs Communisms forced atheism and people at the complete mercy of the whims of the State.

      100

  • #
    el gordo

    We don’t have to wait for the cycle to return, humanity can turn deserts into lush environments within decades.

    http://www.chinadaily.com.cn/a/201808/06/WS5b678ab7a3100d951b8c8b07.html

    50

    • #
      David Maddison

      Frankly, Australia should be ashamed of the fact that so little has been done to irrigate our deserts. The billions wasted on desal plants and useless intermittent electricity production could and should have been spent on such projects. And just imagine what a few well-placed river diversions and also nuclear powered desal plants could have done. In fact, it has even been suggested that once Australia’s deserts were greened, natural rainfall would return.

      Of course, none of this will ever happen because Australians now lack vision and are also dominated by Leftists who believe in the doctrine of degrowth. Example: As reported here yesterday 2600 ha (6425 acres) of productive farmland is about to be removed from service to build a solar subsidy farm.

      320

      • #

        The problem with that is not being able to predict the unintended consequences. What would the overall effects on not just Australia’s weather patterns, but those elsewhere, if such a large land mass was suddenly fully greened?

        70

        • #
          David Maddison

          The interior of Australia being fully greened is not without precedent. It was thought to be fully greened naturally until about 10,000 years ago.

          90

          • #

            Even if it was, we don’t know how that affected the eastern seaboard, as an example, and how such greening would affect an area now significantly populated. Consider that cyclones (or hurricanes in the US vernacular) have always been about, strong or otherwise, but even a weak cyclone can now have a major effect on populated areas because populations and the supporting infrastructure is now so significant.

            70

          • #
            el gordo

            ‘It was thought to be fully greened naturally until about 10,000 years ago.’

            That is news to me, do you have a link?

            10

      • #
        el gordo

        ‘… so little has been done to irrigate our deserts.’

        There have been visionaries, yet there was never the political will or cash, but that is set to change.

        50

        • #
          Sambar

          ” There have been visionaries, yet there was never the political will or cash, but that is set to change”

          You are correct EG. under Chinese management things will be very different, and not necessarily better for the 184 different nationalities that make up native Australians

          110

        • #
          Robber

          To re-engineer Australia, we need to create a vast western mountain range and a north/south sea that separates WA from the rest. Consider an extensive series of underground nuclear explosions that both creates the sea and throws up the mountain range.

          40

      • #
        Binny Pegler

        It’s about economics. The biggest challenge to Australian Agriculture is an oversupply of food.
        (Among countries that can afford to pay prices in line with our expected standard of living)
        If the market (value) was there irrigation would be expanded.

        50

      • #
        Pauly

        David,
        Australia has three problems that you seem to ignore. The most obvious one is lack of consistent rainfall. In the USA, they consider 20” of rain per year as the minimum for good agricultural endeavours. Anything less is considered desert. But consistency is the critical factor. Otherwise, you have to store sufficient water to last out the normal drought periods.

        Which brings us to the second problem: lack of suitable locations for dams. Australia simply lacks much vertical relief. So to build a large water storage capacity, you need to inundate large amounts of land.

        And that leads to the third point: Australia generally has very little in the way of top soil. So most of Australia is simply infertile, and only becomes worse if irrigated. Dr Tim Ball recently discussed the importance of soils here: https://wattsupwiththat.com/2018/10/08/some-of-the-major-myths-about-vegetation-soil-and-climate/

        Of course, the CSIRO might know a bit more about this than you or I, but I guess that they are too busy focusing on climate change.

        100

    • #
      PeterS

      Yes we can turn our deserts into flouring environments. Others have done it. We just lack the will and the leadership to do it. Not to worry. China will probably do it for us once they take over. They can then build all the necessary dams, hydro, nuclear and coal fired power stations necessary. We are such fools we don’t even notice the golden opportunities we have missed over the decades. In effect we could have been a world power with our own leading space industry mining the asteroids by now if only… oh stuff it. I’m getting tired of talking to myself.

      133

      • #
        jeff

        China has a 145 people per square km, Australia has 3.
        Rich Chinese want to immigrate to Australia, not the other way round.
        Maybe a lot of Australians don’t want a high population density and a fully exploited environment.

        90

        • #
          PeterS

          I’m not advocating nor support high population density but it’s happening already in our major cities. If we allow it the Chinese will make it much worse. As for fully exploiting the environment that’s such a loaded term with mixed connotations I won’t even bother going there. Suffice to say if we don’t protect what we have and take advantage of it in a sensible and controlled way someone else will do it for us in a senseless and uncontrolled way, which has started already.

          50

          • #
            el gordo

            ‘If we allow it the Chinese will make it much worse.’

            They won’t if we have a strong centre right government holding the reins. Chinese investment has mucked up the capital cities, which is really sad, but there is no stopping this juggernaut.

            Beijing knows we have no money for major capital works and is prepared to lend at very reasonable rates to build our satellite cities, connected by a continental bullet train network, a water irrigation pipeline from the Ord, new dams along the way and an inland sea for recreation.

            A food bowl and theme park.

            31

            • #
              Sambar

              Like here in Victoriastan where the state government has borrowed Chinese money for the promised infrastucture programme, apparently without bothering to consult the federal government, and also the treasurer publicly declared that future generations will be resposable for repayments. Spend, spend , spend. A balanced ledger, living within our means, nah just an old fashioned idea.

              51

              • #
                el gordo

                Premier Gladys has got the message from the Victorian election, the people want bread and circuses. That is why she is floating very fast rail and intends getting Morrison to back her, a strategy which should see them both home comfortably.

                We tend to think of it as ‘funny money’, dodgy dealings, but in fact its the new capitalism and we have the capacity to pay back our loan.

                01

      • #
        el gordo

        ‘In effect we could have been a world power with our own leading space industry mining the asteroids by now if only…’

        China wants to build a space launching pad in Katter’s electorate on Cape York and I think we should do it.

        Importantly, our balance of trade with China may stay in our favour and we’ll have to let them build our infrastructure, like drought proofing Australia. We do business in US dollars, what could go wrong?

        https://product.datastream.com/dscharting/gateway.aspx?abcnewsembedheight=430&action=REFRESH&guid=91d324dc-0ca8-4764-b06d-f04668d8e926

        10

  • #
    David Maddison

    Do you think that any climate catastrophists know why Greenland was called as such?

    I note however that climate catastrophists, in keeping with their belief of a steady state climate are now claiming that Erik the Red calling the island by that name was a scheme to induce others to settle there, not the favourable climate of the time.

    80

    • #
      Robber

      Climate Change? The current landscape of the Kimberley has been evolving over a period of at least 250 million years. Periods of uplift resulted in peneplanation of the land surface and deeply incised rivers. A lengthy period of tropical conditions 70-50 million years ago resulted in the development of a lateritic cap, particularly over the volcanic rocks which are more susceptible to weathering. This is a characteristic feature of the Mitchell Plateau.

      As sea levels rose from approximately 120m below current levels following the end of the last glacial maxima 18,000 years ago, the Kimberley coast line became drowned with the sea filling what were once river valleys. This phenomena gives the coastline its distinctive irregular outline.

      During the Devonian period, a barrier reef system formed before a subsequent drop in sea levels over the Kimberley. This reef system was similar to the Great Barrier Reef and is still visible today in the form of the Napier Range and the Ningbing Range. The Devonian was a relatively warm period, and probably lacked any glaciers. The temperature gradient from the equator to the poles was not as large as it is today. The weather was also very arid, mostly along the equator where it was the driest. Reconstruction of tropical sea surface temperature from conodont apatite implies an average value of 30 °C in the Early Devonian. CO2 levels dropped steeply throughout the Devonian period as the burial of the newly evolved forests drew carbon out of the atmosphere into sediments; this may be reflected by a Mid-Devonian cooling of around 5 °C.

      30

    • #
      sophocles

      Do you think that any climate catastrophists know why Greenland was called as such?

      … only those who work as Real Estate agents … :-)

      60

    • #
      John F. Hultquist

      “why Greenland was called such”

      It is a small mind that can think of only one.
      Consider, every place from which folks came — was more green than Greenland.
      Try harder.

      20

  • #
    thingadonta

    One of the alarmist’s favorites is that the Sahara will get drier, yet most evidence -from the past and also more recent-points to it getting wetter when the climate warms. There is some recent evidence tis is occurring.

    http://news.bbc.co.uk/2/hi/africa/8150415.stm

    https://www.forbes.com/sites/jamestaylor/2012/10/25/contrary-to-what-you-hear-global-warming-has-been-good-to-africa/#3c1b932d27f6

    60

    • #
      jeff

      Yes, that is one of their standard claims – the Sahara desert is growing.
      They do say there will be more rainfall with warming, but that increased temperature will dry things out faster.
      But there are so many natural ways that water is stored for later use by plants.
      It’s like a farmer that has tanks and dams would generally prefer warmer temperatures if it also meant more frequent rain.

      40

    • #
      theRealUniverse

      The complete crap about warming is that it gets drier, exactly the opposite occurs it gets WETTER. More evaporation means more precipitation.
      The iceages were relatively dry periods.

      81

    • #
      Reed Coray

      Although Antarctica possesses more fresh water (in the form of ice) than any other continent, Antarctica’s atmosphere is both the driest (https://www.quora.com/Which-is-the-driest-continent-in-the-world) and the coldest continent on Earth. Taking a phrase from our beloved former Vice President, if true, anyone who believes in the theory that global warming will result in a drier Sahara Desert will have to address this inconvenient truth.

      60

  • #
    TdeF

    As I found in Egypt, our English language is full of foreign tautologies. ‘Sahara’ means desert in Arabic. Avon/afon means river in Welsh so the river Avon is a river river. The famous ‘Stari Most’ bridge in Mostar is odd because Most simply means bridge in Slavic languages like Russian, Polish, Bulgarian. This can get silly. In fact Stari simply means old. One place in England called ‘Torpenhow hill’ contains four word meaning hill. Tor, Pen, How and hill.

    So it is just the Sahara. An extraordinary place for which living in Australia does not prepare you, because it is real desert with absolutely zero humidity, not our ready to bloom landscape often fed by high humidity from the tropics. You really need to drink water all the time in the Sahara or Arabia. Australia’s deserts will bloom with the slighest drop of water. They have plenty of CO2 and sunshine and the seeds are there.

    What is odd is that while we recognize the sun is the generator of all life, the ultimate source of all heat and fossil fuels are only stored sunlight, there is this insistence that we humans now control the temperature of the planet through a mechanism untested and now thoroughly debunked. From ignorance to arrogance in the 20th century.

    It is generally accepted that CO2 is not enough to change planetary temperature without help from water, by far the major greenhouse gas. No other gas comes close. The idea that there was a runaway warming from creating more steam in the middle altitudes has proven to be false.

    So the whole man made Global Warming story has been disproven by accepted science. There is no explanation for the alleged warming. So is it true? As in the last post, there is every expectation that the idea of a tiny 0.5C in ten years warming is an artifact of an uncompensated instrumentation change. The subsequent 20 years have confirmed this as the ‘warming’ has stopped, so did it ever happen?

    The giant Green money laundering machine wants even more trillions. To save the planet apparently, but is any part of the story which is true? Not as far as anyone can tell. My question is whether Al Gore, Michael Mann, Tim Flannery, Hansen et al. actually believe this after thirty years of milking the story for prizes, even Nobel prizes, cash and fame and holiday houses on the seashore. I doubt it, but why stop now?

    You could also ask whether priests of any religion are convinced of the truth of their religion as they age? It’s probably too late for most of them to turn sceptic. I feel sorriest for all those with degrees in Global Warming/Climate Change who have to defend a religion without any factual basis, but that is true of most religions.

    Yes, we know so much about the past. The religion known as ‘The Science’ cannot fit the 20th century data, let alone the 21st. It’s all history now, except the laws which rip the dollars out of our electricity bills for gifts to anyone who produces green electrons, even if they do not sell them.

    150

    • #
      JoKaH

      our English language is full of foreign tautologies

      It doesn’t need to be foreign tautologies – we have our own home grown tautologies like “PIN numbers” and “ATM machines” etc.

      80

      • #
        TdeF

        Yes, that’s the acronym business. It makes US reporting hard to read, SCOTUS and POTUS and FLOTUS, simply because they have a 3 word country name, even with an indefinite article. I doubt most people know what is behind acronyms like CAT scan, which is about checking for cats. Very different to a CT scan or an NMR. GPS? It’s bad enough with the full name, but the shorthand makes it near impossible to know. Much originates in IT.

        50

        • #
          theRealUniverse

          The USians love their acronyms! Tech jargon as well makes it impossible to understand unless you are in the right area.

          50

          • #
            TdeF

            Medicine and business are not far behind. I have heard conversations in acronyms only. It’s a form of laziness, like most accents. Especially the Australian accent. No hard consonants and all the vowels become ‘a’. Like summa. acta. winta. gunna. warda. You drink warda.

            50

            • #
              Annie

              One of our memorable experiences was from when we first came to Melbourne; suburb will remain nameless! On an early visit to the local primary school for our two younger offspring ( following bullying episodes at their English one) I asked the principal how did they cope with bullies? He responded ‘we cancel them’…eh? What? A bit drastic, surely! Then the penny dropped; he meant ‘counsel’. A good case of being divided by a common language for one reason or another.

              71

            • #
              Len

              Sheel be right mate.

              30

            • #
              Asp

              I recently self-diagnosed my conditions as AAOS.

              00

        • #
          ivan

          CAT=Computer axial tomography

          20

    • #
      Annie

      What is even funnier, TdeF, is that Torpenhow is pronounce ‘Treppenah’ in Cumbria!

      51

      • #
        Annie

        BTW, did you know that there are quite a few (river) Avons in England?

        61

        • #
          TdeF

          No idea why anyone would give a red thumb to a fact? Thumb thing to do, I guess.

          60

          • #

            If it’s 2 in the morning and you’re peering at your phone in the darkness, so as not awaken your wife, and you read a comment that deserves an uptick. Now you know that the uptick and the downtick icons are very close together and should really have a larger separation so that sleepy old codgers lying awake at night reading erudite and interesting comments can give them an uptick without hitting the ‘thumbs down’ by mistake! Did it myself the other night and was mortified. Couldn’t reverse it and it’s bothered me for days. :(

            So all red thumbs are not necessarily true blue red thumbs!

            31

            • #
              Annie

              I’ve done it a few times FijiDave and didn’t have your excuse of being sleepy in tbe middle of the night most times…just clumsy fingers and thumbs.

              00

        • #
          tom0mason

          Yes Annie,

          There are at least 4 I’m aware of — One in Devon, one in Hampshire, one in Warwickshire, and lastly one runs through Bristol. There may be more. :-)

          30

        • #
          Asp

          Not as many as there are Alligator Creeks in Australia!

          10

  • #
    Javier

    OK, this is anything but new. It has been known since the mid-1980′s that the Sahara greening and drying follows the 23 kyr precession cycle because precession-linked insolation sets the position of the Inter-Tropical Convergence Zone, the climatic equator that determines how far North the West-African Monsoon reaches.
    Martine Rossignol-Strick worked out this relationship in 1985 in her article:
    Rossignol-Strick, M. (1985). Mediterranean Quaternary sapropels, an immediate response of the African monsoon to variation of insolation. Palaeogeography, palaeoclimatology, palaeoecology, 49(3-4), 237-263.
    https://eesc.ldeo.columbia.edu/courses/w4937/Readings/Rossignol_Strick.1985.pdf

    In this article from 2012:
    Green Sahara: African Humid Periods Paced by Earth’s Orbital Changes
    https://www.nature.com/scitable/knowledge/library/green-sahara-african-humid-periods-paced-by-82884405&nbsp
    We can read:
    “Longer stratigraphic sections extending as far back as the Miocene (Hilgen et al., 1995) contain hundreds of these sapropel layers, each representative of an earlier African humid phase and each paced by the characteristic orbital precession beat of 20,000 years (Figure 4). These sapropel layers are packaged into groups of 4–5 (Figure 4), reflecting the influence of slight changes in the shape of the Earth’s orbit around the sun (eccentricity) on modulating the strength of the precessional beat.”

    I hate this press releases that make it look like they have discovered something new, when in reality they just got more evidence for what is already known.

    130

    • #
      theRealUniverse

      Yep, true its certainly not the first mention of it.

      20

    • #
      Greg in NZ

      Can’t locate the paper I’d saved, yet here’s a (usually pro-Warmy) Nat Geo article, https://www.nzgeo.com/stories/deep-secrets/ , about ancient Lake Manuherikia in the South Island’s inland Central Otago basin (think frost/snow/ice/freezing winters and 30˚C summers):

      “Other clues as to what has happened are seen among the species that we have lost. Ancestral flamingos and swiftlets are strictly tropical today. And in the plant community the story is the same—eucalypts, casuarinas, cycads, palms and a multitude of laurals [sic] have all deserted New Zealand for warmer latitudes. From the time of the palaeo-Lake Manuherikia, the Earth cooled 8ºC during a period called the middle Miocene Transition, 14–13 million years ago. On top of this, the Pleistocene glaciations over the subsequent 10 million years brought another 5ºC drop in temperature—rather too much for New Zealand’s tropical heritage, which was all but eliminated.” Hmm, do they teach this in Enviro’n'mental Science 101 these days?

      Thank Huey and Tane, and their numerous wahine goddesses, for dropping the temp by 13˚C all those æons ago – all the crocs departed for your Great Southern West Island. Yet now we are supposed to dress in sackcloth and throw dirt in our hair because of a < 1˚C 'rise' since the chilly Little Ice Age? Critters "that survived the ever-descending temperatures, the retreat of the subtropical forests and the raising of the mountainous landscape we know today, became masters of adaptation". But… but… but who will think of the carbon tax!

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      Thanks Javier, I’ll add a note to the post. Useful. So this paper clears up some unlearning of the last 20 years.

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    • #
      sunsettommy

      I went over this very this last year at a large forum where I showed some published science that showed periodic changes that was around a 20,000 cycle from wet to dry back to wet. Only once did a wet phase fail to show up over a 100,000 year period.

      Warmists were so angry when I posted it since it damages their CO2 did it storyline.

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  • #
    David Maddison

    Even if the lie of anthropogenic global warming were true, natural warming has always been good for Civilisation.

    Can anyone name a period of history when natural warming was actually a bad thing?

    On the other hand, natural cooling has always been bad.

    This is why they don’t teach real history any more.

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    • #
      TdeF

      The very left in politics and universities do not want history taught, because it is a lesson in massive failures costing hundreds of millions of lives in the French, Russian, Cambodian and Chinese anti religion socialist and Marxist revolutions. Now we have a new phenomenon, Socialist Science. The total alignment of the left in politics with Man Made Global Warming is obvious. Explain that and you have the real science of the totalitarian movement which gave rise to the Soviet Union and the National Socialists under Hitler. The irony is that the Fascists now pose as Anti Fascist. That would be funny if they were not the same violent, masked murderous education free thugs with the same totalitarian ideals. Global Warming is unholy alliance of rampant capitlism and totalitarian politics, as with the Krupp backing of Adolph.

      First you have to create a threat which demand the suspension of civil liberties and free speech. Then get control and the money. Then take over. Even now Germany is trying to create a pan European army to defend against America and demanding France surrender its seat on the Security Council for the EU, which means Germany. Austria has just announced it has no interest in joining the European Army under Germany. We’ve been here before. It’s not about Global Warming.

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      • #
        TdeF

        I wonder how long it is before Germany demands the right or clandestinely assumes the right to nuclear weapons to match France, Britain and Russia. Are WW1 and WW2 ever over? Is the subjugation of France, Britain and Russia still on the wish list? All in the name of socialism and a fanciful United Europe, even against the wishes of most people. How did that work out the last two times? Was it only Britain and Russia who stayed independent and strong? History is doomed to repeat itself, especially if the lessons of history are not even taught.

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        • #
          TdeF

          A recent survey showed that 80% of millenials in the US think socialism is a preferable system of government! So much for democracy, suspension of free speech and the rule of law. Their safe spaces and freedom from ‘hate speech’ and the appointed fixed opinions are just preparing them for a life under authoritarian rule. Bernie Sanders say Climate Change should be treated like a foreign invasion. Sure, give Bernie the Presidency and he will quickly stop everything. Including freedom. Climate change will vanish overnight. They would no longer need it.

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      • #
        theRealUniverse

        ‘The irony is that the Fascists now pose as Anti Fascist. ‘ Disinformation is the key, confusion, good = bad, left = right, agents playing both sides. We are doomed. Nothing is straight forward anymore. I dont think its either socialist OR anything else, control is control on both platforms.

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    • #
      PeterS

      David M it’s simpler than that. Even if the lie of anthropogenic global warming were true, much of the world is not taking it seriously given the massive number of new coal fired power stations being built. Only a small number of nations are being stupid about all this and we are one of them.

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      • #
        David Maddison

        PeterS, I think Australia has fallen for the AGW lie much more so than any other country, even Germany.

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        • #
          PeterS

          I think New Zealand is worse but yes we are at/near the top of the list of the most stupid nations for falling for the CAGW scam and hoax.

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          • #
            TdeF

            NZ are in trouble with cow and sheep farts though. That is most of their contribution to Global Warming as they are a hydro country. The cows and sheep just have to go. Wine too because of the output of yeast in fermentation. No more cheese, wine or sheep. No parties then.

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            • #
              PeterS

              What about humans? Surely they must go too. Oh wait! That’s on the Greens agenda already – except for themselves of course.

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            • #
              Sambar

              And the gum boots Tdef, where will all the surplus gum boots go?

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            • #

              The drongoes who have been, and are, running this country (NZ) are up to their hocks in the the Global Warming scam. They’re determined to wreck our economy because of their irrational fears of Armageddon and see our bovine and ovine residents as sinister as Orcs hiding in the scrub just waiting to precipitate a major catastrophic climate swing. And if it suits their political agenda even better.

              As for’cow farts’; the methane produced is carbon neutral. An interesting opinion piece here by Dr Doug Edmeades shows how.

              Methane is short-lived in the atmosphere. It hangs around for about 10
              years before it is converted to CO2. For every unit of carbon the animal
              emits as CH4 it must ingest the same amount of carbon from its plantbased feed source, which, remember, comes initially from the CO2 in the
              atmosphere.
              From the animals perspective every bit of carbon it emits as methane it
              mopped up as carbon in its feed. The animal is both the source of the
              carbon in methane and it is also the sink for the equivalent amount of
              carbon in CO2. In this sense the carbon-methane cycle: methane-to-CO2-
              to-forage-plants-to-animals-to-methane, is a closed cycle.

              20

              • #
                AndyG55

                “The animal is both the source of the carbon in methane and it is also the sink for the equivalent amount of carbon in CO2.”

                Actually, a cow only puts out a fraction of the “carbon” it consumes as “carbon” in methane.

                The rest is converted to meat.. for consumption.

                Include us, yep, the manufacture and consumption of meat is a closed system, and no less, but probably far more “carbon neutral” that burning wood pellets.

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        • #
          OriginalSteve

          I think Australians a just pig ignorant on most hard and political science.

          Mind you, it doesn’t help when you have universities and MSM run by Marxist Commissars…

          30

      • #
        TdeF

        Don’t you love the pomposity of anthropogenic instead of man made? It sounds so.. scientific with a bit of ancient Greek. So instead of calling it an outright lie and offending the sensibilities of the supremely sensitive, we should call it an ‘untruth’ or ‘intentionally deceitful misdirection’.

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  • #
    toorightmate

    My first job was as a lumberjack in the Sahara forest.
    We sure had to work hard, but we got the job done.

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  • #
    PeterS

    It appears the yellow vest movement is spreading. Canada is next: https://globalnews.ca/news/4770509/yellow-vest-protests-canada/
    I suspect we will have ours eventually especially if Shorten becomes PM. No doubt it will be interesting times this year.

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    • #
      AndyG55

      Shorten is controlled by the Union Leaders.

      Will the union rank and file start to get “annoyed” by excessive taxes, electricity costs, loss of manufacturing jobs etc etc. ???

      hmmm.. time will tell.

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  • #
    el gordo

    The Simpson Desert is still on the move, we need to do some terraforming.

    ‘The dunefields of the Simpson Desert are still advancing, its brilliant red dunes are moving onto the Strzelecki floodplain, smothering entire eucalypt forests in the process. In places, the only indication that a forest was there are the occasional eucalypt crown protruding from the sand.

    ‘The 130,000 km2 of the Simpson Desert comprise half the dune-desert area of Australia. At present, 40 % of the continent is covered by dunes.’

    Australia: The land where time began

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  • #
    RoHa

    Sun? Nonsense. It’s CO2 that has made the Sahara into a desert.

    30

  • #
    OriginalSteve

    Speaking of silliness……

    “What no – wifi out in the desert? I quit!!”

    https://www.abc.net.au/news/2019-01-04/the-british-army-was-millennial-snowflakes-and-selfie-addicts/10685194

    The skills of the current generation fit the needs of the “changing battlespace”, the army says

    Recruiters shrug off campaign criticism, pointing to an increase in diversity
    Or at least, the British Army does.

    “Me me me millennials”, “phone zombies” and “selfie addicts” are the target of a new recruitment campaign being rolled out by the UK Ministry of Defence in a bid to bolster recruitment numbers.

    The posters laud millennial “binge gamers” and “class clowns” for their “spirit” and “drive”.

    “Your Army needs YOU,” the posters read — a throwback to the Lord Kitchener recruitment posters that came to be one of the defining images of World War I.

    Colonel Ben Wilde, assistant head of Army recruitment, told the defence-run Soldier Magazine the skills of the current generation “would fit the need for operating in a changing battlespace”.

    n one ad, a father laments that his son has stayed up all night playing video games.

    “Stamina, don’t underestimate it,” a voiceover remarks, praising the gamer’s “dedication”.

    In another, a supermarket trolley worker who is mocked by her colleagues for being a “slow millennial”, is commended by the Army for her perfectionism.

    However, the campaign has not been without scrutiny.

    On social media, some questioned whether taking aim at millennials was likely to entice them to join their ranks.”

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  • #
    pattoh

    OMG!

    The Amazon will be short on fertilizer!

    How will George’s Sugar Cane to Ethanol Bio-fuel Schemes ever get any Green Finance?

    40

  • #
    JoKaH

    The Amazon will be short on fertilizer!

    And I thought the Shorten BS was a sort of fertilizer!

    30

  • #
    Phoenix 44

    Fits in with the evidence for multiple Human migrations out of Africa that then die out as climate changes and the path north becomes impossible.

    30

    • #
      el gordo

      There have been quite a few migrations out of Africa apart from homo sapiens, neanderthal and homo erectus, there was also the Flores hobbit (homo floresiensis). This character walked to Indonesia one million years ago.

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  • #
    Kinky Keith

    Without going into the detail, it’s really great to see the link between how the Earth presents itself to the Sun and the resulting geo_sedimentary evidence of periodic desertification and regrowth.

    Axial tilt, precession, distance from the Sun: periodicity, being matched the geological indicators for desert/low moisture.

    It’s making the claim of a perfect, natural, stable climate prior to man’s need for energy on tap more than a bit legless.

    KK

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  • #
    Global Cooling

    Qattara Depression in Egypt is a large area below the sea level. There has been may plans to fill it for various reasons.
    https://www.sciencedirect.com/science/article/pii/S1876610213011090
    A 40 mile (60 km) canal or tube would be needed.

    I did not find reports about cyclic filling of this or other African areas. More use of search engine may help, but just asking.

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    • #
      Steven Fraser

      Death Valley in the US would also be a candidate, but I would do it for other reasons: To make an inland saltwater recreational area.

      30

    • #
      theRealUniverse

      When the Mediterranean sea was empty 10,000,000 years ago, estimates the temperature at the lowest point was 80C! due entirely to the increase of pressure as the depth below that sea level was around 5000m!

      00

  • #
    Steven Fraser

    For those that care about such things, US President Trump’s nominee for National Science Advisor was confirmed.

    He’s a Meteorologist, Professor, Administrator, Researcher and Forecaster.

    His CV is at

    http://kkd.ou.edu/Droegemeier_Full_CV_2018.pdf

    He took some flak for one of his comments during the Hearings. When asked a question on Climate by Senator Cruz (you can look up the specific question online) he responded to the question, in part, with “I don’t study Climate”. Critics called this a ‘dodge’. I think it was a great response.

    And, his first name is Kelvin.

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  • #
    Cameron

    Does the study predict when the next greening is likely?
    Is it already happening? Satellite data show greening on the southern edge of the Sahara, is that more to do with this cycle than an increase in atmospheric CO2? I presume the southern Sahara would be the first to green and the last to brown(?).

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