From the “is there anything climate change can’t do when models are involved?” department. On the plus side, this study illustrates how natural climate cycles were involved. – Anthony
Unravelling the climate behind the collapse of Bronze Age civilizations
Stockholm University
The most severe droughts in the ancient Eastern Mediterranean arose when multiple natural climate cycles coincided, according to a new study from Stockholm University published in Science Advances. The findings shed new light on the climate conditions surrounding the Late Bronze Age collapse and may help improve understanding of future drought risks in a warming world.
“Rather than being caused by a single climatic event, we found that the most extreme droughts emerged when natural climate cycles operating over different timescales coincided. This helps explain why the drought associated with the Late Bronze Age collapse were so severe”, says Katherine Power, PhD student, Department of Physical Geography, Stockholm University, and first author of the study.
Around 3,200 years ago, many of the great civilizations of the Eastern Mediterranean, including the Mycenaeans, Minoans and Hittite Empire, experienced widespread societal collapse. Although severe droughts have long been linked to this period, the climatic processes behind these events remain uncertain. To investigate this, Katherine Power and Qiong Zhang, professor in paleoclimate modelling, Department of Physical Geography, Stockholm University and co-author of the study, used a state-of-the-art climate model to reconstruct the evolution of the Mediterranean climate over the past 8,000 years.
“Our results show that the region underwent a gradual drying trend over thousands of years, driven by slow changes in Earth’s orbit. Superimposed on this long-term trend we also found shorter-term fluctuations in the Atlantic Ocean and atmosphere”, says Katherine Power.
The researchers found that most severe droughts occurred when several natural climate cycles aligned, temporarily reinforcing one another and producing droughts far more intense than the long-term drying trend alone.
“The convergence of these processes pushed the Eastern Mediterranean beyond a critical hydroclimatic threshold, reducing water availability and increasing pressure on agriculture and food security within already vulnerable societies”, Katherine Power says.
These findings change how we think about past droughts, the researcher say, and understanding these processes is highly relevant today:
“The Mediterranean is one of the world’s climate change hotspots and the area is projected to become warmer and drier during the coming century. Our findings suggest that future drought risk may depend not only on long-term human-driven warming, but also on how natural variability in the Atlantic Ocean interacts with that background trend”, Katherine Power explains.
By revealing how different climate processes combine to amplify drought, this research can provide new insights into the risks of future hydroclimatic extremes in a warming world, the researchers say.
The study “Holocene ocean-atmosphere coupling and Mediterranean sensitivity to Atlantic circulation: Lessons from the Late Bronze Age collapse” was published in Science Advances. DOI: 10.1126/sciadv.aed5439.
For this research the model EC-Earth was used.
Journal
Science Advances DOI 10.1126/sciadv.aed5439
I wonder whether the 7 years of feast and 7 years of famine were actually cycles of El Nino and La Nina. if so Joseph must be the first climate scientist on record.
It wasn’t Climate Change which caused their collapse, it was, more likely, A lack of societal Climate Resilience. They were simply unprepared for the ever changing climate.
No water storage
No drainage
Structures susceptible to the whims of weather
Has there continued to be evidence of a 7 year cycle in historical records outside of that one report? We otherwise can simply call that an isolated event as the source of the warning given to Joseph has not left a record of whence came the data.
Don’t be silly, Tony, a real climate scientist doesn’t bother with mundane things like measurement. How could Joseph be a climate scientist with nothing but empirical data to work with?
They ran a model. The author then exhibited a distinct lack of humility. Her discussion quotes given here lack words like may, might, or could. Of course, she worked under the tutelage of a professor and a doctoral committee, who should have reined in her confidence in the model findings. That said, various scholars and models suggest that climatic conditions of the era were likely a contributing factor among many.
Interestingly, the characterization of climate of that era as seen in Paleoclimate data (pollen, speleothems, tree rings, lake cores, sea-surface temperatures) point to a multi-decade to multi-century period of cooler, drier conditions and reduced rainfall. As in the little ice age, again we have the suggestion that cold was bad and was accompanied by dry conditions. The authors then tried to correlate stressful, cold, dry conditions of the past with current warm and wet conditions, just the opposite of the late bronze age collapse.
Gotta say something about projected climate change in the modern era in order to get their funding and get published.
I wonder if any of the reviewers even asked if the time span of the cycles had a plus or minus in their range. For example, the Atlantic Ocean currents changed on the 3rd August 1875BC. Which caused the droughts of 185, ’74 and ’73.
Or just maybe the current changed 20 years earlier and was cancelled out by the jet stream changes which did occur in 1875BC.
If you do not know the range of uncertainties in the data, including the cycle length, the phase and it’s interaction to all other events, then the report just become complete trash.
In the modern era when the phase and signal of multiple triggering events can be directly measured, the respective weather bureaus cannot provide you with an accurate weather forecast more than a few days out. Anything about a drought in as short as 5 years time is simply a guess.
Knowing the limitations of the current analysis, I call BS on anyone trying to guess the cause of a drought in the bronze age. And I shouldn’t be alone in this assessment. Was there even a drought? And did it end the bronze age civilisations?
So, a climate model was used to model something about which they have no real details, only proxies. What could go wrong?
Yep.
Haven’t they heard about splicing other selected sources onto the proxies to create the impressions your paper needs in order to get published & funded?
This study shows the typical fraud of science that is dependent on unproven models.
“Our results show….”
No. Your results “show” nothing. You have found nothing. They are not facts. Your model is a complex hypothesis. Your “results” are not measurements of the real world; your results are simply calculations, quantifications of your hypothesis. An hypothesis cannot prove itself.
Your best phrasing might be: “calculations based on our model suggest…..”
So test your model and its quantifications against real world measurements. Until you do, your study is somewhere among speculation, fantasy, and unproven theory.
Modern science where money and politics are involved is in trouble.
But, but, but – we did not use any old model but a ‘state-of-the-art’ climate model.
(Don’t look behind the curtain for how well the ‘art’ performs)
Ha ha yeah, and I bet it was robust too. I mean really, really robust.
…. and MyUserNameRetarded or one of the other gullibles (Banton) will be along soon to tell us it was fact-checked.
What does Sweden know?
It just appeared from under a mile of ice.
Lessons from conjecture? For what else is a climate model?
But the only thing to care about is GHGs?
Yeah. Once we control all human CO2 emissions, climate will all be peachy for ever more. Of course, termites, plankton and Carrington events might decide to throw a monkey wrench into the plans of men. But don’t worry be happy. We’re doing it for the children.
For the children of the well of folks.
All others will be cyphers trying to eke out a living.
There is a term not used often enough. Adapt. We now have desalination plants that can make all of the water we need with abundant energy. We can and do build green houses to control the weather somewhat. These choices were not available in the past civilizations. Of course if we continue with net zero madness we probably wouldn’t be able to in the future either.
The period known as the Climate Optimum, during which time it was warmer and wetter than now ended about 5,000 years ago. Then, things started to cool again, so these severe droughts some 3,200 years ago happened when it was cooler, not warmer. If indeed the current warming continues, and there are no guarantees on that, then we will be experiencing wetter, not drier conditions. Oops.
‘Around 3,200 years ago, many of the great civilizations of the Eastern Mediterranean, including the Mycenaeans, Minoans and Hittite Empire, experienced widespread societal collapse.’
I thought all this badness was on account of the Sea Peoples…
/s
Why bother with “a state-of-the-art climate model” when Hausfather assures us that “We found that climate models – even those published back in the 1970s – did remarkably well, with 14 out of the 17 projections statistically indistinguishable from what actually occurred.”
Throw some ideas on the wall and tell a story. Move along.
I went and researched eastern Mediterranean Bronze Age civilization collapse about 3200 years ago. It wasn’t only drought as simplistically asserted by this paper’s models. There was a cluster of strong earthquakes over about 50 years that severely disrupted those civilization’s cities (shown by archeology) . There was the invasion of ‘Seapeople’ into their port cities—perhaps drought induced migration from elsewhere, as shown by contemporary ‘writings’. That in turn disrupted the long sea trade routes these civilizations depended on to import the copper and tin they needed to make bronze. For example, much of the tin came from mines in SW Britain. Copper was mainly sourced from mines in Cyprus.
As you say, Rud:
Nur, Amos “Earthquakes, Armageddon, and the Dead Sea scrolls” AAPG Bulletin, vol.82, no.11, pp.2154-2155, Nov 1998
Abstract: Why are there so many ruins especially in the Mediterranean and Near East? Most people think that time and war are responsible. But actually most of the damage we now know was caused by historical earthquakes. Simple examples are ancient Troy, Micenea, Crete, and biblical Jericho, where earthquakes can explain the as yet unexplained catastrophic end of these sites at the end of the bronze age.
My favorite book of this type growing up was “Lost Cities and Vanished Civilizations” (1962) by Robert Silverberg.
https://en.wikipedia.org/wiki/Lost_Cities_and_Vanished_Civilizations
Rud, have you seen any of the YouTube videos on copper mining around Lake Superior and the possibility of that copper ending up in bronze age Europe. I’m more than skeptical, but the possibility of a trans-Atlantic copper mining operation is entertaining for sure. I haven’t connected the purported years involved but you’re on top of that. I’d be interested in your opinion of this “field” of study. Here’s one vid:
aibot generated crap. I have been removing all of these that pop up in my feed.
I have visited those UP mines, and have both blister copper and copper/ silver nuggets from them. They were exploited by native Americans before being mined in the Late 19th and early 20th centuries. That there could have been transatlantic exploitation back then is pure fantasy.
That’s kinda what I thought. Thanks for responding.
Wow, some close-minded responses here. Instead of dismissing out of hand a hypothesis that does not align with your worldview, try answering some of the questions raised. Otherwise, you’re behaving very much like the climate fanatics.
Thank you Rud, the authors should have researched the alternatives to their hypothesis before they published. I found this very interesting account of the collapse from, of all places, the BBC: https://www.bbc.co.uk/history/ancient/greeks/minoan_01.shtml. There, they list as possible causes: volcanic eruption, a tsunami, and large-scale, substantial cooling caused by large amounts of SO2 in the atmosphere. And they do not mention drought at all.
The cooling effect of SO2 is particularly interesting, since it would suggest that our efforts to reduce SO2 emissions over the last half a century and more could have had a substantial warming effect. But I haven’t heard of any recent papers looking at this effect, and comparing it with the effects of CO2.
Gotta wonder if the Minoan eruption of Thera was part of the model. It was probably pretty significant to the Mycenaean people. Could wiping out one of the largest Mediterranean trading and military centers have an effect on the region’s economy?
Looked that up, since wasn’t mentioned in my AI results. Happened about 400 years earlier, so although locally disastrous was apparently a not a proximate cause of the later ‘simultaneous’ decline of several further east Bronze Age civilizations.
Certainly have to consider it a precursor, especially being a large trade center.
My only complaint with the paper is the present-day influence of climate jargon used in the AGW narative, such as “caused by a single climatic event“. What, dear writer, is a climatic event? Or “climatic processes“?
Two readings of interest are:
1: https://archive.aramcoworld.com/issue/201403/last.lakes.of.the.green.sahara.htm
and,
2: https://en.wikipedia.org/wiki/African_humid_period
Don’t know if I’d open that African Humid Door no telling what kind of stogies might come rolling out
I salute the Master! I am not worthy!
I know! A “climate event” is weather caused by climate….
Ah, wait. Now that I think about it, climate is determined by weather, not the other way around.
Never mind.
It is possible that variables in weather, etc., caused a climate shift (long term average) that contributed, but certainly not the “climate change” of today with its radical CO2 cause.
I’ve always thought climate change was behind the late bronze age collapse, just as climate changes led to the rise and fall of the Roman republic and empire, the medieval warming period, the little ice age, and the current warming. Nothing else could change so much so smoothly and globally.
But to model it? What for? What data can it possibly use? What data can it possibly be verified against?
What a waste.
Another modeling orgasm comes along; science then slows to a crawl until the baloney recedes into the past then a recovery begins…..
[The authors] “used a state-of-the-art climate model to reconstruct the evolution of the Mediterranean climate over the past 8,000 years.”
Fat farking chance.
I’ll believe it when Michael Mann complains it created the Medieval Warming and Little Ice Age.
But it’s good news if their results can be sliced into say 20 year increments. Then we could check their results against reasonably well known data.
And check whether their state-of-the-art climate model is worth a brass razoo.
Are any commentators here actually familiar with the programme that is called a model in this paper? Can you give me an idea of what the parameters were and what initialising data was used to prime the process.
The devil is in the detail.
As I age, several ordinary words have become more and more sickening and “model” is one of them. However, I think one word has not just been distorted but rendered into an obscenity – I refer to “anomaly”. The trick behind defining anomaly as an authentic representation of anything real is actually acting as a father to a lie.
Model is a tool. It is a symbolic representation of reality (or a piece of reality).
Models transform inputs to outputs and are useful in studying phenomena or estimating performance (such as electronic circuits).
The flaws in models are not software errors. Those are easily identified and corrected. It also is not equations, which can be tested and verified.
The flaws in models are assumptions, identified, hidden (aka bias), or not recognized (human error). The challenge to models is always challenging the assumptions and the assumptions include the inputs.
Anomalies. I have a major beef in the way they are used today, along with a long list of Trans-Reality Alarmist terminology.
An anomaly is an abnormality, an irregularity, an outlier, or an oddity. In a normal distribution curve, an anomaly is generally outside the 3rd sigma (or 4th or 5th).
Anomalies are not the difference between a datum and the average of a data set. Anomalies are chosen because of the non-use of variation. Climate alarmists just can acknowledge natural variabilities.
The way it is used is akin to the “tave” and “GST” calculations.
So yes, The trick behind defining anomaly as an authentic representation of anything real is actually acting as a father to a lie.
The authors clearly do believe the ‘human driven long term climate warming’. And their evidence for that is …. ?
“Scientists say….” is the answer to your question.
Is climate change a troupe of monkeys ??
It sure has a lot of tall tails .
😉
What? The Bronze Age didn’t die due to CO2?
Models have become a bad word. Almost like a coven of witches sitting around a simmering pot of unknown substances. We’re down to using the same approach (models) for a complex system (climate) as we did to identify the college football teams to play in a national championship game.
The Mediterranean is the fastest warming body of deep water on the globe. It is close to hitting monsoon conditions already this year and the monsoon season of the Med is trending toward earlier start. That will increase rainfall around the Med.
The bronze age collapse is considered to be more than just climate change. It seems to combine climactic factors, social factors and economic factors just as we are likely to see (well our descendants) an ‘oil age collapse’.
Nevertheless historical climate change related civilisational collapse is a lot more real than today’s scares.
My take on this is that astonishingly enough, climate manages to change, all on it’s own, even without any changes in CO2 levels.
Something that modern models seem to have had programmed out of them.