Climate and Drought Lessons from Ancient Egypt

From the USGS:

A map of the Nile Delta in Ancient Egypt times...

Using Fossil Pollen to Augment Historical Records

Ancient pollen and charcoal preserved in deeply buried sediments in Egypt’s Nile Delta document the region’s ancient droughts and fires, including a huge drought 4,200 years ago associated with the demise of Egypt’s Old Kingdom, the era known as the pyramid-building time.

“Humans have a long history of having to deal with climate change,” said Christopher Bernhardt, a researcher with the U.S. Geological Survey. “Along with other research, this study geologically reveals that the evolution of societies is sometimes tied to climate variability at all scales – whether decadal or millennial.”

Bernhardt conducted this research as part of his Ph.D. at the University of Pennsylvania, along with Benjamin Horton, an associate professor in Penn’s Department of Earth and Environmental Science.  Jean-Daniel Stanley at the Smithsonian Institution also participated in the study, published in July’s edition of Geology.

“Even the mighty builders of the ancient pyramids more than 4,000 years ago fell victim when they were unable to respond to a changing climate,” said USGS Director Marcia McNutt. “This study illustrates that water availability was the climate-change Achilles Heel then for Egypt, as it may well be now, for a planet topping seven billion thirsty people.”

The researchers used pollen and charcoal preserved in a Nile Delta sediment core dating from 7,000 years ago to the present to help resolve the physical mechanisms underlying critical events in ancient Egyptian history.

They wanted to see if changes in pollen assemblages would reflect ancient Egyptian and Middle East droughts recorded in archaeological and historical records.  The researchers also examined the presence and amount of charcoal because fire frequency often increases during times of drought, and fires are recorded as charcoal in the geological record. The scientists suspected that the proportion of wetland pollen would decline during times of drought and the amount of charcoal would increase.

And their suspicions were right.

Large decreases in the proportion of wetland pollen and increases in microscopic charcoal occurred in the core during four different times between 3,000 and 6,000 years ago. One of those events was the abrupt and global mega-drought of around 4,200 years ago, a drought that had serious societal repercussions, including famines, and which probably played a role in the end of Egypt’s Old Kingdom and affected other Mediterranean cultures as well.

“Our pollen record appears very sensitive to the decrease in precipitation that occurred in the mega-drought of 4,200 years ago,” Bernhardt said. “The vegetation response lasted much longer compared with other geologic proxy records of this drought, possibly indicating a sustained effect on delta and Nile basin vegetation.”

Similarly, pollen and charcoal evidence recorded two other large droughts: one that occurred some 5,000 to 5,500 years ago and another that occurred around 3,000 years ago.

These events are also recorded in human history – the first one started some 5,000 years ago when the unification of Upper and Lower Egypt occurred and the Uruk Kingdom in modern Iraq collapsed. The second event, some 3,000 years ago, took place in the eastern Mediterranean and is associated with the fall of the Ugarit Kingdom and famines in the Babylonian and Syrian Kingdoms.

“The study geologically demonstrates that when deciphering past climates, pollen and other micro-organisms, such as charcoal, can augment or verify written or archaeological records – or they can serve as the record itself if other information doesn’t exist or is not continuous,” said Horton.

This study, Nile delta response to Holocene climate variability, was published in the July edition of Geology, and was authored by Christopher Bernhardt, USGS; Benjamin Horton, Penn; and Jean-Daniel Stanley, Smithsonian Institution. Support for the work came from the University of Pennsylvania, the U.S. Geological Survey, and the Smithsonian Institution.

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Patrick Davis
August 17, 2012 4:16 am

It is understood that rainfall patterens changed over what is now Ethiopia, changing water inflows to the Blue and then White Nile rivers, drying out Geza around about this sort of time. Must have been all those SUVs.
[;) ~ac]

North of 43 and south of 44
August 17, 2012 4:19 am

I wonder how high those CO2 levels were before the big drys hit?

August 17, 2012 4:23 am

“Ancient pollen and charcoal preserved in deeply buried sediments in Egypt’s Nile Delta document the region’s ancient droughts and fires, including a huge drought 4,200 years ago associated with the demise of Egypt’s Old Kingdom, the era known as the pyramid-building time.”
I find it hard to believe they built these mega pyramids around that time. These people may have simply inherited these buildings. Like Mann, Hansen, etc have their own narrative of how global warming occurs, the mainstream academic also have their own narrative of how/when the pyramids were built.
Dr. Robert Schoch, a geologist who thinks Pyramids may have been a lot older. based on geological evidences (weathering).
Also, when you take a closer look at the design of the mega pyramids, etc, the mainstream narrative of pyramids building makes even less sense. Ask granite sculpture artists what they’d need to produce large Ramses granite statues, granite objects with perfect 90* inside corners, etc found inside mega pyramids and outside.
I’m going with the narrative what these people 4,000 years ago may have simply inherited these places. Great Sphinx, mega pyramids, granite statutes, etc are probably closer to 10,000 years old. Maybe 12,000-15,000 years old. It’s not the only place that is old. There are some places all over the world that are that old. Remember, the end of ice age 12,000-13,000 years ago that probably caused a big change in weather patterns when the sea level rose 400 feet.

Luther Wu
August 17, 2012 4:26 am

If we could determine what triggered the droughts…
Hope we aren’t “due” for another, although folks might think we’re already in one, in this neck of the woods.

August 17, 2012 4:27 am

It’s worth noting that the Sahara Desert was once a lush savannah with plentiful rainfall about 10,500 years ago. This, of course, had nothing to do with CO2. It was because the axial tilt of the earth at that time created air pressure and temperature imbalances (the sea absorbs more heat from the sun, making it cooler than land), which brought monsoon rains to the Sahara. Rock paintings found in the Sahara at that time even show people swimming! In a nutshell: our planet’s climate and weather is cyclical due to its orbit around the sun and axial tilt.

August 17, 2012 4:34 am

The Egypt area is particularly susceptible to expansion, contraction and latitudinal shifting of the Sahara in response to the changing sizes, positions and intensities of the permanent climate zones.
Such changes appear to be a global air circulation response to changes in the vertical temperature profile of the atmosphere caused by a top down solar effect primarily due to spectral changes affecting ozone quantities at different levels.

August 17, 2012 4:47 am

Pyramids… They didn’t build that. Their government did.

Caz in BOS
August 17, 2012 5:03 am

@Nerd – you have some of your timelines crossed. Pyramid building happened from ~2700BCE to ~2200BCE. It ceased when the mega-drought hit. The Indus Valley (Harrapan?) civillization collapsed then, too. The weathering that indicates the older age you refer to is on the Sphinx, not the pyramids. The sphinx is carved out of a natural rock, and may have been the site of rituals going back thousands of years before the Egyptians carved a face on it.

richard verney
August 17, 2012 5:13 am

There was a very interesting programme on English TV (BBC 4) a few months ago about this very subject. It was about 1 hour long and about half was devoted to natural climate change with no AGW mantra. I seem to recall that some Expert in Greenland ice/Arctic ice/Gulf stream patterns was talking about a natural 1500 year cycle.
I cannot recall what the programme was called and doubt that it is still on BBC iplayer. At the time, I posted a comment about the programme on the Bishophill cite. If the programme can be tracked down, it is well worth a view.
Humans would not be inhabiting Earth but for past climate change. Humans have always been able to adapt and if climate change is truly happening, Humans will easily adapt.

Jay Curtis
August 17, 2012 5:35 am

Climate zones changed dramatically just 1000 years ago when the Anazazi peoples of Chaco canyon in New Mexico and Mesa Verde in Colorado migrated from those areas to the Rio Grande basin. At approximately the same time, the Vikings left Greenland. At Chaco, not only was there sufficient water to store in reservoirs and to use for irrigation, but there was also forest. The ancient roots of those trees can be found just beneath the sand. Chaco went from semi-arid to a bleak desert in a very short time.

August 17, 2012 5:38 am

@ richard verney
I think you’re referring to BBC’s Orbit: Earth’s Extraordinary Journey? I also enjoyed this three-part documentary about natural climate cycles, especially because there was no AGW crap involved. It can still be viewed online at the following links, highly recommend everyone to give it a go, well worth the time:
Episode 1:
Episode 2:
Episode 3:
Note: The two female presenters are pretty hot too! 😀 Hot girls + interesting science = must watch.

Jean Meeus
August 17, 2012 5:46 am

Don wrote:
“It’s worth noting that the Sahara Desert was once a lush savannah with plentiful rainfall about 10,500 years ago. This, of course, had nothing to do with CO2. It was because the axial tilt of the earth at that time created air pressure and temperature imbalances….”
The obliquity of the Earth’s axis reached a maximum of 24 deg 14′ about the year 7530 BC.
Presently, the tilt is 23 deg 26′. Can a difference of only 48′ result in a sensible effect on the climate of a region? Just asking.

Alan Watt, Climate Denialist Level 7
August 17, 2012 5:47 am

The way the Egyptians dealt with floods, droughts, etc., was to sacrifice virgins until the Gods relented and made things right again.
Some things never change.

cui bono
August 17, 2012 5:53 am

richard verney says (August 17, 2012 at 5:13 am)

That was a brilliant documentary – I cited it here at the time for the amazing work done discovering the 1500 year cycle by checking how far Icelandic ash trapped within icebergs got before the ice melted and the ash settled to the bottom of the Atlantic. It’s at about 30 minutes in:

Kudos to the BBC, for once.

cui bono
August 17, 2012 5:58 am

Yaggh! Wrong link for some reason. Here’s the real one:

August 17, 2012 6:04 am

I recently had the pleasure of visiting Turkey and the Greek island of Simi. In many places you can see evidence of ancient agriculture in places which are today not viable. On Simi for example, I photographed many examples of very old stone terraces high up on the mountains, while today the island is dry as toast, supporting only goats and olive trees. Roman warm period? Medieval warm period? Who knows, but clearly the past was much wetter than it is today.
The same thing can be seen in the Uubamba Valley in Peru, where the Inca civilization developed between about 1000AD and 1300. They built fantastic terracing and irrigation systems right up to the mountain tops, which presumably supported a rapidly growing population and empire. The Spanish arrived more or less at the end of the warm period and optimistically built their capitol
at Cusco, which promptly dried out and is today a high almost-dessert.
Trouble is, even though evidence of natural variability is obvious to anyone with eyes, today every climate change, hotter, colder, wetter, drier, is taken as de facto evidence do AGW. No matter what happens in the future, it will have been “our fault.”

August 17, 2012 6:11 am

Article on BBC site entitled “The Fall of the Egyptian Old Kingdom” by Professor Fekri Hassan:
See section 4: Climactic change.

August 17, 2012 7:13 am

Timbuctoo was once a large and presumably thriving city. Has anyone else seen the amazing aerial footage which reveals its original extent? Today it is a fraction of its original size.
I have been sneered at and derided for mentioning this as an example of pre industrial ‘climate change’!

August 17, 2012 7:20 am

Actually, there was more than one reason for the demise of the First Kingdom. Pepi was the last pharaoh of the dynasty, and lived to be over 100. To this day, he is the longest reigning king ever know anywhere/anytime. He became pharaoh at age 6. Out lived all his heirs. An obvious power vacuum. Also, if you go back in the C13 record, you will note that the First Intermediate Period started with a bump in the C13 content. Gee, might the sun have something to do with climate and cosmic rays? Who wudda thunk it? I always thought it was evil coal companies.

Mike M
August 17, 2012 7:25 am

The timing appears to have the possibility of tying in with the eruption of Thera (Santorini) which may have cooled the planet causing widespread drought for a very long time.

The fall of Minoan civilization is usually dated to around 1450 B.C. Geologists judge the eruption as far more violent than the 1883 eruption of the volcanic island of Krakatoa…
This study puts even more impetuous on finding out more precisely just how far ‘more violent’ it was.

Paul Linsay
August 17, 2012 7:33 am

It’s about the same time as Joseph of the Bible. Interesting.

August 17, 2012 8:06 am

If you have grassland and you want to turn it into desert just introduce goat herders. Goat herders will always overgraze the land, and afterward you get desert.
The present day Egyptians are destroying their best agricultural land at the moment by a mixture of building, growing cotton on marginal land and increasing erosion down stream of the Aswan dam.

August 17, 2012 8:14 am

@ Alan Watt. The Egyptians did not practice human sacrifice. To suggest that they did is to slander a great ancient civilisation.
Similarly, while there is some contentin over the age of the Sphinx, there is no doubt at all that the major pyramids were built during the Fourth Dynasty. We know this because they contain grafitti and other marks that could only have been placed there during construction and these marks relate the date the stones were laid.
It is highly unlikely that there is a connection with the fall of the Minoan civilisation as the Egyptian Fourth Dynasty ended circa 2200 BC and this is some 800 years before the fall of the Minoans. One could argue that the Old Kingdon fell before the Minoans even rose.
That climate change was a factor in the fall of the Old Kingdom is no real surprise. The society was reliant on the flooding of the Nile and a failure of the flood meant very lean times indeed. Such a failure would also be seen as a sign that Pharoah was no longer in favour with the Gods and lead to the collapse of the government itself.

David Ross
August 17, 2012 8:19 am

Ancient Egypt: husbanding a crucial resource requires huge collective action and central planning, which fosters a centralized government, which in turn becomes totalitarian -a “hydraulic empire”. After the sweat and blood of the long-suffering peasants is expended on sensible projects -canals- an absolute monarchy and an elite priesthood sets them to work on senseless ones -pyramids- to avert non-existant catastrophes. Subsequent generations then take the propaganda of their forefathers as religious truth and the process continues for thousands of years.
But nothing lasts forever.

Look on my works, ye Mighty, and despair!
Ozymandias, Percy Shelley

The ancients would make burnt offerings to their gods but the new religion require us to “sequester” our carbon to appease Gaia. Parodying such idiocy has a long history.
Aristophanes presented his latest play The Birds at Dionysia in 414 BC. It describes how the birds of the earth conspire to establish a kingdom in the sky and extract tribute from the humans for allowing their (carbon) offering to pass through their territory to the gods.

PISTHETAERUS The air is ‘twixt earth and heaven. When we want to go to Delphi, we ask the Boeotians for leave of passage; in the same way, when men sacrifice to the gods, unless the latter pay you tribute, you exercise the right of every nation towards strangers and don’t allow the smoke of the sacrifices to pass through your city and territory.
CHORUS We forbid the gods, the sons of Zeus, to pass through our city and the mortals to send them the smoke of their sacrifices by this road.

Of course, it all goes wrong.

PROMETHEUS Since you founded this city in the air. There is not a man who now sacrifices to the gods; the smoke of the victims no longer reaches us. …

The Birds is not read in our schools anymore, but it did give us the phrase “cloud cuckoo land” : )

Jim Clarke
August 17, 2012 8:33 am

Never has humanity been more capable of adapting to climate change than we are today. Yet our ability to control the climate is no greater than it was 4,000 years ago. So why is all the fuss and expense devoted to trying to control the climate instead of adapting to it?
Eventually, all attempts to control climate change will prove fruitless and we will adapt…just not a well as we would if we had wisdom to begin with.

August 17, 2012 8:33 am

Nothing in the article even trying to correlate temps to the droughts. Anyone?

Grey Lensman
August 17, 2012 9:51 am

JOHN B, sorry your graffiti is a single cartouche, and it does not say Khufu. Royal cartouches were perfect, so it was not miss written. Watch the video, the drought was a surprise to the “experts” and it was global. Many civilisations fell. Can you imagine a 40 year drought?

Richard Keen
August 17, 2012 10:04 am

Jean Meeus says:
“The obliquity of the Earth’s axis reached a maximum of 24 deg 14′ about the year 7530 BC.
Presently, the tilt is 23 deg 26′. Can a difference of only 48′ result in a sensible effect on the climate of a region? Just asking.”
A few years ago when I taught climate at the University of Colorado I used the worksheet below as a class exercise. Math Symbols come out as  in this text entry, so in the worksheet,  means “star”, as in multiply, except 4 means 4th root, and T means “delta T”. I used 0.64 for the Albedo, and kept the magnitude of the Earth’s greenhouse effect constant at 33C. So you can copy the text, re-insert the symbols, and calculate the theoretical summer temperature for the North Pole. Got it?
So, if you keep the earth’s distance from the sun on June 22 constant and increase the obliquity by 49′, the summer temperature at the North Pole goes up 4.3C. If the distance changes to 0.94 AU and obliquity goes up 60′, the North Pole warms 12.56 degrees. So the polar summer response to small obliquity changes is substantial.
What would the climate effect of warming the North Pole by 4 (or 12) degrees in the summer be? Probably an ice-free arctic for summer and early fall, which would warm the arctic, reducing the equator-pole temperature difference, shrinking the polar votex, allowing the tropical rain zones to expand northward. That would increase rainfall in the headwaters of the Nile, increasing river flow.
Just speculating.
What is the Earth’s distance (R) from the Sun on July 1, in Astronomical Units (A.U.) ?
Step 1: Determine the solar flux (S) at the Earth’s distance from the sun.
S = 1370 W/m2 / R2 =
The albedo of the north polar region is A =
The tilt (or obliquity) of the Earth’s axis today is Tilt = degrees. Sin (Tilt) =
Step 2: The amount of solar radiation absorbed by the Arctic is E = S(1A) sin(tilt), where 1A is the fraction of the solar flux absorbed by the ground, and the trig function sin(tilt) accounts for the spreading of the sunlight over a larger area due to the low angle of the sun. At the North Pole, the sun shines on the ground at the same angle 24 hours a day, so the average rate at which energy is absorbed by the ground in this Arctic region during the summer is
E = S(1A)sin(tilt) =
Step 3: The “Effective radiative temperature” of the Arctic (Te) today is:
Te = 4E / 4sigma = 4E / 0.01543 =
The magnitude of the Earth’s Greenhouse Effect is Tg =
Step 4: The actual surface temperature of the Arctic (Ts) equals the Effective radiative temperature (Te) plus the Greenhouse Effect (Tg): Ts = Te + Tg =
Convert the Surface Temperature to oC: Celsius = Kelvin – 273.15 =
[Something dropped at the last? Robt]

August 17, 2012 10:10 am

The cycles to which you refer are called Dansgaard-Oeschger Events during glacial phases or Bond Cycles during the present interglacial:
A popular book on the subject:
Please see also Heinrich Events:

August 17, 2012 10:12 am

This should be interesting read, “The long summer – how climate changed civilization” by Brian Fagan.

Gale Combs
August 17, 2012 10:36 am

Luther Wu says:
August 17, 2012 at 4:26 am
If we could determine what triggered the droughts…
Hope we aren’t “due” for another, although folks might think we’re already in one, in this neck of the woods.
There is also Dr. Joan Feynman’s Study of the Nile valley.

NASA Finds Sun-Climate Connection in Old Nile Records
….. analyzed Egyptian records of annual Nile water levels collected between 622 and 1470 A.D. at Rawdah Island in Cairo. These records were then compared to another well-documented human record from the same time period: observations of the number of auroras reported per decade in the Northern Hemisphere….
“Since the time of the pharaohs, the water levels of the Nile were accurately measured, since they were critically important for agriculture and the preservation of temples in Egypt,” she said. “These records are highly accurate and were obtained directly, making them a rare and unique resource for climatologists to peer back in time.”
A similarly accurate record exists for auroral activity during the same time period in northern Europe and the Far East. People there routinely and carefully observed and recorded auroral activity, because auroras were believed to portend future disasters, such as droughts and the deaths of kings…
The researchers found some clear links between the sun’s activity and climate variations. The Nile water levels and aurora records had two somewhat regularly occurring variations in common – one with a period of about 88 years and the second with a period of about 200 years.
“The Nile River provides drainage for approximately 10 percent of the African continent. Its two main sources – Lake Tana in Ethiopia and Lake Victoria in Tanzania, Uganda and Kenya – are in equatorial Africa….
The authors suggest that variations in the sun’s ultraviolet energy cause adjustments in a climate pattern called the Northern Annular Mode, which affects climate in the atmosphere of the Northern Hemisphere during the winter. At sea level, this mode becomes the North Atlantic Oscillation, a large-scale seesaw in atmospheric mass that affects how air circulates over the Atlantic Ocean. During periods of high solar activity, the North Atlantic Oscillation’s influence extends to the Indian Ocean. These adjustments may affect the distribution of air temperatures, which subsequently influence air circulation and rainfall at the Nile River’s sources in eastern equatorial Africa. When solar activity is high, conditions are drier, and when it is low, conditions are wetter….

The abstract to the actual paper Title: Is solar variability reflected in the Nile River?
There is also Chiefio’s Of Time and Temperatures looking at ~ 1500 yr bond events and the demise of civilizations.
And this following paper on the ~ 1500yr cycle. (Chiefio thinks we are now due for Bond Event Zero and the LIA was a minor Intermediate Period Half Bond Event Also see his 8.2 Kiloyear Event and You )

The Physical Evidence of Earth’s Unstoppable 1,500-Year Climate Cycle by S. Fred Singer and Dennis T. Avery
….It has long been accepted that the Earth has experienced climate cycles, most notably the 90,000-year Ice Age cycles. But in the past 20 years or so, modern science has discovered evidence that within those broad Ice Age cycles, the Earth also experiences 1,500-year warming-cooling cycles. The Earth has been in the Modern Warming portion of the current cycle since about 1850, following a Little Ice Age from about 1300 to 1850. It appears likely that warming will continue for some time into the future, perhaps 200 years or more, regardless of human activity. [This is where Chiefio disagrees]
Evidence of the global nature of the 1,500-year climate cycles includes very long-term proxies for temperature change — ice cores, seabed and lake sediments, and fossils of pollen grains and tiny sea creatures. There are also shorter-term proxies — cave stalagmites, tree rings from trees both living and buried, boreholes and a wide variety of other temperature proxies.
Scientists got the first unequivocal evidence of a continuing moderate natural climate cycle in the 1980s, when Willi Dansgaard of Denmark and Hans Oeschger of Switzerland first saw two mile-long ice cores from Greenland representing 250,000 years of Earth’s frozen, layered climate history. From their initial examination, Dansgaard and Oeschger estimated the smaller temperature cycles at 2,550 years. Subsequent research shortened the estimated length of the cycles to 1,500 years (plus or minus 500 years).

Dansgaard- Oeschger oscillations or warm events during glaciation known as interstadials also occur at ~ 1500 yr intervals.

On the 1470-year pacing of Dansgaard-Oeschger warm events by Michael Schulz
The oxygen isotope record from the Greenland Ice Sheet Project 2 (GISP2) ice core was reanalyzed in the frequency and time domains. The prominent 1470-year spectral peak, which has been associated with the occurrence of Dansgaard-Oeschger interstadial events, is solely caused by Dansgaard-Oeschger events 5, 6, and 7. This result emphasizes the nonstationary character of the oxygen isotope time series. Nevertheless, a fundamental pacing period of ∼1470 years seems to control the timing of the onset of the Dansgaard-Oeschger events…. During this interval the spacing of the Dansgaard-Oeschger onsets varied by ±20% around the fundamental 1470-year period and multiples thereof. The pacing seems unaffected by variations in the strength of North Atlantic Deep Water formation, suggesting that the thermohaline circulation was not the primary controlling factor of the pacing period.

Timing of abrupt climate change: A precise clock by Stefan Rahmstorf
Many paleoclimatic data reveal a approx. 1,500 year cyclicity of unknown origin. A crucial question is how stable and regular this cycle is. An analysis of the GISP2 ice core record from Greenland reveals that abrupt climate events appear to be paced by a 1,470-year cycle with a period that is probably stable to within a few percent; with 95% confidence the period is maintained to better than 12% over at least 23 cycles. This highly precise clock points to an origin outside the Earth system; oscillatory modes within the Earth system can be expected to be far more irregular in period.

Droughts are often associated with cooler temperatures since the energy is not there to drive evaporation cycle. Also as the Feynman paper indicated you see a shift in the jet streams à la Stephen Wilde.

Daniel Jones
August 17, 2012 10:53 am

Over it’s long cultural endurance of ~3000 years one can only find small instances of sacrifice in Egypt’s history. Normatively speaking, Egyptian Religion does not have a debtor/debt sacrifice relationship of human or animal sacrifice, and for the philosophical traditions they produced: Neoplatonic, Pythagorean, and Hermetism further testify to this as well. Gnosis is the fundamental aspect of it’s Heno/poly/cosmo-theism.
For a good reference for this notion of how Egyptian’s understood the category sacrifice, please see David Frankfurter’s essay ‘Egyptian Religion and the Problem of the Category Sacrifice’ in Ancient Mediterranean Sacrifice published by OUP:

Richard Keen
August 17, 2012 11:07 am

Richard Keen says:
August 17, 2012 at 10:04 am
Convert the Surface Temperature to oC: Celsius = Kelvin – 273.15 =
[Something dropped at the last? Robt]
>>>Robt, no, nothing dropped. That’s the last line of the worksheet where you convert Kelvin to C.

Richard Keen
August 17, 2012 11:26 am

Richard Keen says:
August 17, 2012 at 10:04 am
A few years ago when I taught climate at the University of Colorado I used the worksheet below as a class exercise. Math Symbols come out as  in this text entry, so in the worksheet,  means “star”, as in multiply, except 4 means 4th root, and T means “delta T”.
>>> I should add also that 1A is 1-A , as in one minus Albedo. And, m2 and R2 are “meters squared” and “R squared”, but I bet most of you figured that one out.

Ian W
August 17, 2012 5:16 pm

David Ross says:
August 17, 2012 at 8:19 am
……”The Birds is not read in our schools anymore, but it did give us the phrase “cloud cuckoo land” : )

Which is always somewhat annoying as the phrase _should_ be “Cuckoo Cloud Land” _sigh_ no Aristophanes scholars left these days 😉 Like hearing people talk of protagonists or worse the main protagonists…. there can only be one protagonist supported by a deuteragonist and perhaps a tritagonist.

August 17, 2012 5:28 pm

Actually, the dating may be off by centuries.
The dating of Egyptian dynasties was first done by an Egyptian priest, Manetho, who padded the list using the fact that many pharaohs had multiple names (given name, throne name, etc.) so listed many of them more than once. That was (and still is) considered the gold standard of ancient chronology, and so even the C-14 dates were adjusted to fit that record.
Yes, there was a major drought, that lasted years, around 1800 BC. This could very well be the drought for which the researchers are finding evidence. Egypt survived that drought thanks to their first grand vizier, Imhotep, who was not a native Egyptian, rather an “Asiatic” who lived to 110 years old. His native name was Joseph. Later Egyptians corrupted his memory.
Because of other research that I do, I repeatedly have to deal with this corrupted history (even though I’m not a historian), and it makes it harder for me to report my findings.

August 18, 2012 12:43 am

Best I’ve been able to figure it out, there was a large “rock fall from space” about 2200 BC / 2000 BC related to the Taurid Meteor / Comet Encke breakup. A LOAD of ancient cities and civilizations all “go poof” at the same time. (And it isn’t dated off pharaoh lists. Lots of ‘stuff in the ground’…)
Sadly, we don’t get to breathe a sigh of relief over this. The debris is subject to orbital resonance effects that concentrate a “lump” in the debris fields. Most of the mass is still up there. So we get pretty good Taurid meteor displays every year, but the mutual timing of: earth intersection with the “lump” being where we are; only comes around about once every 3000 years. (It’s a little more complicated in that there are really two major streams and two lumps with a couple of hundred years offset, so we get a double tap – part of why it is BOTH 2000 BC and 2200 BC…)
Separately, there is a 1500-1800 year Bond Event / DO event cycle that is most likely related to lunar resonance effects (but could have a cross relationship with the Taurids as both are “coordinated” by the same orbital resonance effects).
There is also some impact on a 180 or so year cycle from solar changes. These three things interact to cause much of the natural variation ( though on a longer term, changes of axial tilt and orbital circularity along with precession of the equinox, causes ice age glacials to come and go).
So where are we now? We’re on the edge of the Taurid stream and don’t get back to the middle until about 2300. The sun is in a ‘cool phase’ (‘sleepy sun’) but sans the added dust and stuff from a thick Taurid blanket may not have enough to make a full on Bond Event. So it’s a bit of a ‘dice roll’ for “this cycle”. Timing for “now” is pretty good on the 1470 year repeat, but sometimes it’s more of an 1800 year repeat – or 2300 A.D. ( The 1500 year cycle is an average of what looks like 2 nodes – one of which is 1800 or so years). But since we don’t know how much stuff is in the streams nor just how it is bunched up, the exact “when” of much bigger comet / meteor storms is a rough estimate…
So I think we’re “up for” a Bond Event “now”, or in 2300 A.D., depending on how much the Taurid contribution matters… But even if this time is a ‘skip beat’ to 2300 time, there are often periods of modest drought and famine on the 180 year cycle points when we get low solar contribution. It’s not very precise ( the data have lots of confounders, so some famine is caused by cold, but some by wars or political things). The Great Famine of 1315 A.D. lands on a low solar cycle… as do some famines with dates like 17 A.D. and 400 AD. But there are also some ‘misses’ so it’s not a great match.
One thing that is Very Clear when you start looking at history and weather together: Things Change all the time and far far more than we’ve seen in the last 100 years. Sometimes rapidly and dramatically. There’s a very thick dust layer in the sediments from Egypt to Iran for that 2000 BC event. It has onset in weeks to months, not years; then stays for decades… up to 200 years. Just as rapidly, the sediments go back to normal mud…
And this did not just happen once. There is a roughly 2000 year sequence of them ( the 8.2 Kilo Year Event, the 5.9 Kilo Year Event, this one in 2000 BC or 4000 Year Event B.Present, then the famine of 17 A.D. and / or the start of the Dark Ages in 540 AD. And if the 540 AD event was ‘the biggy’, then add 1500 to it and you get 2040 A.D. as the next one…
BTW, just prior to those major cold ‘dips’, there is typically a run up to a much warmer period… Heinrich Events being very strong examples ( if more rare as they show up during the Ice Age Glacials…) So everything about the present is perfectly normal. Including our pleasant very comfortable reasonably warm times. But it won’t last. We will have the inevitable turn back to cold again. Just like all the other times… The overall profile of the Holocene is a peak in temps about 8 ky ago, then a ‘wobbly down’ since. We get excited about the ‘wobbles’ (and right now the wobble is ‘up a little bit’ out of the Little Ice Age) but the overall trend is slowly downward into the next glacial. We’ve got about 2000 more years, max, to the start of persistent ice accumulation up north… Axis tilt and precession are already in the “cool off’ position and getting more so. It’s only a matter of time once that stage is reached.
But a tiny bit of geologic time ( 1 to 2 thousand years ) is an eternity for a politician, so ignored… Heck, even the 30 years of cooling from 1940 to 1970 was ‘almost forever’ and we had “new ice age coming’ scares then. Then we were in the other half cycle from 1970 to 2000 and had the Global Warming Scare. Now the PDO has swapped and the sun has gone sleepy and they are trying to mutate it to a “Climate Chaos” scare. It’s just a tiny little wiggle on a 1500 year wobble on an 8,000 year slide into a glacial…

wayne Job
August 18, 2012 3:14 am

Succinct as always Mr Smith thank you, your ponderings are always enlightening.

Chris Wright
August 18, 2012 4:00 am

I have a printout of an ice core record, it might be GRIP2.
When I look at the point corresponding to the demise of a great civilisation such as the Mayans, it corresponds almost uncannily to a significant sustained cold period in the ice core record.
The same applies to the end of the Egyptian Old Kingdom. The plot shows the temperature falling steadily from 2400 BC to 2000 BC, which correspomds perfectly to the mega drought of 4200 BC referred to above. And it corresponds perfectly with the death of the Old Kingdom.
It does seem that history confirms a very obvious and unsurprising truth: that mankind prospers when the world gets warmer, and that when the world gets colder people starve and civilisations fall.
Perhaps Gore, Hansen and Mann should take note….

Chris Wright
August 18, 2012 4:03 am

The line should have read:
The plot shows the temperature falling steadily from 2400 BC to 2000 BC, which correspomds perfectly to the mega drought of 4200 years ago referred to above.

August 18, 2012 5:49 am

Yes, the climate DOES change in unpredictable and extreme ways. New York and Chicago are in locations that were under an ice sheet 5,000 feet thick. (And who’s to say the world wasn’t a better place for it!) What really worries me is that there may be a significant climate change coming and those damn fools in Washington DC have bankrupted us. (Not to mention every place else where Progressives have taken hold, e.g. Greece, Detroit, and California.) If there is a major climate change we will not be prepared to deal with it.
Steamboat Jack (Jon Jewett’s evil twin)

August 18, 2012 8:10 am

Grey Lensman, Sorry but you are thinking of the wrong grafitti on the wrong pyramid.

August 18, 2012 8:15 am

cui bono says:
August 17, 2012 at 5:58 am
“Yaggh! Wrong link for some reason. Here’s the real one:”
Terrible BBC docu. 90 % filler with atrocious music and sound effects. Basically they say a Bond event wiped out the Old Kingdom – and in typical Orwell fashion, the BBC woman never calls it a cooling event but only a “climate change catastrophe”, again and again and again. The alarmists at the BBC, schooled by futerra to push the fear of climate change, at their very worst.
At 30:00 a short snippet with the late Dr. Bond, that was what made it worth sitting through it anyway. But they really gave me a hard time.

August 18, 2012 7:53 pm

@ David Ross
“The Birds is not read in our schools anymore”
Not a lot is.

Ulric Lyons
August 19, 2012 9:51 am

E.M.Smith says:
August 18, 2012 at 12:43 am
“So I think we’re “up for” a Bond Event “now”, or in 2300 A.D.,”
Seeing as the period in discussion starts with severe cooling from around 2279 BC:
I would expect a similar cluster of cold events starting some 4627yrs later, from around 2348 AD.

Interstellar Bill
August 22, 2012 10:12 am

I love the way they conflate past ‘climate change’ (i.e., natural variability)
with their current warmist bugaboo with the deceptively same label.

August 24, 2012 7:56 am

Mike M says:
August 17, 2012 at 7:25 am
This study puts even more impetuous on finding out more precisely just how far ‘more violent’ it was.

Heh. Why would it be impulsive and irresponsible? (impetuous)
“Impetus”, I think.

August 24, 2012 8:15 am

davidmhoffer says:
August 17, 2012 at 8:33 am
Nothing in the article even trying to correlate temps to the droughts. Anyone?


AJB says:
August 17, 2012 at 6:11 am
Article on BBC site entitled “The Fall of the Egyptian Old Kingdom” by Professor Fekri Hassan:

Relevant excerpt:

the initial breakdown of the Old Kingdom was caused by a sudden, unanticipated, catastrophic reduction in the Nile floods over two or three decades. This was so severe that famine gripped the country and paralysed the political institutions.

Climactic change
One of the greatest legacies of the Egyptian Old Kingdom © The scale of the failure of the floods is shown by the fact that the Faiyum, a lake of some 65 metres deep, dried up. This means that the lake actually evaporated over time. These low floods were related to global climatic cooling which reduced the amount of rainfall in Ethiopia and East Africa. In Iceland, researchers have detected a transition from birch and grassland vegetation to arctic conditions in about 2150 BC. This correlates with a shift to drier climate in south-eastern Europe c.2200 – 2100 BC.

As my email sig sez: “Warming: More Life. Cooling: More Death

August 24, 2012 11:58 am

Just noticed. That excerpt titles the climate passage “Climactic” change. I guess it really was climactic climatic change …

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