Climatic Events that Changed the World

The 8.2k yr BP climate event

Did the dramatic climate change in 6200 BC, known as the 8.2k yr BP event, affect people's lives? How did they cope? Are there any lessons to be learned to help us deal with climate change today? This article looks at the lives of the people that lived in the countries of the Mediterranean basin over this crucial period.

By Nick Nutter | Last Updated 2024-01-29 | Climatic Events that Changed the World

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What was the 8.2k yr BP climate event?

The 8.2-kiloyear BP event was a sudden global cooling episode that occurred approximately 6200 BC, disrupting the Earth's climate for two or three centuries with longer consequences in some areas. The event is attributed to a massive influx of freshwater into the North Atlantic, primarily from the draining of proglacial lakes formed by the retreating Laurentide Ice Sheet. This influx of freshwater disrupted the Atlantic Meridional Overturning Circulation (AMOC), a vital ocean circulation pattern that transports warm water northward, leading to a significant cooling across the North Atlantic and Mediterranean regions and beyond.

Different areas were affected at different times and in different ways, some became cooler and drier, some cooler and wetter. North Africa and Mesopotamia experienced a sudden period of aridity and cooling. Far west, in the Iberian Peninsula, summers became notably drier. Along the northern coasts of the Mediterranean, some areas were barely affected, whilst others changed dramatically.

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Human Behaviour at the Time of the 8.2k yr BP event

This article is not about proving that a significant climatic event caused a change in the behaviour of humans, rather to highlight how societies or human behaviour changed, if at all, whilst these climatic events were occurring or immediately afterwards. Of course, you may conclude that one did indeed cause the other and that the trajectory taken by humans after the 8.2k BP event would have taken a different course if that climatic event had not taken place. As ever, change provides opportunities for some and is bad news for others. We shall start our examination of human actions in Mesopotamia and then move west, north, and south.

Western Asia

In Western Asia the drought only lasted three hundred years. The net result was an influx of people into the Nile Delta and Lower Egypt region from the Fertile Crescent. Neolithic villages emerged throughout the Lower Nile and Egypt belatedly adopted Neolithic practices.

Within Mesopotamia itself, we see the beginnings of irrigation and the first evidence of surplus grain storage.

At Tell Sabi Abyad, in northern Syria a cultural change took place around 6200 BC, involving new types of architecture, including extensive storehouses and small circular buildings (tholoi); the development of pottery into many complex and often decorated shapes and purposes; the introduction of small transverse arrowheads and short-tanged points; the abundant occurrence of clay spindle whorls, suggestive of changes in textile manufacture; and the introduction of seals and sealings as indicators of property and the organization of controlled storage of surplus grain.

The Levant

As we approach the 8.2k yr BP event in the Levant, the Neolithic ways of life were long established in the lowlands, whilst hunter gatherers remained in the highlands. The boundaries between the two are blurred with the products of the hunter passing into the Neolithic settlements in exchange for cereals, sheep and goats. Between 7200 and 6700 BC, mega sites in the Jordan valley, such as Ain Ghazal in the north and Basta in the south had grown to 10 – 14 hectares with several thousand inhabitants supported by numerous small settlements in the surrounding areas. Milk and cheese were being produced as secondary products. The future looked bright, at least for those lucky enough to be at the top of the food chain, until about 6700 BC, five hundred years before the 8.2k yr BP event, when the mega site societies started to collapse.

The reasons for the collapse have been cited as soil erosion due to tree felling, an unsustainable or overbearing hierarchy (implying civil unrest), over grazing by goats and sheep, a lessening of central power over ritual and imported exotic goods as communities expanded into other areas, an ever more sybaritic lifestyle becoming, in the end, untenable (reminiscent of the fall of the Roman Empire?), or any combination of these factors. The 8.2k yr BP event would only have been the final nail in the coffin. That certainly appears to be the case at Jericho where a peculiar society, one that kept the heads of deceased relatives by plastering the skulls and painting the features of the person on it and then keeping them in the home, disappeared about 6000 BC. Jericho was abandoned for a thousand years.

By the time the 8.2k yr event registered, the mega site populations were already dispersing into small settlements in various ecological niches. Some in the drier landscapes started to practice mobile herding and penetrated into Sinai and the Negev, replacing the hunter gatherers by about 6000 BC. Coastal sites opened up from Atlit Yam (now at a depth of 8 – 12 metres and 200 – 400 metres offshore) in the north to Askelon in the south. These sites started to exploit the marine environment by deep diving for shellfish and deep-sea fishing from boats for trigger fish. In other words, fortuitously perhaps, these people were already taking actions that would allow them, in a reduced form, to survive the 8.2k yr event. The Levant was shaken but not stirred.

Cyprus

Cyprus presents us with an enigma. The island has been occupied since the 10th millennium BC. On the face of it, Cyprus is large enough and with enough geographical diversity, plus a long coastline with many opportunities for fishing (in fact Cyprus fishing canoes did venture forth and catch shark and hake), that the introduction of agriculture should have ensured a thriving community. Neolithic practices were introduced on to the island at an early stage, about 8000 BC, together with an array of animals including pigs/wild boar, sheep, goats, and cattle. Over the following 1400 years or so, all these species had to be replenished at least once from the mainland and some up to eight times. Cattle disappeared altogether during the early seventh millennium (too early for the 8.2k event to have been the cause), not to be replaced for four thousand years. Persian fallow deer (also introduced to the island) became a source of meat.

At the end of the seventh millennium BC, the society on the island is epitomised by an archaeological site at Khirokitia. The people there cultivated cereals, lentils, beans, peas, and a kind of plum called Bullace. Their animals were sheep, goats, and pigs. Pottery had not been developed and stone vessels were made of andesite. Hunting and the gathering of native plants such as pistachio nuts, olives and figs supplemented the diet. Houses were round and made of mudbrick on a pebble foundation. The settlement, with an area of about three hectares, was protected by a wall 2.5 metres thick and over 3 metres high. This, the earliest known culture in Cyprus, consisted of a well-organised, developed society. There were around twenty similar, although smaller, villages scattered around the island. For whatever reason, the villages were abandoned between 6200 and 6000 BC and the populations dispersed. Until recently it was thought that the island was abandoned for the following 1500 years but recent excavations at a necropolis near Limassol are indicating that a much-reduced population continued to exist on Cyprus.

Anatolia

In Anatolia, modern day Turkey, the 8.2k BP event resulted in drier summers and a general cooling during the entire year. The Neolithic city of Çatalhöyük had been populated since about 7500 BC. The city’s economy was based on the domestication of sheep and cattle and the cultivation of wheat and barley, peas, almonds, pistachios, and fruits.

By studying fat deposits left in ceramic pots, archaeologists have found that, about 6200 BC, the people of Çatalhöyük changed from a dependency on cattle to more sheep and goats, the latter two being better able to cope with drier conditions. They also found signs of malnutrition in cattle bones from this period.

Interestingly, the coastal town of Mersin, now a popular holiday destination, was founded about 6200 BC as the climate was changing. Perhaps the agriculturalists inland started to supplement their diet with produce from the sea.

The Balkans Neolithic Advance Halted

The Neolithic package spread out of the Fertile Crescent after about 9500 BC. It had reached southern Anatolia by about 8200 BC. There is a hiatus then until about 6700 BC after which the Neolithic advance gains a head of steam and archaeologists argue for a rate of advance by land and sea of about one kilometre per year. Now that does give the impression of a steady progression whereas it would have been anything but. It is more likely that a step forward was taken when population growth in the already cultivated areas became close to unsustainable, maybe once per generation.

That is until the end of the seventh millennium BC when the advance appears to falter around the Balkans and Aegean Sea. Sometime around 6200 BC, the Neolithic advance halted for a couple of hundred years at the gateway to the Balkans, around the Sea of Marmara, and the Dardanelles. Archaeologists have argued that hunter gatherer tribes resisted the Neolithic people and there may be some traction in this. A band of hunter gatherers is more easily able to adapt to changing climate, if only by moving to a new area – a la the Muge shell midden people, than more sedentary farmers and pastoralists. The 8.2k event created drier and cooler conditions in the Balkan area, possibly enough to reduce crops, thus reducing population growth and consequently the need to push forwards for a couple of hundred years. The pause would also have allowed the plants brought from the fertile crescent to acclimatise and adapt to new climates and growing conditions caused by the 8.2k BP event.

Apennine Peninsula

In Italy, some scholars have proposed that the so-called 8.2 k yr BP cooling event could have hindered the spread of farming beyond the Aegean zone until wetter climatic conditions occurred. Although this hypothesis seems to be corroborated by a rapid increase of population in Italy from c 6000 BC a precise causal link between climate and the introduction of farming in the Italian peninsula needs to be further investigated and could be the result of the interplay of different factors (climatic, social, demographic, economic). In addition, the available paleoclimate records show that Italy experienced gradually wetter climatic conditions from 6500 BC to 5000 BC and the so-called 8.2 k yr BP event could have had only a minor impact.

Iberian Peninsula

The Neolithic front line was still thousands of miles to the east of the Iberian Peninsula when the 8.2k BP event occurred. Mesolithic hunter gatherers thinly populated favoured areas. One such favoured area was the Atlantic coast between Lisbon and Nazare, an area that has benefited from many studies due to the proximity of the Muje shell middens a few kilometres inland of Lisbon in the valley of the river Tejo. The sites are mainly along the modern coast, between Lisbon and Peniche, and on the highlands of the Serra dos Candeeiros and d’Aires. The sites are open air on the coastal stretch, while inland there are both open air (mostly in the Rio Maior area on the eastern base of the mountain range), and caves and rock shelters both on the lowlands and highlands of the “Sierras.” These sites tend to be small (between 100 and 200 m2) and represent single occupations.

It is thought that the coastal ecosystems were altered due to diminution in upwelling with declining availability of marine resources, rapid sea level rise, and changes in coastal morphology because of the 8.2k BP event.

About 6200 BC, the shell middens were founded, and the Mesolithic tribes moved to the Muje and Sado river estuary areas where they established semi-permanent or even permanent occupation sites. The radiocarbon data strongly suggest that the first shell middens, probably Cabeco da Arruda, and the arrival of salt water took place around 8200 cal BP, and thus are coincidental with the 8.2 kyr cal BP event.

The use of shell middens gradually declined during the Early Neolithic period, between around 5,000 and 3,500 BC. This shift coincides with the introduction of farming and animal domestication, which provided new sources of food and shifted settlement patterns away from coastal environments. By the Middle Neolithic period, around 3500 BC, shell middens had largely ceased to be used.

Beyond serving as a repository for discarded shells, Portuguese shell middens played a multifaceted role in the lives of Mesolithic communities.

The middens provided a convenient location for processing shellfish. The shells were often broken open using stone tools, and the meat was extracted and consumed.

The middens served as communal gathering places, where people could socialize, engage in activities like tool making and maintenance, and conduct rituals.

Some Portuguese shell middens, particularly those in the Muge region, also functioned as burial grounds. Mesolithic individuals were interred within the middens, likely reflecting their symbolic importance to the community.

North and East Africa

In North Africa, the archaeological record shows a sudden period of cooling and drying about 6200 BC, whilst in East Africa the event presaged five centuries of drought.

However, the subsistence strategies of the Iberomaurusian hunter gatherers that had filtered into the Sahara region from the north and the black Africans who had worked their way from the southern fringes of the Nile, north and west to the Saharan central massifs, following an ever greener Sahara was radically different to that of the rest of the Mediterranean basin.

They initially existed by hunting the big game, aurochs, wild boar, (both originated in Eurasia and had long gone native), buffalo, giraffe and elephants found in abundance over what was a very different Sahara to that of today and fishing in the fresh water lakes such as Lake Mega Chad. They lived a semi sedentary life and invented pots long before the rest of the Mediterranean people. During the eighth to seventh millennium BC, they conducted experiments in wild animal husbandry.

In Tunisia and eastern Algeria, a group known as the Capsians created massive middens that contained animal bones and colossal quantities of land snail shells to rival those of Portugal. They were fairly sedentary in a rich environment, hunting hartebeest, aurochs, and zebra as well as the famous snails, to which they sometimes added wild onions for extra flavour.

During the late seventh millennium BC, these people turned to smaller game, gazelle, and hares. Even the snails were reduced in size, a consequence of the drier conditions brought on by the 8.2k BP event?

Conclusions

It is impossible that any human on the planet in 6200 BC would have been aware of the causes of the 8.2k yr BP event. However, the sudden nature of the event, whose effects would have been discernible well within one lifetime, would have been very apparent.

If the changes to human behaviour that occurred in different places at about the 6200 BC mark are anything more than coincidence, then we can only conclude that the 8.2k yr BP event did impact peoples lives and way of living. For the hunter gatherers, the response if any, was to remove themselves to more favourable environments and change their hunting techniques. For the neolithic people the response was to invest in methods of saving surplus food and allow (or possibly encourage) plant species to adapt to a different climate. In the longest established neolithic communities we see the first indications of control over food surpluses.

We also see a tendency for Neolithic people to migrate to areas more favourable to agriculture.

In both cases, communities were forced out of their ruts and compelled to adapt in order to survive. People were forced to re-evaluate their lives and how they lived, as individuals and as a community. Some innovations, such as improved weaving techniques, warehouses to store surplus and irrigation systems were well within the technology of the day whilst the introduction of seals for instance, was a more radical development that would have to wait until about 3500 BC.

References

Bicho, Nuno & Umbelino, Cláudia & Detry, Cleia & Pereira, Telmo. (2010). The Emergence of Muge Mesolithic Shell Middens in Central Portugal and the 8200 cal yr BP Cold Event. Journal of Island & Coastal Archaeology. 5. 86-104. 10.1080/15564891003638184.
Broodbank, C. (2013) The Making of the Middle Sea. Thames and Hudson, London.
Cunha, M., & Cardoso, J. L. (2001). Mesolithic people from Portugal: an approach to the Sado ossuary series. Journal of Human Evolution, 41(1), 1-27.
Diniz, T. B., Ribeiro, A. P., Carvalho, A., & Bicho, N. (2014). Reconstructing mobility strategies and resource exploitation patterns at the Mesolithic shell midden of Cabeço da Amoreira (Portugal). Quaternary International, 337, 283-301.
Jackes, M. K., & Meiklejohn, C. (2008). Hunter-gatherer settlements in Portugal: a review of Mesolithic shell midden sites. In Hunter-gatherers of interior and coastal environments: archaeological studies in Portugal and western Iberia (pp. 31-57). Springer, Dordrecht.
Meiklejohn, C., Cunha, M., & Jackes, M. K. (2009). Mesolithic shell middens and human remains in Portugal: the state of the art. In Human remains in the archaeological record: interpreating the past from the present (pp. 273-292). Oxbow Books, Oxford.
Paço, A. C. (1938). Contribuição para o estudo da Pré-História da Bacia do Tejo. Lisbon: Livraria Bertrand.
Parker, S.E., Harrison, S.P. The timing, duration and magnitude of the 8.2 ka event in global speleothem records. Sci Rep 12, 10542 (2022). https://doi.org/10.1038/s41598-022-14684-y
Roksandic, M. (2006). Shell middens: a bioarchaeological perspective. Springer, New York.
Santos, F., Soares, A., Bicho, N., & Cunha, M. (1990). Le site de Cabeço da Amoreira (Muge): étude de l'industrie osseuse. Revista de Arqueologia, 12, 145-166.
Neolithic Climate Change https://www.ancient-origins.net/news-history-archaeology/neolithic-climate-change-0010544