10 Climate change and civilisation collapse Dr Benny Peiser …

10 Climate change and civilisation
   collapse
       Dr Benny Peiser




   Like most things, collapse explanations are subject to fashion, and
   the one most in the limelight today is climatic change ... Right
   now mega-drought is the `hot' explanation for the Classic [Maya]
   collapse, and the usual bandwagon effect is in full career among
   many of my colleagues, although others remain properly
   suspicious of drought as the triggering mechanism.

                David Webster, The Fall of the Ancient Maya, London 2002



Introduction
One of the most powerful drivers of environmental gloominess and
cultural pessimism is the spectre of ecological apocalypse. The muta-
tion of age-old, religious end-time prophecies into secular predictions
of natural cataclysms and societal collapse ­ in short, the emergence
of environmental apocalypticism ­ is perhaps the most significant ide-
ological development in the western world since the demise of Marx-
ism.
    Marxist doctrine, let us never forget, crumbled because its pre-
dicted, and eagerly anticipated, disintegration of free market
economies never transpired, but communist economies and totalitar-
ian dictatorships have mostly come to sticky ends. Deeply infuriated
by the failure of their predictions and the unremitting vibrancy of cap-
italism, many disillusioned believers turned to ecological pessimism
and environmental determinism. Not for the first time in the long his-
tory of apocalyptic movements, new wine was poured into old bottles.
192   Adapt or Die



Many ideologues replaced their old beliefs in economic decline and
breakdown with the new principle of ecological decay and disaster.
   There is no shortage of physical factors that can produce natural
disasters and social deterioration. These could include catastrophes
due to asteroid and comet impact, the failure of global agriculture due
to volcanic super-eruptions, the reappearance of a new ice age, epi-
demic diseases, etc. However, none of these horror scenarios has
alarmed the public as much as the alleged peril of human-caused
global warming.
   Originally, this idea was a theoretical speculation about the sup-
posedly negative impact of increasing CO2 emissions into the earth's
atmosphere. Recently, these speculations have turned into a veritable
scare. We are warned that if we fail to drastically reduce CO2 emis-
sions, this will cause global warming which will trigger social up-
heaval and natural disaster everywhere. Some of the experts on
civilisation collapse have argued that dealing with climate change `will
require substantial international cooperation, without which the 21st
century will likely witness unprecedented social disruptions'.1
   This chapter argues that environmental determinism is the latest
fad in explaining past societal evolution and civilisation collapse. It is
beyond doubt that a number of complex societies fell apart during the
last 4,000 years. Climate change is one possible explanation for those
collapses, but no one has identified the basic dynamics or driving
forces of societal dissolution. Warmer periods have had a consider-
ably benign role in social, economic and technological progress, but
global cooling and cold spells have been largely detrimental to soci-
eties. Today, in contrast, we have the technological capacity to deal
with climatic changes, even with events that may have been cata-
strophic in the past.


Historical evidence for civilisation collapse
To further amplify the alarm that a warming climate would lead to
collapse of human civilisation, a number of researchers have turned
their attention to historical examples of societal breakdown and have
incriminated `climate change' for the disintegration of ancient soci-
eties.2 From the downfall of the Akkadian civilisation to the demise of
the ancient Mayans and the Roman Empire, climate change is increas-
ingly named as the cause of a number of ancient civilisation collapses.3
                        Climate change and civilisation collapse       193



    The discovery of warming and cooling cycles during the Holocene
­ the present geological era ­ has drawn attention to historical climate
events such as the Little Ice Age, a prolonged cold spell that affected
wide areas of the globe for several hundred years.
    There is increasing evidence that the climate in the Holocene era
has been much more variable than once believed. Abrupt climatic
downturns in the form of temperature decreases appear to have been
significant enough to cause agricultural disruptions and other adverse
effects in a number of historical cases. Warmer temperatures, on the
other hand, have never contributed to the decline or disintegration of
any society. Climate alarmists consistently fail to mention that warm
periods during the Holocene have played a considerably benign role in
social, economic and technological progress. Global cooling and cold
spells, on the other hand, have been largely detrimental to society's
advance and evolution.
    Throughout much of human history, cities, regions and entire
states have come and gone. The stability of agriculture-based societies
has always relied on the constancy of climatic conditions. Archaeo-
logical research has unearthed heaps of empirical evidence for the in-
herent vulnerability of agricultural societies to climatic change. Since
agricultural production relies on factors such as fertile soils, precipita-
tion or irrigation, prolonged climatic downturns, droughts or desicca-
tion have regularly led to mass migration and resettlement. Some
regions which were once inhabited 5,000 years ago (such as parts of
the Sahara) today are deserts ­ barren and abandoned.
    But relocation of a society does not necessarily mean the unmiti-
gated `collapse' of a society. Neither are episodes of climate changes
detrimental to all, or negative in all of their aspects. If a social group
abandons terrain which has become sterile, it is does not mean `soci-
etal failure' if they move to more fertile territory. In fortunate circum-
stances, the movement of social groups to new territory is beneficial
and can lead to higher levels of societal complexity.
    The desertification of the Saharan region 7000 to 5000 years ago,
for example, set in motion a significant advance in societal evolution.
It is now generally thought that the environmental pressure behind
these events may also have been the main impulse that led to the foun-
dation of complex urban civilisations along the Nile, Euphrat and
Tigris rivers.4
    In short, the evolution of society during the Holocene has been
194   Adapt or Die



marked by recurrent patterns of expansions and downturns. Some
cultural declines have been gradual, occurring over centuries, and oth-
ers have been more abrupt. Warfare, power struggles, diseases, over-
population, economic disruptions, droughts, or natural disasters can
facilitate a breakdown in social order and a decline in cultural com-
plexity. Internal causes (such as political conflicts or over-farming) can
combine with external causes (such as war or natural disaster) to
bring about malfunction and failure.
   There is unambiguous evidence that a number of urban civilisa-
tions which had once acquired high levels of social complexity (such
as the Akkadian, Roman and Mayan civilisations) declined and disin-
tegrated. Yet despite burgeoning research and mounting data, no one
has identified the basic dynamics or driving forces of societal dissolu-
tion. What we know for certain, however, is that every age has its own
favourite explanations for the collapse of civilisations before it. The
latest fad for such explanations is environmental determinism.


What wrecked the Roman Empire in the West?
Consider the decline and fall of the western Roman Empire. For cen-
turies, scholars have mulled over the possible reasons for its demise.
According to traditional assumptions, barbarian invasions which ran-
sacked Rome in AD 476 brought about the Empire's fall. The end of
classical civilisation came 100 years later after an epidemic of bubonic
plague swept the region, and invasions by Slavic tribes brought wide-
scale destruction.
    Ancient authors attributed the social decadences and Roman de-
cline to mounting bureaucracy and excessive taxation. Writers during
the Enlightenment (Edward Gibbon, for instance) favoured moral and
religious explanations and blamed Christian anti-paganism for
Rome's downfall. Marxist historians, on the other hand, preferred
economic and social factors, blaming class conflicts, political struggles
and imperial over-stretch.5 The emergence of the environmental
movement illustrates that the focus has shifted yet again. Rather than
considering internal and social factors, environmentalists prefer eco-
logical explanations, blaming population growth, environmental
degradation, deforestation or `climate change'.6
    Around AD 540, parts of Europe did indeed experience rapid cool-
ing. This period corresponds with worldwide accounts of a significant
                        Climate change and civilisation collapse     195



climatic downturn due to a mysterious dust-veil event.7 The cause of
this cooling is still unknown, but some researchers speculate that it
was either the result of a massive volcanic eruption or due to some
cosmic dust loading of the stratosphere. Tree-ring data from Europe
and North America indicate a significant temperature drop around
AD 536. They also show that the tree-ring widths returned to pre-AD
535 scale in the late 540s, suggesting that the climatic downturn
lasted for some fifteen years.8 Other research suggests that the cold pe-
riod began as early as AD 500 and lasted for more than 200 years.9
    Evidently, there is no consensus about the duration or cause of the
`European Dark Ages Cold'. Nor is there any agreement about
whether the Roman Empire tumbled because of a climatic downturn,
due to political and economic discord, or as a consequence of a mul-
titude of factors. After all, the onset of a cool period did not lead to
the crash of the Byzantine Empire, which survived for another 500
years. Thus, we remain in the dark about the real reasons why Eu-
rope's classical civilisation ended in the West but continued in the
East.


The fall of the Akkadian Empire
The Akkadian Empire dominated large parts of Mesopotamia during
the late third millennium BC. At some time between 2350 BC and
2200 BC, it disintegrated. Traditional explanations for its demise
range from warfare and internal rebellion to socio-political dissolu-
tion. In recent years, `climate change' has become the most popular
theory not just for the cessation of the Akkadian Empire, but for the
seemingly simultaneous collapse of other urban civilisations around
the world.
   A number of researchers are convinced that in 2200 BC, an abrupt
drop in global temperatures occurred that disrupted the weather
around the globe.10 One of these researchers, Yale University archae-
ologist Harvey Weiss, claims:

   The Akkadian empire of Mesopotamia, the pyramid-constructing
   Old Kingdom civilisation of Egypt, the Harappan 3B civilisation
   of the Indus valley, and the Early Bronze III civilizations of
   Palestine, Greece, and Crete all reached their economic peak at
   about 2300 BC. This period was abruptly terminated before 2200
196   Adapt or Die



   BC by catastrophic drought and cooling that generated regional
   abandonment, collapse, and habitat-tracking.11

Abrupt climatic downturns are not unusual since they repeatedly
occur in response to significant volcanic eruptions and other atmos-
pheric dust-loading events. The abrupt cooling in 2200 BC, however,
is thought to have disturbed agricultural production around the globe
for three centuries. This cooling is assumed to have triggered cata-
strophic sandstorms and mega-droughts, subsequently prompting so-
cietal disintegration on a global scale.12
    But how compelling is the case for 300-year-long sandstorms,
droughts and climatic disaster? What physical mechanism could have
triggered such a global calamity? So far, there have been no convincing
answers to these questions. In fact, there remain grave doubts within
the scientific community about this entire theory, particularly with re-
gard to its magnitude, its physical causation and its chronology.
    For a start, archaeological evidence seems to be irreconcilable with
its basic premises. Fifty years ago, French archaeologist Claude Scha-
effer discovered that most Near Eastern settlements had been repeat-
edly destroyed and abandoned throughout the 2000 years of Bronze
Age cultures (~3000­1200 BC). In short, the recurring destruction
and abandonment of Bronze Age settlements is the norm, not the ex-
ception, throughout the Near East. There also seems to be archaeo-
logical evidence for seismic activity at the end of the Early Bronze Age,
which would be incompatible with a simplistic climate model of civil-
isation collapse.13
    Even more doubts have been raised about the chronology of the
events in question. Marie-Agnès Courty, a leading team member of
the Tell Leilan excavations14 which formed the basis of the original
idea, has recently revised the dating of the `abrupt' onset of environ-
mental change to 2350 BC, thus shifting the date by some 150 years.15
Butzer16 and Baillie,17 two of the world's leading paleo-environmental
researchers, have highlighted the inherent imprecision of the dating
methods used.18
    In any case, the claim for an abrupt worldwide climatic downturn
in 2200 BC is difficult to sustain if such a global disaster does not
show up in the most sensitive and reliable climate indicator, Californ-
ian and European tree rings! Critics have thus underscored the elu-
siveness of any conclusions drawn from a still unreliable chronology:
                        Climate change and civilisation collapse     197



   Are we looking at an event starting in 2400 or 2350 or 2200 or
   2180? Butzer with his `2400­1900 BCE' has broadened the debate
   to a full half millennium ­ a time period so long that we could
   reasonably expect some environmental changes to be recorded in
   most areas.19

Other researchers have pointed out that certain civilisations, such as
the Bronze Age culture of the Mediterranean island of Crete, were not
at all affected by the hypothetical climate disaster.20 In fact, a number
of cities in the Near East and on the Indian subcontinent appear to
have expanded and progressed to higher social complexity during the
nadir of the supposed mega-drought.21
    Furthermore, advocates of the climate catastrophe theory have not
yet presented a coherent physical model that would provide an expla-
nation for an abrupt climate crash which persisted for 300 years. Even
American tree-ring data, which is cited as confirmation of the global
scale of the prolonged catastrophe, only shows a slow and gradual de-
crease in temperatures which returned to the pre-cold average in 2056
BC.22
    Regardless, many Akkadian settlements were abandoned after
2200 BC while people moved south, where irrigation-fed agriculture
continued. While the Akkadian state and its imperial bureaucracy
crumbled, elements of the culture itself relocated and lived on. And
not everyone fled the area since nearby settlements continued their ex-
istence at diminished levels. Nevertheless, the evidence for some sort
of natural calamity seems undeniable. While no one knows what
brought it about, its overall societal effects on Mesopotamia and the
Near East ­ let alone the rest of the world ­ are far from certain.


The Maya civilisation is dead, long live the Maya civilisation
The decline and fall of the Classic Maya civilisation around AD 800
is another popular case in point ­ climate change is blamed for its
demise. Modern-day ecological concerns such as population growth
and environmental degradation are frequently cited as the cause of the
Maya `collapse', but climate change has certainly become the most
popular culprit in recent years.
   Recurrent droughts and mega-droughts on the Yucatan Peninsula of
Mexico have been a persistent feature of Mesoamerican civilisations
198   Adapt or Die



for centuries. There is a wealth of paleo-environmental evidence that
local and regional climates have varied considerably during the last
10,000 years.23 In addition, there is ample evidence that Maya migra-
tions, the abandonment of settlements and societal `mini-collapses'
were recurring features of a highly volatile culture.
    According to a number of researchers, the event which triggered
the Classic Maya `collapse' was an abrupt climatic incident and a pro-
longed drought that began early in the ninth century AD. In keeping
with this scenario, food production dropped drastically as a result of
the mega-drought, resulting in large-scale famines. Ensuing endemic
diseases caused plagues and epidemics. In view of such chaos, the dis-
integration of social and political structures most probably con-
tributed to the breakdown.24
    The climate change hypothesis of Maya collapse includes a variety
of supposed causes, factors and effects. This multitude of suggestions
is not entirely new. It is actually characteristic of research on civilisa-
tion collapse. As early as the 1930s, two pioneering Mayanists pub-
lished a list of hypothetical explanations for the demise of the Classic
Maya which included climatic change, exhaustion of the soil, epi-
demic diseases, earthquakes, war, national decadence and religious su-
perstition. As David Webster points out, even after 70 years of
painstaking research, these are still the same basic assumptions for its
termination.25 Indeed, one Mayanist has claimed to have counted as
many as 100 distinct theories, explanations and hypotheses for the
Maya `collapse'.26
    More recently, the mega-drought hypothesis has received further
support with research that provides additional evidence of a hundred-
year drought punctuated by shorter but multi-year droughts at
around 810, 860, and AD 910.27 According to this theory,

   rapid population expansion during a climatically favourable
   period from about 550 to 750 AD left the civilisation operating at
   the limits of the environmental carrying capacity. This left the
   Mayan society highly vulnerable to subsequent multi-year
   droughts and led to its collapse.28

The very term `civilisation collapse' may be altogether inappropriate,
however, or at least misleading. The Maya culture was neither finished
for good, nor were all of its settlements abandoned at the end of the
                         Climate change and civilisation collapse        199



Classical period. Some regions show clear evidence of the continuity
of Maya occupation and culture. These areas were mainly located in
the northern plain of Yucatan and inland around a chain of lakes.
Many Maya migrants, it would appear, fled the droughts and resettled
where water sources were still readily available. It was in these settle-
ments that the Spanish discovered a highly complex Maya society
when they arrived in the sixteenth century.


The fall of complex and the rise of hyper-complex civilisations
Whatever the details of societal decline and disintegration in antiq-
uity, it is beyond doubt that a number of complex societies fell apart
during the last 4000 years. Such temporary breakdowns, however,
have never been unmitigated or total. Most unsuccessful ancient soci-
eties recovered after a period of marked decline and regularly emerged
more robust and dynamic. After all, the general trend of cultural evo-
lution during the last 10,000 years has not been intermittent break-
down of societies but relentless technological progress, increased
social complexity and much improved safety measures against the
forces of nature.
   The imagery of powerful civilisations breaking down has nonethe-
less contributed to a mindset which is increasingly fretful about the
fate of our own civilisation. All too often, these worries are based on
misleading analogies with agricultural societies that were especially
vulnerable to environmental stress and lacked the benefits of modern
technologies to cope with changes.
   According to climate alarmists, predicted global warming will
cause even more unstable conditions in our modern world which
might be populated by up to 10 billion people in a few decades. This
reasoning suggests that today's `overcrowded earth' may hamper such
adaptation:

   The magnitude of expected temperature changes gives a sense of
   the prospective disruption. These changes will affect a world
   population expected to increase from about 6 billion people today
   to about 9 to 10 billion by 2050. In spite of technological changes,
   most of the world's people will continue to be subsistence or
   small-scale market agriculturalists, who are similarly vulnerable to
   climatic fluctuations as the late prehistoric/early historic societies.
200   Adapt or Die



   Furthermore, in an increasingly crowded world, habitat-tracking
   as an adaptive response will not be an option.29

Contrary to popular belief, the biggest climatic risk to the stability of
complex societies is not global warming, but global cooling, and the
potential risks this would pose to agricultural food production. While
such a natural disaster could be triggered by large asteroid impact or
a volcanic super-eruption, the probability that any such event will
occur in any given century is remote.30
    It would be unwise, though, to simply discard the idea of cata-
strophic climate change. Given the probable, albeit unproven, likeli-
hood that climatic downturns have contributed to the decline and
even downfall of past societies, we should consider just how vulnera-
ble our own civilisation might be to a recurring fall in temperatures.
    Climatic downturns, even much-dreaded abrupt cooling events, no
longer threaten society with agricultural catastrophes, nor will they
inevitably lead to societal decline and collapse. Genetic engineering of
crops and seeds already allows the development of cold-resistant
plants. In the future, biotechnology (e.g. using a gene from a cold-re-
sistant fish) will be able to produce cold-resistant crops that can grow
even in very cold climates. Genetic engineering has already increased
the natural defences of many crops and allowed them to survive
droughts and cold which are normally fatal to plants. There is no rea-
son to doubt that future crops will be designed to withstand even
drier, colder and saltier conditions.
    If these revolutionary developments do not reassure the alarmed
public, there has also been enormous progress in applying cloud-seed-
ing technologies to ameliorate the impact of periodic severe droughts
in a number of countries around the globe. These and other forth-
coming mitigation strategies would potentially give our civilisation
technologies that could enable us to survive climatic crises which an-
cient and simpler societies may have found overwhelming.
    Tomorrow's hyper-complex societies will be able to withstand pro-
longed droughts thanks to technological advances and economic effi-
ciency. While self-reliant, agricultural societies are essentially rigid
and extremely vulnerable to climatic stress factors, inter-connected
high-technology cultures are much better sheltered from possible cat-
astrophes, because of modern technologies and mitigation strategies.
    In fact, technological progress and bio-technological developments
                      Climate change and civilisation collapse   201



have been advancing to levels where the age-old fears of mega-
drought and mega-famine are gradually disappearing in most regions
of the world. Given the accelerating evolution of disaster-resistant
crops, weather engineering and other mitigation technologies, I hope
that before long we will also overcome climate angst based on histor-
ical analogies that no longer match up.
Notes
1    Weiss and Bradley (2001).
2    Weiss and Bradley (2001).
3    DeMenocal (2001); Mapes (2001).
4    Claussen et al. (1999).
5    Tainter (1990).
6    Pointing (1991).
7    Keys (1999).
8    Baillie (1999).
9    Berglund (2003).
10   Weiss (2000).
11   Weiss (2001).
12   Weiss et al. (1996); Weiss (2000).
13   Peiser (1998).
14   See http://research.yale.edu/leilan/ for more information about this project.
15   Courty (1998).
16   Butzer (1996).
17   Baillie (1998).
18   Butzer (1996) and Baillie (1998).
19   Baillie (1998).
20   Manning (1996).
21   Butzer (1996); Possehl (1996).
22   Weiss (2000).
23   Gill (2000).
24   Ibid.
25   Webster (2000).
26   Ibid.
27   Haug et al. (2003).
28   Webster (2000).
29   Weiss (2001).
30   Engvild (2003).



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