The fall of the Roman Empire, and the equally (if not more) advanced Han, Mauryan, and Gupta Empires, as well as so many advanced Mesopotamian Empires, are all testimony to the fact that advanced, sophisticated, complex, and creative civilizations can be both fragile and impermanent.
… accumulated surplus is not evenly distributed throughout society, but rather has been controlled by an elite. The mass of the population, while producing the wealth, is only allocated a small portion of it by elites, usually at or just above subsistence levels.
Technological change can raise the efficiency of resource use, but it also tends to raise both per capita resource consumption and the scale of resource extraction, so that, absent policy effects, the increases in consumption often compensate for the increased efficiency of resource use.
…. appears to be on a sustainable path for quite a long time, but even using an optimal depletion rate and starting with a very small number of Elites, the Elites eventually consume too much, resulting in a famine among Commoners that eventually causes the collapse of society. It is important to note that this Type-L collapse is due to an inequality-induced famine that causes a loss of workers, rather than a collapse of Nature.
While some members of society might raise the alarm that the system is moving towards an impending collapse and therefore advocate structural changes to society in order to avoid it, Elites and their supporters, who opposed making these changes, could point to the long sustainable trajectory ‘so far’ in support of doing nothing.
Collapse can be avoided and population can reach equilibrium if the per capita rate of depletion of nature is reduced to a sustainable level, and if resources are distributed in a reasonably equitable fashion.
Nasa-funded study: industrial civilisation headed for ‘irreversible collapse’?
Natural and social scientists develop new model of how ‘perfect storm’ of crises could unravel global system
by Nafeez Ahmed
http://www.theguardian.com/environment/earth-insight/2014/mar/14/nasa-civilisation-irreversible-collapse-study-scientists
A new study sponsored by Nasa’s Goddard Space Flight Center has highlighted the prospect that global industrial civilisation could collapse in coming decades due to unsustainable resource exploitation and increasingly unequal wealth distribution.
Noting that warnings of ‘collapse’ are often seen to be fringe or controversial, the study attempts to make sense of compelling historical data showing that “the process of rise-and-collapse is actually a recurrent cycle found throughout history.” Cases of severe civilisational disruption due to “precipitous collapse – often lasting centuries – have been quite common.”
The research project is based on a new cross-disciplinary ‘Human And Nature DYnamical’ (HANDY) model, led by applied mathematician Safa Motesharrei of the US National Science Foundation-supported National Socio-Environmental Synthesis Center, in association with a team of natural and social scientists. The study based on the HANDY model has been accepted for publication in the peer-reviewed Elsevier journal, Ecological Economics.
It finds that according to the historical record even advanced, complex civilisations are susceptible to collapse, raising questions about the sustainability of modern civilisation:
By investigating the human-nature dynamics of these past cases of collapse, the project identifies the most salient interrelated factors which explain civilisational decline, and which may help determine the risk of collapse today: namely, Population, Climate, Water, Agriculture, and Energy.
These factors can lead to collapse when they converge to generate two crucial social features: “the stretching of resources due to the strain placed on the ecological carrying capacity”; and “the economic stratification of society into Elites [rich] and Masses (or “Commoners”) [poor]” These social phenomena have played “a central role in the character or in the process of the collapse,” in all such cases over “the last five thousand years.”
Currently, high levels of economic stratification are linked directly to overconsumption of resources, with “Elites” based largely in industrialised countries responsible for both:
The study challenges those who argue that technology will resolve these challenges by increasing efficiency:
Productivity increases in agriculture and industry over the last two centuries has come from “increased (rather than decreased) resource throughput,” despite dramatic efficiency gains over the same period.
Modelling a range of different scenarios, Motesharri and his colleagues conclude that under conditions “closely reflecting the reality of the world today… we find that collapse is difficult to avoid.” In the first of these scenarios, civilisation:
Another scenario focuses on the role of continued resource exploitation, finding that “with a larger depletion rate, the decline of the Commoners occurs faster, while the Elites are still thriving, but eventually the Commoners collapse completely, followed by the Elites.”
In both scenarios, Elite wealth monopolies mean that they are buffered from the most “detrimental effects of the environmental collapse until much later than the Commoners”, allowing them to “continue ‘business as usual’ despite the impending catastrophe.” The same mechanism, they argue, could explain how “historical collapses were allowed to occur by elites who appear to be oblivious to the catastrophic trajectory (most clearly apparent in the Roman and Mayan cases).”
Applying this lesson to our contemporary predicament, the study warns that:
However, the scientists point out that the worst-case scenarios are by no means inevitable, and suggest that appropriate policy and structural changes could avoid collapse, if not pave the way toward a more stable civilisation.
The two key solutions are to reduce economic inequality so as to ensure fairer distribution of resources, and to dramatically reduce resource consumption by relying on less intensive renewable resources and reducing population growth:
The NASA-funded HANDY model offers a highly credible wake-up call to governments, corporations and business – and consumers – to recognise that ‘business as usual’ cannot be sustained, and that policy and structural changes are required immediately.
Although the study is largely theoretical, a number of other more empirically-focused studies – by KPMG and the UK Government Office of Science for instance – have warned that the convergence of food, water and energy crises could create a ‘perfect storm’ within about fifteen years. But these ‘business as usual’ forecasts could be very conservative.
A Minimal Model for Human and Nature Interaction
by Safa Motesharrei (School of Public Policy, University of Maryland), Jorge Rivas (Department of Political Science, University of Minnesota), Eugenia Kalnay (Department of Atmospheric and Oceanic Sciences, University of Maryland)
http://www.atmos.umd.edu/~ekalnay/pubs/handy-paper-for-submission-2.pdf
やっぱり人類は滅亡することがNASA出資の調査で判明。資源浪費と貧富二極化で
ギズモード・ジャパン
http://news.livedoor.com/article/detail/8640922/
調査は「Human And Nature DYnamical （HANDY）モデル」をベースにしたもので、アメリカ国立科学財団が出資するSESYNCの応用数学者サファ・モテシャリ（Safa Motesharri ）氏を筆頭に自然・社会科学分野の科学者たちが領域横断的に行ったもの。
結果は論文審査のある理系の学術専門誌「Ecological Economics」に掲載中ですが、政策研究開発研究所事務局長のナフェーズ・アーメド博士（Dr. Nafeez Ahmed）がもっと分かりやすい言葉で英紙ザ・ガーディアンにまとめている。
＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿
ローマ帝国も、それに劣らず高度だった漢文明も、モーリャ王朝文明もグプタ朝文明も、数多あるメソポタミア帝国の文明も、みな崩壊した。これは高度に進化した複雑で創造性豊かな文明も、もろくて永久ではない何よりの証拠だ。（論文より）
研究班ではこうした過去の崩壊例から人間と自然の力学を調べ、文明衰退に大きな役割を果たした要因（つまり今の崩壊リスク特定に役立つ要因）を特定した。これが人口、気象、水、農業、資源だ。
以上の要因が相まって、資源浪費と貧富の差という2つの社会状況が生まれると、その文明は崩壊する。「過去5千年」の歴史の中で「文明崩壊の特徴や過程で中心的役割を担った」のはこの2つの現象だった。
今は貧富の二極化が激しく、それが資源浪費に直接繋がっている。このふたつを牽引するのが、先進国に多く住むエリートだ。
［…］ 積もりに積もった黒字は社会全体に均一に分配されず、一部エリートに支配されている。この富を生み出しているのは人口の大多数を占める大衆なのだが、その彼らにはエリートから富のほんの一部しか回ってこない。普通は必要最低限の生活を維持できるレベルか、それにほんのちょっと毛が生えた程度だ。（論文より）
技術で資源効率を高めれば資源枯渇の問題は解決できる、という人もいるが、人が人害を回避するため作った技術も結局は崩壊に繋がってしまう。
技術革新で資源使用効率を高めても、人口ひとりあたりの資源消費量と資源採取の規模も同時に増えてしまう傾向がある。そのため、有効な政策不在の状態では、消費が増えた分で資源使用効率を高めた分がチャラになってしまうことが多い。（論文より）
現に過去200年で農業も工業も生産性はかなり向上したが、それで「資源消費が減る」ということはついぞなかった。
様々なシナリオでモデルを組んだ結果、研究班は「今の世界の現実を反映した状況では崩壊回避は困難という結論に至った」。例えば1番目のモデルは「文明」。
持続可能な状態がだいぶ長く続くと思われているが、極一部のエリートの将来を枯渇スピードが一番緩いシナリオで占ってみても、エリートは浪費が行き過ぎて、平民に飢餓をもたらし、それが引いては社会の崩壊をもたらす。この種のLラインの崩壊は自然崩壊が原因で起こるのではなく、不平等が原因で飢餓が起こり、それが労働者喪失に繋がって起こる。これは頭に刻んでおくべき重要なポイントだ。（論文より）
「解決策は主に2つ。資源がもっと平等に配分できるよう、経済の不平等を減らすこと。資源負担の軽い再生エネルギーに依存し人口増加を抑制することで、資源消費を劇的に減らすこと」（論文より）