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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/267751719 Is Global Collapse Imminent? An Updated Comparison of The Limits to Growth with Historical Data Technical Report · August 2014 CITATIONS 25 READS 5,037 1 author: Graham Turner University of Melbourne 45 PUBLICATIONS 799 CITATIONS SEE PROFILE All content following this page was uploaded by Graham Turner on 04 November 2014. The user has requested enhancement of the downloaded file. 2 2 Is Global Collapse Imminent? An Updated Comparison of The Limits to Growth with Historical Data Research Paper No. 4 August 2014 About MSSI Research Papers MSSI’s Research Papers Series is a key communication initiative of the Melbourne Sustainable Society Insti tute, aimed at stimulating thought and discussion within the University of Melbourne and broader commu nity and showcasing the scholarship of MSSI. Editor Dr Lauren Rickards, Melbourne Sustainable Society Institute, Lauren.Rickards@unimelb.edu.au Author Dr Graham M. Turner is a Principal Research Fellow at the Melbourne Sustainable Society Institute, Univer sity of Melbourne, Australia. Acknowledgments This Paper draws substantially on the following publication, with additional material incorporated: Turner G 2012, On the cusp of global collapse? Updated comparison of the Limits to Growth with historical data. GAiA, 21, pp. 116-124. Citing this report Please cite this paper as Turner, G. (2014) ‘Is Global Collapse Imminent?’, MSSI Research Paper No. 4, Melbourne Sustainable Society Institute, The University of Melbourne. ISBN: 978 0 7340 4940 7 3 3 Abstract The Limits to Growth “standard run” (or business-as-usual, BAU) scenario produced about forty years ago aligns well with historical data that has been updated in this paper. The BAU scenario results in collapse of the global economy and environment (where standards of living fall at rates faster than they have historically risen due to disruption of normal economic functions), subsequently forcing population down. Although the modelled fall in population occurs after about 2030—with death rates rising from 2020 onward, reversing contemporary trends—the general onset of collapse first appears at about 2015 when per capita industrial output begins a sharp decline. Given this imminent timing, a further issue this paper raises is whether the current economic difficulties of the global financial crisis are potentially related to mechanisms of breakdown in the Limits to Growth BAU scenario. In particular, contemporary peak oil issues and analysis of net energy, or energy return on (energy) invested, support the Limits to Growth modelling of resource constraints underlying the collapse. 4 Checking on the Limits to Growth With over forty years of hindsight available since The Limits to Growth (LTG) was first published (Meadows et al., 1972, Meadows et al., 1974), it is timely to review how society is tracking relative to their ground-breaking modelling of scenarios, and to consider whether the global economy and population is on a path of sustainability or collapse. Over a similar timeframe, international efforts based around a series of United Nations (UN) conferences have yielded mixed results at best (Lin ner and Selin, 2013, Meadowcroft, 2013). In addition to unresolved critical environmental issues and resource constraints such as anthropogenic climate change and peak oil, the global economy is also beset by ongoing challenges from the Global Financial Crisis (GFC), not least of which are lingering levels of extraordinary debt. The standard political remedy of growing the economy out of debt has potential ramifications for environmental stability, with evident negative feedbacks on the economy. The intertwined economy-environment dependencies embodied in the original 1970’s LTG model ling provide an opportunity to examine how the global predicament has unfolded and what it might mean for the future. Through a dozen scenarios simulated in a global model (World3) of the environment and economy, Meadows et al. (1972, p. 125) identified that “overshoot and collapse” was avoidable only if consid erable change in social behaviour and technological progress was made early in advance of environ mental or resource issues. When this was not achieved in the simulated scenarios, collapse of the economy and human population (ie. a relatively rapid fall) occurred in the 21st century, reducing living conditions to levels akin to the early 20th century according to the modelled average global conditions. Exactly how this would play out in the real world is open to conjecture, as noted below. Despite the LTG initially becoming a best-selling publication, the work was subsequently largely relegated to the “dustbin of history” by a variety of critics (eg., Lomborg and Rubin, 2002). These critics perpetuated the public myth that the LTG had been wrong, saying that it had forecast col lapse to have occurred well before year 2000 when the LTG had not done this at all. Ugo Bardi’s The Limits to Growth Revisited (2011) comprehensively details the various efforts to discredit the LTG study. He draws parallels with documented campaigns against the science of climate change and tobacco health impacts. Three economists- Peter Passel, Marc Roberts, and Leonard Ross- initiated criticisms in a New York Times Sunday Book Review article in 1972. They made false statements (eg. “all the simulations based on the Meadows world model invariably end in collapse”), and also incor rectly claimed that the book predicted depletion of many resources by about 1990. The US econo mist William Nordhaus made technically erroneous judgements (in 1992) by focusing on isolated equations in World3 without considering the influence that occurs through the feedbacks in the rest of the model. In 1973 a critique of the LTG, edited by physicist Sam Cole and colleagues at the University of Sussex, contained a technical review of the World3 modelling and essays based on ideology that attacked the authors personally. According to Bardi, the technical review fails because it largely concerned how the World3 model could not be validated from the perspective of simple linear modelling, which is an inappropriate test for a non-linear model. The review also established that the model could not run backwards in time, though this is an unnecessary requirement for the model to run forward properly. Criticism of the study continued for about two decades, including other noted economists such as Julian Simon, along the vein of such misunderstandings and per sonal attacks. For the last decade of the twentieth century, however, criticism of the LTG centred on the myth that the 1972 work had predicted resource depletion and global collapse by the end of that century. Bardi identifies a 1989 article titled “Dr. Doom” by Ronald Bailey in Forbes magazine as the beginning of this view. Since then it has been promulgated widely, including through popular commentators such as the Danish statistical analyst Bjørn Lomborg, and even in educational texts, peer-reviewed literature, and reports by environmental organisations. 5 Over the last decade, however, there has been something of a revival in awareness and understand ing of the LTG. Most recently, Randers (2012a)—a LTG co-author—has published his forecast of the global situation in 2052 and renewed the lessons from the original publication (Randers 2012b). A turning point in the debate occurred in 2000 with the energy analyst Simmons (2000) raising the possibility that the LTG modelling was more accurate than generally perceived. Others have made more comprehensive assessments of the model output (Hall and Day, 2009, Turner, 2008); indeed, my earlier work found that thirty years of historical data compared very well with the LTG “standard run” scenario. The standard run scenario embodies the business-as-usual (BAU) social and economic practices of the historical period of the model calibration (1900 to 1970), with the scenario modelled from 1970 onwards. This paper presents an update on the prior data comparison by Turner (2008). An update is es pecially pertinent now because of questions raised about how the current economic downturn— commonly associated with the GFC—may relate to the onset of collapse in the LTG BAU scenario. Is it possible that aspects leading to the collapse in the LTG BAU scenario have contributed to the GFC-related economic downturn? Could it be that this downturn is therefore a harbinger of global collapse as modelled in the LTG? To provide context and convey the importance of understanding global dynamics, this paper first summarises the mechanisms that play-out in the modelled BAU scenario. Subsequently, the mod elled trajectory is compared with some forty-years of historical data (which are outlined in the ap pendix). The appendix also provides comparison of the data with two other scenarios, namely “com prehensive technology” and “stabilized world” scenarios (with full details in Turner, 2012)—showing that the comparison strongly favours the BAU scenario only. On the basis of this comparison, we discuss what the modelling might mean for a resource-constrained global economy. In particular, the paper examines the issue of peak oil and the link between energy return on investment (EROI) and the LTG World3 model. The findings lead to a discussion of the role of oil constraints in the GFC, and a consideration of the link between these constraints and general collapse depicted in the LTG. This paper does not attempt to deal with the critical but vexed issue of appropriate governance; other research is shedding light on uploads/Geographie/ globalcollapse-imminent.pdf