It's The End Of The World As We Know It (Update)

A Minimal Model for Human and Nature Interaction, 2012, (PDF) as submitted.

Keith's 20 March update: (The University of Maryland has pulled this 2012 paper offline - summary/excerpts below). This is apparently the newer 2014 paper - submitted on 18 March - on the same topic - with a nearly identical summary: "Human and Nature Dynamics (HANDY): Modeling Inequality and Use of Resources in the Collapse or Sustainability of Societies".

Excerpts from both versions of the paper are included below - after the link.

NASA Statement on Sustainability Study

"A soon-to-be published research paper 'Human and Nature Dynamics (HANDY): Modeling Inequality and Use of Resources in the Collapse or Sustainability of Societies' by University of Maryland researchers Safa Motesharrei and Eugenia Kalnay, and University of Minnesota's Jorge Rivas was not solicited, directed or reviewed by NASA. It is an independent study by the university researchers utilizing research tools developed for a separate NASA activity. "As is the case with all independent research, the views and conclusions in the paper are those of the authors alone. NASA does not endorse the paper or its conclusions."

Keith's 20 March update: The paper claims that it was partially funded by NASA - and mentions a specific NASA grant i.e. "NASA/GSFC grant NNX12AD03A". NASA seems to be saying that it was not funded by NASA.

Keith's 21 March update: NASA responded to my questions on this topic:

NASAWATCH: Did NASA money support this work and if so how much and who (program, project, directorate) paid for it?

NASA: In 2010, NASA funded a small pilot project at the University of Maryland to adapt a physical climate simulation model for use at the University. A small secondary task, valued at less than $30,000, was used to couple the climate model with a population model. The resulting model, the "Human And Nature DYnamical' (HANDY) model is a simplified model of human-climate interactions.

NASAWATCH: If NASA funds were used why has it been pulled offline? Is not such work a matter of public record?

NASA: NASA has not pulled the paper offline or directed it to be done. Questions regarding the paper itself should be directed to the University of Maryland.

NASAWATCH: Did NASA solicit this research - and if so what specific program solicited and funded it?

NASA: NASA did not solicit the research in this paper. The HANDY model was part of a pilot study funded as part of Goddard's Modeling, Analysis and Prediction program.

NASAWATCH: Is there a statement of work/proposal to accompany this paper?

NASA: Yes. There was a Statement of Work that covered the development of the model.

NASAWATCH: Does NASA endorse the findings?

NASA: No.

NASAWATCH: Will NASA be publishing/promoting this paper and its findings?

NASA: No.

"Human and Nature Dynamics (HANDY): Modeling Inequality and Use of Resources in the Collapse or Sustainability of Societies", 2014 (newer paper)

Safa Motesharrei
School of Public Policy and Department of Mathematics
University of Maryland and National Socio-Environmental Synthesis Center (SESYNC)

Jorge Rivas
Department of Political Science University of Minnesota and Institute of Global Environment and Society (IGES)

Eugenia Kalnay
Department of Atmospheric and Oceanic Sciences University of Maryland

March 18, 2014

Abstract There are widespread concerns that current trends in resource-use are unsustainable, but possibilities of overshoot/collapse remain controversial. Collapses have occurred frequently in history, often followed by centuries of economic, intellectual, and population decline. Many different natural and social phenomena have been invoked to explain specific collapses, but a general explanation remains elusive. In this paper, we build a human population dynamics model by adding accumulated wealth and economic inequality to a predator-prey model of humans and nature. The model structure, and simulated scenarios that offer significant implications, are explained. Four equations describe the evolution of Elites, Commoners, Nature, and Wealth. The model shows Economic Stratification or Ecological Strain can independently lead to collapse, in agreement with the historical record. The measure "Carrying Capacity" is developed and its estimation is shown to be a practi- cal means for early detection of a collapse. Mechanisms leading to two types of collapses are discussed. The new dynamics of this model can also reproduce the irreversible collapses found in history. Collapse can be avoided, and population can reach a steady state at maximum carrying capacity if the rate of depletion of nature is reduced to a sustainable level and if resources are distributed equitably.

---

In sum, the results of our experiments, discussed in section 6, indicate that either one of the two features apparent in historical societal collapses -- over-exploitation of natural resources and strong economic stratification -- can independently result in a complete collapse. Given economic stratification, collapse is very difficult to avoid and requires major policy changes, including major reductions in inequality and population growth rates. Even in the absence of economic stratifica- tion, collapse can still occur if depletion per capita is too high. However, 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.

In the upcoming generations of HANDY, we plan to develop several extensions including: (1) disaggregation of Nature into nonrenewable stocks, regenerating stocks, and renewable flows, as well as the introduction of an investment mechanism in accessibility of natural resources, in order to study the effects of investment in technology on resource choice and production efficiency; (2) making inequality (κ) endogenous to the model structure; (3) introduction of "policies" that can modify parameters such as depletion, the coefficient of inequality, and the birth rate; and, (4) introduction of multiple coupled regions to represent countries with different policies, trade of carrying capacity, and resource wars.

Those interested in obtaining the model code can contact the authors.

Acknowledgements

We are grateful to Profs. Matthias Ruth, Victor Yakovenko, Herman Daly, Takemasa Miyoshi, Jim Carton, Fernando Miralles-Wilhelm, Ning Zeng, and Drs. Robert Cahalan and Steve Penny for many useful discussions. Study of the "Equitable Society" scenarios (i.e., with Workers and Non- Workers), the scenario presented in section 5.2.5, in particular, was suggested by V. Yakovenko. We would also like to thank anonymous reviewer No. 1 for having highlighted to us the importance of the capability of HANDY to naturally produce irreversible collapses, which is not found in earlier models. We would especially like to thank the editors of this journal for alerting us to the model and work done by Brander and Taylor, of which we were unaware, and allowing us to revise our article to account for this new information.

This work was partially funded through NASA/GSFC grant NNX12AD03A.


A Minimal Model for Human and Nature Interaction, 2012, (PDF) as submitted (Now deleted)

A Minimal Model for Human and Nature Interaction

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

November 13, 2012

Abstract

There are widespread concerns that current trends in population and resource-use are unsustainable, but the possibilities of an overshoot and collapse remain unclear and contro- versial. Collapses have occurred frequently in the past ve thousand years, and are often followed by centuries of economic, intellectual, and population decline. Many di erent nat- ural and social phenomena have been invoked to explain speci c collapses, but a general explanation remains elusive. Two important features seem to appear across societies that have collapsed: (1) Ecological Strain and (2) Economic Strati cation. In this paper, the structure of a new model and several simulated scenarios that o er signi cant implications are explained. The model has just four equations that describe the evolution of the populations of Elites and Commoners, Nature, and accumulated Wealth. Mechanisms leading to collapse are discussed and the measure \Carrying Capacity" is devel- oped and de ned. The model suggests that the estimation of Carrying Capacity is a practical means for early detection of a collapse. Collapse can be avoided, and population can reach a steady state at the maximum carrying capacity, if the rate of depletion of nature is reduced to a sustainable level, and if resources are distributed equitab

----

In sum, results of our experiments, discussed in section 6, indicate that either one of the two features apparent in historical societal collapses -- over-exploitation of natural resources and strong economic strati cation -- can independently result in a complete collapse. Given economic strati cation, collapse is very dicult to avoid and requires major policy changes, including major reductions in inequality and population growth rates. Even in the absence of economic strati cation, collapse can still occur if depletion per capita is too high. However, 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. This version of HANDY so far contains only one region, and only renewable natural resources. In the next version, we plan to include several extensions including:

- Disaggregation of Nature into nonrenewable stocks, renewable stocks, and ows.

- The introduction of "government policies" that can modify parameters such as depletion, the coecient of inequality and birth rate, to see whether it is possible to avoid a collapse when the carrying capacity is exceeded.

- The introduction of multiple coupled regions to represent countries with di erent policies, trade carrying capacity and resource wars.

We have posted HANDY on http://www.atmos.umd.edu/~ekalnay/handy-ver1.mdl We welcome our readers to download the code, perform other experiments, and post their results at the same webpage.

Acknowledgements

We are grateful to Profs. Matthias Ruth, Victor Yakovenko, Herman Daly, Takemasa Miyoshi, Jim Carton, Fernando Miralles-Wilhelm, Ning Zeng, Drs. Robert Cahalan and Steve Penny, and Ms. Erin Lynch for many useful discussions. Study of the "Equitable Society" scenarios (i.e., with Workers and Non-Workers), in particular, the scenario presented in section 5.2.5, was suggested by V. Yakovenko. This work was partially funded through NASA/GSFC grant NNX12AD03A, known as "Collaborative Earth System Science Research Between NASA/GSFC and UMCP".

NASA-Backed Study Says Humanity Is Pretty Much Screwed, Gizmodo

"Hope you've enjoyed civilized life, folks. Because a new study sponsored by NASA's Goddard Space Flight Center says the world's industrial societies are poised to collapse under the weight of their own unsustainable appetites for resources. There goes the weekend . . . and everything after it for the rest of our lives."

Keith's 17 March note: I have asked NASA PAO for a copy of this report.

Keith's 18 March update: It is rather baffling in the 21st Century for NASA to be funding research on the future of civilization that does not include extraterrestrial resources as part of the equation - at the same time that the agency wants to go grab an asteroid. The authors have their heads in the sand as they totally ignore the fact that Earth sits amidst vast resources outside of its biosphere. This is rehashed 1960s Club of Rome defeatist thinking all over again. I wonder how much money NASA wasted on this. I'll ask.

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This page contains a single entry by Keith Cowing published on March 20, 2014 6:18 PM.

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