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