System Dynamics Model for Integrated Environmental Assessment of Large Scale Surface Irrigation

Problems of irrigation systems performance and agricultural environment in large scale surface irrigation is analysed with a dynamic simulation model. Present model is a simplified and validated version of an original model built for the analysis of relevant problems in Southeast Turkey. Model consists of components representing farmlands, land and water development, irrigation and salinization, soil nutrients and pest dynamics. In addition, population dynamics and urban development are integrated. Model components include hypothesis on irrigation authorities’ and farmers’ decisions on irrigation release, water consumption, land transformation, crop selection and fertilizer and pesticide application. Structure and behaviour analysis of the model helps understanding the effects of represented decisions on the irrigation system performance and agricultural environment in the long term at regional level. Model structure can further be explored and custom tailored for educational and managerial use in specific case studies

Local climate change assessment at five pilot sites in the Mediterranean region

The objective of this study is to provide an overview of local climate change over the Mediterranean (MED) area under the scope of the InTheMED project, EU funded in the framework of the PRIMA programme. Future precipitation and temperature projections are assessed until the end of this century for five different pilot sites, located in the MED region. To this end, the outputs of 17 Regional Climate Models under the RCP4.5 and RCP8.5 scenarios are used. For each pilot site, the raw climate model data were downscaled at each monitoring station location and bias-corrected on the basis of observations recorded in a 30-year historical period. The changes in the annual precipitation are heterogeneous across the five pilot sites: a negligible variation is expected for some areas and a decrease of up to 30% for others. On the contrary, a significant increase in temperature is expected for all sites, confirming the ongoing warming in the MED region

Bringing the Nature Futures Framework to life: creating a set of illustrative narratives of nature futures

To halt further destruction of the biosphere, most people and societies around the globe need to transform their relationships with nature. The internationally agreed vision under the Convention of Biological Diversity—Living in harmony with nature—is that “By 2050, biodiversity is valued, conserved, restored and wisely used, maintaining ecosystem services, sustaining a healthy planet and delivering benefts essential for all people”. In this context, there are a variety of debates between alternative perspectives on how to achieve this vision. Yet, scenarios and models that are able to explore these debates in the context of “living in harmony with nature” have not been widely developed. To address this gap, the Nature Futures Framework has been developed to catalyse the development of new scenarios and models that embrace a plurality of perspectives on desirable futures for nature and people. In this paper, members of the IPBES task force on scenarios and models provide an example of how the Nature Futures Framework can be implemented for the development of illustrative narratives representing a diversity of desirable nature futures: information that can be used to assess and develop scenarios and models whilst acknowledging the underpinning value perspectives on nature. Here, the term illustrative refects the multiple ways in which desired nature futures can be captured by these narratives. In addition, to explore the interdependence between narratives, and therefore their potential to be translated into scenarios and models, the six narratives developed here were assessed around three areas of the transformative change debate, specifcally, (1) land sparing vs. land sharing, (2) Half Earth vs. Whole Earth conservation, and (3) green growth vs. post-growth economic development. The paper concludes with an assessment of how the Nature Futures Framework could be used to assist in developing and articulating transformative pathways towards desirable nature futures

System Dynamics Model for Integrated Environmental Assessment of Large Scale Surface Irrigation

Problems of irrigation systems performance and agricultural environment in large scale surface irrigation is analysed with a dynamic simulation model. Present model is a simplified and validated version of an original model built for the analysis of relevant problems in Southeast Turkey. Model consists of components representing farmlands, land and water development, irrigation and salinization, soil nutrients and pest dynamics. In addition, population dynamics and urban development are integrated. Model components include hypothesis on irrigation authorities’ and farmers’ decisions on irrigation release, water consumption, land transformation, crop selection and fertilizer and pesticide application. Structure and behaviour analysis of the model helps understanding the effects of represented decisions on the irrigation system performance and agricultural environment in the long term at regional level. Model structure can further be explored and custom tailored for educational and managerial use in specific case studies

Misperceptions of Global Climate Change: Information Policies

Global climate change is an atmospheric commons problem where the basic actors arethe states. In democratic nations national policy initiatives depend on the opinion of theelectorate. Unless there is a proper popular perception of climate change, it will bedifficult to undertake appropriate and timely measures. Previous experimental studiesof people’s understanding of climate change and of other renewable resource problemshave revealed that people misperceive the basic dynamics and that they favourdecisions that are systematically biased in the direction of over-utilisation. In thepresent laboratory experiment, with 251 students, the focus is on understanding whypeople misperceive and how misperceptions could be avoided. Using a simulator, thesubjects are asked to control total global emissions of CO2 to reach a given target forthe atmospheric CO2-concentration. Compared to a previous study we find that fullinformation about a simplified system leads to improved performance, particularlyamong students with a background in mathematics. Subjects perform better in ananalogous, however more easily visualisable system, indicating that they havedifficulties forming appropriate mental models of the more abstract atmosphericproblem. Two information treatments, thought to improve mental models, turn out tohave insignificant effects. Finally, information feedback about the development of theCO2-concentration helps. According to our findings, current information from the IPCCand the standard media coverage is not effective in helping people to choose policiesthat are consistent with their own preferences

Dynamic Simulation Model of Common Pool Resource Cooperation Experiments

We investigate the decision rules adopted by individuals in local communities, whoselivelihoods depend on common pool resource stocks and who face the cooperationdilemma in their everyday life. For this purpose, field experiments are modeled and themodel structure and output are confronted with experimental data and with the relevanttheory of collective action proposed by Ostrom (1998). The field experiments analyzethe cooperative action among coastal communities in Providence Island (ColombianCaribbean Sea). The simulation model is built according to the principles and methodsof System Dynamics. The model formalizes the feedback causality among reputation,trust and reciprocity as suggested by Ostrom (1998). Moreover, based on the payoffstructure used in the experiments, it considers other behavioral factors such astemptation to free ride, profit maximization, and awareness of the individuals infeedback perspective. Depending on the initial conditions and parameter values, modelbehavior replicates major patterns of the experimental data. It reveals path dependentcharacteristic to the initial trust of the individuals in the group. The variables anddecision rules built into the model structure provide the basis for a dialogue between thetheories of collective action and future experimental designs to test and improve suchtheories

Model simplification and validation: Illustration with indirect structure validity tests

Simplification of a large system dynamics model and validation of the simplified version is illustrated. The original model represents agricultural and environmental problems of irrigation development in Southeast Turkey and consists of 62 stock variables. Its simplified version with a narrow model boundary and higher level of aggregation is a general representation of its selected dynamics and consists of 11 stock variables only. Analysis of reference behaviours, indirect structure validity tests and scenario runs reveal simplified model as a valid and useful version of the original. Simplification helps distilling essential model structures that cause selected problems and increases the quality and understanding of models. It can also be a step towards building theory-like structures and general representation of case specific problems in various application domains

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Küresel iklim değişimi; ısı dalgaları, tayfunlar veya kuraklık gibi aşırı iklim olayları yaşandıkça kendisinden söz etmeyi alışkanlık haline getirdiğimiz bir çevre problemiydi

Türkiye - Rusya Nükleer Güç Santrali Anlaşması

Hükümetin 13 Mayıs 2010 tarihinde Rusya ile yaptığı, içinde Mersin, Akkuyu’da 4800 MW kurulu gücünde bir nükleer güç santrali kurulmasını da içeren uluslararası anlaşma, Türkiye’nin enerji politikalarıyla ilgili önemli soru işaretlerini yeniden gündeme getirdi. Birkaç gün ertesinde enerji bakanı Taner Yıldız tarafından yapılan açıklamalar anlaşmanın yalnızca Akkuyu ile sınırlı kalmayacağını, toplamda 10.000 MW nükleer kurulu güce erişecek şekilde ileride Sinop’u da içerebileceğini gösteriyor