Global Security - The Threats are Changing

Humanity's influence upon the environment is growing to encompass the globe and to extend in time to decades and even centuries. One particular global environmental problem, i.e., climatic change, could eventually lead to shifts in agricultural and forestry growing zones, changes in freshwater supply and a rise in sea level, and eventually to migration and "environmental refugees". This could further result in civil unrest, political instability, militarism, and terrorism which could pose as large a threat to world security as the ideological struggle from which we appear to be emerging. The trace gases leading to climatic change, especially carbon dioxide and methane, are closely linked with the production of energy. A more efficient use of energy, both in the developed and developing world, should be the first and main strategy for attacking the impending global threat of climatic change. Incentives for increasing energy efficiency in the developed world should be through the imposition of resource taxes such as carbon taxes. In the developing world, energy efficiency and development could advance hand in hand, if the proper infrastructure were created. This could be financed at least partially by the resource taxes collected in the developed world

IIASA's Work on Climate Change: Assessing Environmental Impacts

This Status Report is adapted from a lecture presented by Matthias Jonas at the Institute for Meteorology and Geophysics, University of Vienna, May 1992. In his lecture, Dr. Jonas clearly summarizes the status of the work being carried out within the Climate Change Projections Study at IIASA. This work involves linking a policy-oriented climate change model, the Integrated Model to Assess the Greenhouse Effect (IMAGE), to models of ecological change such as the Global Vegetation Model, the Timber Assessment Model, and the Regional Acidification INformation and Simulation (RAINS) model. These models were at least partially developed at IIASA. The result of this linkage work, which is being carried out in collaboration with the Netherlands National Institute of Public Health and Environmental Protection (RIVM), and possibly other institutes, is intended to be a tool to help policy makers assess in a rapid and time-dependent way changes in regional ecology resulting from various greenhouse gas emission scenarios

Estimation of GCM Temperature Trends for Different Emission Scenarios with the help of the Integrated Model to Assess the Greenhouse Effect (IMAGE)

How useful are General Circulation Models (GCMs) for policy makers? Of course, they are considered to be the most powerful models that are presently available for predicting future climates and for carrying out research. Their disadvantage is that they are very time-consuming and very expensive to run for any greenhouse gas emission or concentration scenario. For that reason, GCMs have been run only for a small number of scenarios. However, policy makers are interested in being able to analyze a large number of scenarios. The Integrated Model to Assess the Greenhouse Effect (IMAGE) developed by the National Institute for Public Health and Environmental Protection (RIVM) in the Netherlands is a scientifically based, policy oriented model that can calculate the effect of different greenhouse gas emissions on global surface air temperature and sea level rise. The major advantage of IMAGE is its quick turnaround time. Its disadvantage is that it gives only global values of surface temperature and sea level rise, which have insufficient spatial resolution to estimate ecological impacts on a regional basis. We propose a methodology for combining the fast turnaround time and time-dependent surface temperature results of IMAGE with the spatial resolution of GCMs to provide a linkage between IMAGE and models of ecological change that could provide policy-makers with valuable information about the consequences of different levels of reduction of greenhouse gas emissions

Molecular beam epitaxy of highly mismatched N-rich GaNSb and InNAs alloys

GaN materials alloyed with group V anions form the so-called highly mismatched alloys (HMAs). Recently, the authors succeeded in growing N-rich GaNAs and GaNBi alloys over a large composition range by plasma-assisted molecular beam epitaxy (PA-MBE). Here, they present first results on PA-MBE growth and properties of N-rich GaNSb and InNAs alloys and compare these with GaNAs and GaNBi alloys. The enhanced incorporation of As and Sb was achieved by growing the layers at extremely low growth temperatures. Although layers become amorphous for high As, Sb, and Bi content, optical absorption measurements show a progressive shift of the optical absorption edge to lower energy. The large band gap range and controllable conduction and valence band positions of these HMAs make them promising materials for efficient solar energy conversion devices

Sustainable Development: A Systems Approach

This Status Report summarizes the final report of the IIASA Environment and Development Study which was submitted to the Secretariat of the United Nations Conference on Environment and Development (UNCED) in December 1991. As a systems analysis institute, IIASA was asked by UNCED in mid-1990 to explore the usefulness of systems analysis in: identifying some of the important linkages among population, environment, and development; examining some of the underlying causes of environmentally unsustainable development; and in formulating and implementing policies for more sustainable development. The work first involved the formulation of conceptual models of the socio-ecological system in which we live. The application of systems analysis to environment and development was then examined in several case studies. The case studies, based mainly upon past and present work carried out here at IIASA, indicated that systems analysis is potentially very useful in helping us towards a sustainable future. However, the work that is described in the report gives only a few examples of what could be done in the years following UNCED

CMAS challenges to CMC-T/EBC systems

Gas turbine technology is undergoing a major transition with the recent implementation of SiC based ceramic composites (CMCs) in aircraft engines. While the potential improvement in temperature capability (≥1500°C) is unprecedented, there are a number of issues that limit the full exploitation of such potential. In addition to the longstanding concern for low temperature oxidative embrittlement and the limited temperature capability of current bond coats and matrices, the susceptibility of the protective SiO2 to volatilization in the combustion environment requires the use of environmental barrier coatings (EBCs) to achieve durability targets. Most EBC concepts, however, are based on silicates and are thus susceptible to degradation by molten silicate deposits generically known as CMAS originating from mineral debris ingested into engines with the intake air. This presentation will discuss the thermodynamic and mechanistic foundation of the degradation of EBCs by CMAS, recent progress in establishing the relevant phase equilibria for these systems, and the role of the CMAS composition on the extent of degradation, as well as perspective on mitigation. (Research supported by ONR, AFOSR and the P&W Center of Excellence in Composites at UCSB.

L'environnement futur en Europe de l'ést et de l'ouest: Consequences de divers scénarios de développement

This study analyzes eleven European environmental policy "dilemmas" for four alternative socioeconomic development pathways to the year 2030. The dilemmas include problems associated with: water management, soil acidification, forestry wood supply, marginalized land, sea level rise, coastal problems, chemical "time bombs", non-point source toxic materials, transport growth, urbanization, and summer oxidant episodes

Future Environments for Europe: Some Implications of Alternative Development Paths

This study analyzes eleven European environmental policy "dilemmas" for four alternative socioeconomic development pathways to the year 2030. The dilemmas include problems associated with: water management, soil acidification, forestry wood supply, marginalized land, sea level rise, coastal problems, chemical "time bombs", non-point source toxic materials, transport growth, urbanization, and summer oxidant episodes

Women, anger, and aggression an interpretative phenomenological analysis

This study reports a qualitative phenomenological investigation of anger and anger-related aggression in the context of the lives of individual women. Semistructured interviews with five women are analyzed using interpretative phenomenological analysis. This inductive approach aims to capture the richness and complexity of the lived experience of emotional life. In particular, it draws attention to the context-dependent and relational dimension of angry feelings and aggressive behavior. Three analytic themes are presented here: the subjective experience of anger, which includes the perceptual confusion and bodily change felt by the women when angry, crying, and the presence of multiple emotions; the forms and contexts of aggression, paying particular attention to the range of aggressive strategies used; and anger as moral judgment, in particular perceptions of injustice and unfairness. The authors conclude by examining the analytic observations in light of phenomenological thinking