Search Results
Agents, Bayes, and Climatic Risks - a modular modelling approach
2005, Haas, A., Jaeger, C.
When insurance firms, energy companies, governments, NGOs, and other agents strive to manage climatic risks, it is by no way clear what the aggregate outcome should and will be. As a framework for investigating this subject, we present the LAGOM model family. It is based on modules depicting learning social agents. For managing climate risks, our agents use second order probabilities and update them by means of a Bayesian mechanism while differing in priors and risk aversion. The interactions between these modules and the aggregate outcomes of their actions are implemented using further modules. The software system is implemented as a series of parallel processes using the CIAMn approach. It is possible to couple modules irrespective of the language they are written in, the operating system under which they are run, and the physical location of the machine
Risk, rationality, and resilience
2010, Jaeger, C.
Improving our ability to cope with large risks is one of the key challenges for humankind in this century. This article outlines a research program in this perspective. Starting with a concrete example of a relatively small disaster, it questions simplistic ideas of rationality. It then proposes a fresh look at the concepts of probability and utility in the context of socio-ecological systems. This leads first to an emphasis on the problem of equilibrium selection, and then to a distinction between three kinds of resilience that matter both for theory and practice of risk management. They can be investigated by paying attention to the transitions into and out of actual disasters.
Geoengineering climate by stratospheric sulfur injections: Earth system vulnerability to technological failure
2009, Brovkin, V., Petoukhov, V., Claussen, M., Bauer, E., Archer, D., Jaeger, C.
We use a coupled climate-carbon cycle model of intermediate complexity to investigate scenarios of stratospheric sulfur injections as a measure to compensate for CO2-induced global warming. The baseline scenario includes the burning of 5,000 GtC of fossil fuels. A full compensation of CO2-induced warming requires a load of about 13 MtS in the stratosphere at the peak of atmospheric CO2 concentration. Keeping global warming below 2°C reduces this load to 9 MtS. Compensation of CO 2 forcing by stratospheric aerosols leads to a global reduction in precipitation, warmer winters in the high northern latitudes and cooler summers over northern hemisphere landmasses. The average surface ocean pH decreases by 0.7, reducing the calcifying ability of marine organisms. Because of the millennial persistence of the fossil fuel CO2 in the atmosphere, high levels of stratospheric aerosol loading would have to continue for thousands of years until CO2 was removed from the atmosphere. A termination of stratospheric aerosol loading results in abrupt global warming of up to 5°C within several decades, a vulnerability of the Earth system to technological failure. © 2008 The Author(s).
Avoiding the avoidable: Towards a European heat waves risk governance
2011, Lass, W., Haas, A., Hinkel, J., Jaeger, C.
The death toll of recent heat waves in developed countries has been remarkably high, contradicting the common assumption that high levels of economic and technological development automatically lead to lower vulnerability to weather extremes. Future climate change may further increase this vulnerability. In this article we examine some recent evidence of heat wave-related mortality and we conclude that while economic wealth and technological capacity might be a necessary condition for adequately coping with adverse climate change effects, they are not sufficient. Questions of awareness, preparedness, organizational issues, and actor networks have to be addressed in a proactive and focused manner in order to avoid future heat wave damages. We propose some practical consequences for heat wave adaptation measures by adopting a risk governance framework that can be universally applied, as it is sufficiently flexible to deal with the multi-level and often fragmented reality of existing coping measures.
Stern's Review and Adam's fallacy
2008, Jaeger, C., Schellnhuber, H.J., Brovkin, V.
The Stern Review has played an enormous role in making the world of business aware of the challenge of long-term climate change. In order to make real progress on the basis of this awareness, it is important to pay attention to the difference between human suffering and losses of gross domestic product (GDP). The Review has compared climate change to experiences of suffering like World War I. That war, however, hardly affected global GDP. The long-term damages to be expected from business-as-usual greenhouse gas emissions include loss of the coastal cities of the world over the next millennia. This would be an act of unprecedented barbarism, regardless of whether it would slow down economic growth or perhaps even accelerate it. Business leaders worried about climate change need to pay attention to the tensions between ethical and economic concerns. Otherwise, a credibility crisis threatens global climate policy. An important step to establish the credibility needed for effective climate policy will be to gradually move towards a regime where emission permits are auctioned, not handed out as hidden subsidies. The revenues generated by permit auctions should be used to establish a global system of regional climate funds. © 2008 The Author(s).