Seite - 7 - in options, Band summer 2016

research news 7summer 2016 + optionswww.iiasa.ac.at iiasa research Probing paradoxes in people’s behavior Game theory has evolved into a powerful tool for behavioral study of humans, communities, and animals. But when IIASA researcher Dan Jessie observed actual behavior sometimes failing to match game theory predictions he was driven to ask “what’s going on?” “We see humans are much more complicated than the models are ever going to be and so you see a lot of paradoxes where the model predicted something— but for some reason the subject did something completely unexpected,” says Jessie. This unexpected behavior is most often seen when players cooperate even though the model predicts they will pursue their own interest. “For example, in a prisoners dilemma game where each player always has an incentive to go after their own selfish pay‑off—but doing so leads to a mutually inferior outcome —you would see people  cooperating.” Jessie and coauthor Ryan Kendall at the University of Southern California conducted experiments which address this issue and have submitted a paper for publication describing the results. “You have these different models arguing about which one is better and now we can say, well look, we can describe mathematically where they work and where they don’t.” Critical to their analysis is a new way to decompose games, developed in collaboration with Donald Saari of the University of California Irvine, into the portion that encourages individuals to seek “personally preferred payoffs” and the portion that requires cooperation among players. As Jessie says, “we have a way of comparing models now that wasn’t around before.” KS Further info Jessie  DT, Saari  DG (2015). Strategic and behavioral decomposition of games. IIASA Interim Report IR-15-001. Daniel Jessie jessie@iiasa.ac.at Electricity production vulnerable to climate and water change Climate change impacts and associated changes in water resources could lead to reductions in electricity production capacity for more than 60% of the hydropower and thermoelectric power plants worldwide from 2040–2069, according to a new study. Yet adaptation measures focused on efficiency and flexibility could mitigate much of the decline. “Hydropower plants and thermoelectric power plants—which are nuclear, fossil‑, and biomass‑fueled plants converting heat to electricity—both depend on water availability” explains IIASA researcher Michelle van Vliet, who led the study. “In  addition, water temperature plays a critical role for cooling in thermoelectric power generation.” Together, hydropower and thermoelectric power currently contribute to 98% of electricity production worldwide. Model projections show that climate change will impact water resource availability and increase water temperatures in many regions. A  previous study by the researchers showed that these changes could result in significant reductions in thermoelectric power supply in Europe and the US. This new study expands the research to a global level, using data from 24,515 hydropower and 1,427 thermoelectric power plants. In addition, they tested six adaptation options to mitigate the vulnerability to changes in climate and water  resources. “This is the first study of its kind to examine the linkages between climate change, water resources, and electricity production on a global scale. We clearly show that power plants are not only causing climate change, but they might also be affected in major ways by climate,” says  IIASA Energy Program Director Keywan Riahi, a study coauthor. KL Further info Van  Vliet  MTH, Wiberg  D, Leduc  S, Riahi  K (2016). Power-generation system vulnerability and adaptation to changes in climate and water resources. Nature Climate Change 6(4):375–380 [doi:10.1038/ NCLIMATE2903]. Michelle van Vliet vanvliet@iiasa.ac.at