Superstorm Sandy is merely the most recent high-impact weather event to raise concerns about extreme weather events becoming more frequent or more severe. Previous examples include the western European heatwave of 2003, the Russian heatwave and the Pakistan floods of 2010, and the Texas heatwave of 2011. However, it remains an open question to what extent such events may be “attributed” to human influences such as increasing greenhouse gases. One way to answer this question is to run climate models under two scenarios, one including all the anthropogenic forcing factors (in particular, greenhouse gases) while the other is run only including the natural forcings (e.g. solar fluctuations) or control runs with no forcings at all. Based on the climate model runs, probabilities of the extreme event of interest may be computed under both scenarios, followed by the risk ratio or the “fraction of attributable risk”, which has become popular in the climatology community as a measure of the human influence on extreme events. This talk will discuss statistical approaches to these quantities, including the use of extreme value theory as a method of quantifying the risk of extreme events, and Bayesian hierarchical models for combining the results of different climate models. This is joint work with Xuan Li (UNC) and Michael Wehner (Lawrence Berkeley Lab). Event flyer.
Systems dynamics and agent-based modeling have recently been used to explore complex systems in a wide range of disciplines. This talk will begin with a quick tutorial outlining the basic principles of these computational tools. Several simulations will be shown to demonstrate the visual aspects of the methods. A few current research applications in public health and medicine at Johns Hopkins will also be described. The talk will conclude with a brief, apolitical analysis of sequestration.
Tak Igusa is the founding Director for Education and Research of the Johns Hopkins Systems Institute. He received an A.B. in Applied Mathematics at Harvard and a Ph.D. in Civil Engineering at Berkeley and was on the faculty at Northwestern University before returning to Baltimore in 1999 as a professor at Johns Hopkins. His research interests are in the application of mathematical modeling to understanding systems in public health, civil infrastructure, and medicine. His interests also include structural dynamics, acoustics, and applications of statistics and probability theory to problems in civil and mechanical engineering, and more recently in atmospheric science.
Tea & Cookies will be served at 2:45 pm
Join the Johns Hopkins Center for Injury Research and Policy for their next Graduate Seminar, featuring Dr. Soames Job of the World Bank. Dr. Job is the Global Lead for Road Safety and he will be discussing the “Safe System Approach for Road Safety” as part of the Engineering Approach to Safety series. This event is being hosted by the Bloomberg School of Public Health and will be held this coming Monday, February 29.
All are welcome to attend!