Paleoclimate Extremes in Proxy Data

• Activity Number: 290
• Type: Topic Contributed
• Date/Time: Tuesday, August 3, 2010 : 8:30 AM to 10:20 AM
• Sponsor: Section on Statistics and the Environment
• Author(s): Elizabeth C. Mannshardt-Shamseldin*+
• Companies: Statistical and Applied Mathematical Sciences Institute
• Keywords: Extreme ; Proxy Data ; Reconstruction ; climate change

Abstract

There is often interest in determining which year in a proxy reconstruction was warmest, coldest, or otherwise extreme. For example, using proxy data to address questions such as "Were the 1990s the warmest decade of the last millennium?", "Is there evidence that the extreme events of recent decades are more extreme than previous decades?" The methodology of extreme value theory has not been widely applied to this problem. What can the statistics of extremes offer? Are there temporal trends among the extreme temperature values in proxy data? There is also interest in determining how these reconstructions compare to the observed climate. This leads to possible calibration with climate model output, with models run under different greenhouse gas assumptions. How do the probabilities of extreme events compare for proxy reconstruction events and current observed extreme events?