Madison Chaos and Complex Systems Seminar

Spring 2011 Seminars

All seminars are Tuesday at 12:05 pm in 4274 Chamberlin except as noted.

Short List

Jan 18, 2011 - Mike Koenigs, Psychiatry
Jan 25, 2011 -
Feb 1, 2011 - Jean Bahr, Geoscience
Feb 8, 2011 - Rich Halverson, Education
Feb 15, 2011 -
Feb 22, 2011 - Vladimir Zhdankin, Physics
Mar 1, 2011 -
Mar 8, 2011 - Bruce Wampold, Counseling Psychology
Mar 15, 2011 - NO SEMINAR (spring break)
Mar 22, 2011 -
Mar 29, 2011 - Ned Sibert, Chemistry
Apr 5, 2011 - Anastasios Tsonis, UW-Miwaukee
Apr 12, 2011 - Andy Sheinis, Mathematics
Apr 19, 2011 -
Apr 26, 2011 -
May 3, 2011 -

Join us for lunch during the summer on the Union Terrace at noon each Tuesday, starting May 10th!

Abstracts

April 5, 2011

A new dynamical mechanism for major climate shifts

Anastasios Tsonis, Department of Mathematical Sciences, UW-Milwaukee

We construct a network of observed climate indices in the period 1900–2000 and investigate their collective behavior. The results indicate that this network synchronized several times in this period. We find that in those cases where the synchronous state was followed by a steady increase in the coupling strength between the indices, the synchronous state was destroyed, after which a new climate state emerged. These shifts are associated with significant changes in global temperature trend and in ENSO variability. The latest such event is known as the great climate shift of the 1970s. We also find the evidence for such type of behavior in three climate simulations using a state-of-the-art model. This is the first time that this mechanism, which appears consistent with the theory of synchronized chaos, is discovered in a physical system of the size and complexity of the climate system.