Self-Organized Criticality (SOC)
Self-organized criticality (SOC) has become a popular concept in several fields of science since the late 1980s. It provides a framework for describing systems approaching quasi-steady states exposed to fluctuations of all sizes following power-law distributions. The main applications have focused on natural hazards on Earth and on extraterrestrial processes. SOC has also been proposed as a concept for explaining variations in climate in some studies, although its applicability is less clear here. In general there is considerable confusion in the literature about the concept, in particular about the term “criticality" being an essential part of the SOC concept. The class will focus on the basics behind the concept, the most widespread applications, and potential applications from the participants' fields of research.
References
Aschwanden, M., Crosby, N., Dimitropouly, M., Georgoulis, M., Hergarten, S., McAteer, J., Milovanovi, A., Mineshige, S., Morales, L., Nishizuka, N., Pruessner, G., Sanchez, R., Sharma, A., Strugarek, A., and Uritsky, V.: 25 years of self-organized criticality: solar and astrophysics, Space Sci. Rev., pp. 1-120, doi:10.1007/s11214-014-0054-6, 2014.
Bak, P.: How Nature Works – the Science of Self-Organized Criticality, Copernicus, Springer, Berlin, Heidelberg, New York, 1996.
Hergarten, S.: Self-Organized Criticality in Earth Systems, Springer, Berlin, Heidelberg, New York, 2002.
Jensen, H. J.: Self-Organized Criticality – Emergent Complex Behaviour in Physical and Biological Systems, Cambridge University Press, Cambridge, New York, Melbourne, 1998.
Stefan Hergarten studied physics and mathematics at Bonn University and finished his PhD in geophysics in 1996. From 2005 to 2010 he was professor for Computational Earth Sciences at the University of Graz, and from 2011 to 2012 at Graz University of Technology. Since 2012 he is interim professor for Near-Surface Geophysics af the University of Freiburg. Self-organized criticality with focus on natural hazards, in particular earthquakes, mass movements, and wildfires, has been one of his major scientific fields since his PhD. Tectonic geomorphology, hydrogeologic modeling, and impact processes are further fields of his research.
