CHANGE OF SCALING BEFORE EXTREME EVENTS IN COMPLEX SYSTEMS

Critical transitions. Natural and human-made complex systems persistently generate critical transitions – rare extreme events, also known as disasters, crises etc. Predictive understanding of critical transitions is commonly regarded as one of the major unsolved problems of basic science. The dramatic practical aspect of that problem is disaster preparedness. Global population, economy, and environment become increasingly vulnerable to a throng of disasters, already threatening the very survival and sustainability of our civilization (Science for Survival and Sustainable Development, 2000; G8-UNESCO World Forum on ‘Education, Innovation and Research: New Partnership for Sustainable Development’, 2007). This study explores a specific observable phenomenon, preceding critical transitions. It is a change of scaling – the size distribution of events comprising a process considered. Scaling itself is a staple of studying complexity. However premonitory change of scaling has been found so far only in seismicity and in other forms of multiple fracturing, with major failures (e.g.