摘要：About the polysemantics of the extreme geographical events. The present day concepts referring to the extreme geographical phenomena (such as hazards, risks, disasters, catastrophes etc.) are used into an inconsequent and contradictory manner. It can be noticed first the narrow significance of the term “hazard” which is often connected only with the threshold events that affect human communities, being ignored in this respect the role of the hazard as a law mechanism of evolution in the whole nature. On the other hand, the discrepancy of a purely abstract concept to indicate concrete geographical phenomena and the improper using of “hazard” and “risk” as synonyms are also argued. Therefore we define “hazard” as the necessary and unpredictable cronotop of a causal network of a system able to generate nonlinear energy discharge. By consequence, the hazard is only the source of the extreme geographical phenomena and not the phenomena itself. The assume of the potentiality of a hazard by a collectivity (unconscious, conscious or instinctual) defines the state of “risk”. In this respect, our point of view is that the notion “hazard” is improper to define “risk” or “disaster”, the last one being an effect that occurs after the actualization of risk. In this respect we consider that the term of “extreme geographical phenomena” induce less confusion than “hazard” together with it express an “event”.
