Natural hazards in South America: In search of a method and a theory

Traditional natural hazard researchers have failed to deal with hazard occurrences in Latin America in a comprehensive and coherent fashion because of their cultural bias and lack of knowledge about the regional implications of hazard conditions.The attempt is made in this paper to point out that some of the climatic hazards that beset South America, such as El Nino phenomenon on the coasts of Peru and Chile, the frosts in south-central Brazil, and the droughts of NE Brazil, are not isolated occurrences, but meteorological anomalies whose implications encompass not only the affected areas but also distant environments and economies.Systems analysis is utilized to prove that the oceanic-climatic El Nino phenomenon is genetically linked to global climatic anomalies and that the effects of such anomalies are felt in the ecological balance of the Pacific basin, of Africa, and of S Asia. Among their economic implications are shortages of anomal protein (from fish meal) and crop failures in Africa and the Soviet Union. Political consequences of hazardous conditions are also evident at hand of the 1971–73 climatic oscillations, of which El Nino was a symptom.In order to provide natural hazard research with a coherent theory, the cusp catastrophe theory of Thom and Zeeman is applied to the understanding of the conditions that lead to the onset of an oceanic-climatic El Nino occurrence. It is suggested that — considering that such a situation arises from interdependent ocean-atmosphere feedbacks — only under very special circumstances does this interplay lead to the sudden development of an El Nino condition. Catastrophe theory is not a deterministic theory but it considers the possibility of sudden change of states within a system.