Human responses and adjustments to the 1963-65 ashfalls of Irazu Volcano, Costa Rica: a geographical study of environmental perception

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The 1963-65 ashfalls of Irazu Volcano, in the Central Valley of Costa Rica, were chosen for this study of environmental perception of natural hazards, because they presented a test case to be compared with earlier perception studies car ried out by geographers for other natural hazards elsewhere. The writer employed a socio-geographical approach similar to those studies, but sought to expand the substance and methodology of these by emphasizing their spatial interpretation. The first part of the study focuses on the spatial, qualitative and quantitative aspects of the total extent of destruction, disruption, contamination and, to some degree, pollution resulting from the Irazu Volcano ashfalls of 1963-65. This section, involving the recording and mapping of the various disruptive effects and the establishment of the source, range , degree and character of intensity and severity of these effects is presented against the geographical background of the bio sphere, mainly in terms of diverse climatic conditions, highly variable topography, soils of varying fertility, and distinctive land use and human activities. The second part of the study analyses the human perception of the hazard by means of a questionnaire based upon one developed by the Natural Hazard Research Group (Institute of Behavioral Sciences, Boulder, Colorado). This questionnaire brings into focus the extent to which individual perception of volcanic ashfalls coincides with the facts of their distribution and severity. The survey provides data for 170 respondents on socio-economic characteristics and spatial patterns as related to perception. In addition, information is gathered by using a sentence completion test and a list of adjustments. Following cross tabulations and interpretation of the variables, a first analysis of human perception is derived, and perceptivity patterns are outlined on a series of maps. These maps illustrate the dramatic coincidence between the real environment of the volcanic event and this environment as it was perceived by the affected populations. The results of three factor analyses, which were also mapped, supported this conclusion. The principal components demonstrated the locational characteristics of socio-economic values, conceptual coherence in relation to distance from the hazard source and other aspects of location not related to the hazard. These results could be then tied into material on physical and agro-economic regions from the first part of the study. It was concluded that in Costa Rica, education and economic status were the major determinants of human perception, but location in relation to Irazu Volcano, the source of the hazard, was also significant. Besides adding to the geographic knowledge of the Central Valley of Costa Rica, the study hopefully provides a source of hypotheses and methods for future studies on the perception of natural hazards of a different or similar nature.
Bibliography: p. 239-252.
Lemieux, G. H. (1975). Human responses and adjustments to the 1963-65 ashfalls of Irazu Volcano, Costa Rica: a geographical study of environmental perception (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from doi:10.11575/PRISM/20286