Identification of zones of strong wind events in South Africa

Abstract

This paper summarises the initial stage of development of a wind damage/disaster risk model for South Africa. The aim is to identify the generic zones of various types of strong wind events. The extent of these zones will form the basis for determining the characteristics of typical wind events and subsequently their probabilities of occurrence. No information of this nature is currently available for South Africa. However in the absence of significant seismicity in South Africa, wind forms the most devastating environmental factor affecting the built environment. Several significant wind disasters have occurred including recent events. For example in 1990, 4000 houses were damaged as well as 17 power lines in Welkom. Another example is the Cape Peninsula were 4500 housing units, both formal and informal, were destroyed in 1997. In Umtata in 1998, 18 people died and a lot of houses and buildings were shattered.