Bi-Hazard Assessment for Timely and Effective Disaster Management: Free State Disaster Area 2015

Abstract

conjure up. With its slow-on-set creeping nature, at its most severe levels it can last longer and extent across large areas generating secondary hazards such as dust bowls, land degradation, destruction of terrestrial and aquatic wildlife habitats and widespread wildfires. Therefore thereis no universal definition of drought, therefore “Operational definitions can also be used to analyze drought frequency, severity, and duration for a given historical period. Such definitions, however, require weather data on hourly, daily, monthly, or other time scales and, possibly, impact data (e.g., crop yield), depending on the nature of the definition being applied. Developing climatology of drought for a region provides a greater understanding of its characteristics and the probability of recurrence at various levels of severity. Information of this type is extremely beneficial in the development of response and mitigation strategies and preparedness plans”. Following the declaration of the Free State province on the 10th September 2015 being drought disaster area, the current study aims to assess drought and fire hazards from regional operational indices in order to help disaster managers and political authorities facilitate resource allocation mobilization in response to the present situation. The study collected January 2014 to October 2015 precipitation, wind speed, temperature, and relative humidity data from a web-based source. A modified water balance method in conjunction with the works of Iyengar and Sudashan were used in constructing a composite drought index. This analysis which was conducted in three dimensions, severity, frequency and spatial extent, revealed the Free State province generally experiencing the same magnitude of frequencies and severity, although, rankings of spatial extent show a descending trend from the northern to the northeastern parts of the province and lastly the southern parts. The same spatial extent was revealed by a Swedish Angstrom index for fire dangers.