ABSTRACT
Drought is one of the world’s costliest natural hazards characterized by a significant decrease of water availability during a prolonged period of time over a large area. Thus, drought management has become an important issue in the drought-prone parts of Ethiopia in order to reduce the adverse impacts of drought hazards and potential disasters through drought prevention and mitigation measures as well as preparedness. Drought assessment often employs the measure of the shortfall of the hydro-meteorological parameters such as rainfall, streamflow, soil moisture etc. from the long-term average value. Drought monitoring includes the wide application of the drought indices that measure the deficit of hydrologic cycle components as compared to the long-term mean. A number of researchers have suggested that instead of developing a new single drought indicator, it is worthwhile to combine the existing drought indices into a comprehensive and integrative drought index. The chapter also presents an overview of the key concepts discussed in this book.
