Satellite Monitoring of Floods as a Part of the Early Warning System

Abstract

Floods are short-term, unexpected and frequently unpredictable. Floods are not just local phenomenon but can happen everywhere. Coincidence plays an important role in the size and frequency of flood formation. High floods are usually a result of a combination of several factors, and call for the theory of catastrophes to come into effect. All this complicates forecasting and increases the risk factor. Numerous attempts to use satellite surveys for mapping of inundation have not brought about sufficient reliable material for an estimation of the danger of occurrence and the development of floods. The reason for this lies in features of investigated process and used information, which should be used in an optimum combination. In Russia there we have twenty years of experience in the thematic analysis of satellite images; and have developed a technique for the estimation of river flood-plain submersion. The operative satellite information on the average resolution, aerial and satellite photographs are used. The reference data (volume of water and inundated area at any water stage) on zones of flood-plains of the Ob and Volga rivers are prepared. The typical layouts of flooding are revealed.