INTRODUCTION - Modelling Uncertainty in Flood Forecasting Systems - page 6

Figure 1.3. Conceptual structure of a flood forecasting, warning and response
system (FFWRS) (source: Parker et al., 1994)
The flood forecasting and flood warning sub-systems are two major components of the
FFWRS, which are discussed further in this thesis. Flood forecasting is the process of
estimating the conditions due to anticipated floods at a specific future time, or during a
specific time interval. Flood warning, on the other hand, is the dissemination of forecasts
to concerned authorities and to the general public with additional information attached to
it, such as recommendations or orders for action. Flood warning is therefore a decision
making process, which should take into account not only the forecasts but also the
economical and social consequences. The benefits from warnings can be achieved only if
they are timely, accurate, reliable and credible to the receivers, be they government
agencies, businesses or private citizens.