Flood forecasting
Encyclopedia
Flood forecasting is the use of real-time precipitation
and streamflow
data in rainfall-runoff and streamflow routing models to forecast flow rates and water levels for periods ranging from a few hours to days ahead, depending on the size of the watershed or river basin
.
http://amsglossary.allenpress.com/glossary/browse?s=f&p=18 Flood forecasting can also make use of forecasts of precipitation in an attempt to extend the lead-time available.
Sophisticated flood forecasting systems will also account for the effects of:
To accomplish this, the range of models required needs to include appropriate snowmelt models, and the types of streamflow models that work well for simple applications need the addition of hydrodynamic models.
Flood forecasting is an important component of flood warning
, where the distinction between the two is that the outcome of flood forecasting is a set of forecast time-profiles of channel flows or river levels at various locations, while "flood warning" is the task of making use of these forecasts to make decisions about whether warnings of floods should be issued to the general public or whether previous warnings should be rescinded or retracted.
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
and streamflow
Streamflow
Streamflow, or channel runoff, is the flow of water in streams, rivers, and other channels, and is a major element of the water cycle. It is one component of the runoff of water from the land to waterbodies, the other component being surface runoff...
data in rainfall-runoff and streamflow routing models to forecast flow rates and water levels for periods ranging from a few hours to days ahead, depending on the size of the watershed or river basin
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
.
http://amsglossary.allenpress.com/glossary/browse?s=f&p=18 Flood forecasting can also make use of forecasts of precipitation in an attempt to extend the lead-time available.
Sophisticated flood forecasting systems will also account for the effects of:
- snowmelt;
- flood plains and washlands;
- flood defences, including control-gates etc.;
- tidal effects near the sea, and sea-surges.
To accomplish this, the range of models required needs to include appropriate snowmelt models, and the types of streamflow models that work well for simple applications need the addition of hydrodynamic models.
Flood forecasting is an important component of flood warning
Flood warning
Flood warning is closely linked to the task of flood forecasting. The distinction between the two is that the outcome of flood forecasting is a set of forecast time-profiles of channel flows or river levels at various locations, while "flood warning" is the task of making use of these forecasts to...
, where the distinction between the two is that the outcome of flood forecasting is a set of forecast time-profiles of channel flows or river levels at various locations, while "flood warning" is the task of making use of these forecasts to make decisions about whether warnings of floods should be issued to the general public or whether previous warnings should be rescinded or retracted.
External links
- Delft-FEWS, state of the art system for flood forecasting and operational water management (most advanced system available, used on national scale in Europe and the USA)
- Decision tree to choose an uncertainty method for hydrological and hydraulic modelling, Choosing an uncertainty analysis for flood modelling.
- http://www.waterlog.info/software.htm , RainOff, a conceptual rainfall-runoff model using a nonlinear reservoir.