Book contents
- Frontmatter
- Contents
- Contributors
- Editors' preface
- Keynote address to the 1977 Symposium SIR JAMES LIGHTHILL
- Part I The large-scale climatology of the tropical atmosphere
- Part II The summer monsoon over the Indian subcontinent and East Africa
- Part III The physics and dynamics of the Indian Ocean during the summer monsoon
- Part IV Some important mathematical modelling techniques
- Part V Storm surges and flood forecasting
- 44 Storm-surge prediction using numerical models
- 45 Numerical simulation of storm surges in the Bay of Bengal
- 46 Flood stage forecasting in rivers
- Index
46 - Flood stage forecasting in rivers
Published online by Cambridge University Press: 05 November 2011
- Frontmatter
- Contents
- Contributors
- Editors' preface
- Keynote address to the 1977 Symposium SIR JAMES LIGHTHILL
- Part I The large-scale climatology of the tropical atmosphere
- Part II The summer monsoon over the Indian subcontinent and East Africa
- Part III The physics and dynamics of the Indian Ocean during the summer monsoon
- Part IV Some important mathematical modelling techniques
- Part V Storm surges and flood forecasting
- 44 Storm-surge prediction using numerical models
- 45 Numerical simulation of storm surges in the Bay of Bengal
- 46 Flood stage forecasting in rivers
- Index
Summary
Two case studies of flood stage prediction are described using a model based on state variables. In the first case, flood stages on the Brahmaputra river are predicted using stage data as input to the model with its parameters estimated by the extended Kalman filter algorithm. In the second case, flood stage forecasting on the Wainganga river is carried out using rainfall as the input. The parameters of the model in this case are estimated by the recursive least-square algorithm.
Introduction
Forecasting is, by definition, the art of estimating the probable behaviour of a phenomenon. Its accuracy depends upon the nature of the phenomenon, the nature of the available data and the adequacy of the fitted model. Hydrologists are commonly required to forecast the time development of hydrologic phenomena such as runoff, floods and rainfall. These phenomena are complex in nature and their distribution both spatial and temporal.
In India, where the terrain is highly irregular, the rainfall distribution during the year is highly skewed, 75%; of rainfall being received during the monsoon months June to September. The rainfall of the country as a whole is less variable from year to year (±10%; of the annual mean) but it is extremely variable from month to month. This seasonal variability in Indian rainfall is responsible for causing floods or droughts in some parts of the country almost every year.
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- Chapter
- Information
- Monsoon Dynamics , pp. 707 - 718Publisher: Cambridge University PressPrint publication year: 1981