Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

DSD-INT 2019 wflow and the River Suir operational flood forecasting system, Republic of Ireland - Verkade

142 views

Published on

Presentation by Jan Verkade, Deltares, at the wflow - User Day (Developments in distributed hydrological modelling), during Delft Software Days - Edition 2019. Friday, 08 November 2019, Delft.

Published in: Software
  • Be the first to comment

  • Be the first to like this

DSD-INT 2019 wflow and the River Suir operational flood forecasting system, Republic of Ireland - Verkade

  1. 1. wflow and the River Suir operational flood forecasting system, Republic of Ireland Dr Jan Verkade, Bob van Rongen, Deltares Delft, November 8, 2019
  2. 2. wflow and the Suir forecasting system – summary • A wflow-HBV model was developed as an alternative to the existing semi-lumped models • … continuous soil-moisture accounting rather than event-based model • … allowing for future use of data-assimilation • Streamflow data assimilation results in an increase of forecast quality • Projected developments include • … data-assimilation of satellite estimates of soil moisture • … more appropriate rainfall interpolation technique
  3. 3. Brief introduction: Jan Verkade • Hydrologist; expert in real-time hydrological forecasting • Member of the Rijkswaterstaat River Forecasting Service • Author of PhD dissertation “Estimating real-time predictive hydrological uncertainty” (2015) • Research interests: • real-time hydrological forecasting • uncertainty analyses; probabilistic forecasting • forecast verification • forecast use http://bit.ly/verkade2015dissertation
  4. 4. Clonmel, Co Tipperary, Ireland Clonmel town
  5. 5. Clonmel, Co Tipperary, Ireland, early September 2015
  6. 6. Clonmel, Co Tipperary, Ireland, October 2011
  7. 7. December 2015 precipitation events (Storms Desmond, Frank)
  8. 8. … these were required to protect the town from flooding Photo credit: Joseph O’Dwyer, Tipperary Co Council … but they take some time to be mounted (‘some time’ >> concentration time of the basin)
  9. 9. Clonmel, Co Tipperary, Ireland, late December 2015 Photo credit: Joseph O’Dwyer, Tipperary Co Council
  10. 10. Forecast – warning – response chain Source: Verkade, J. S. ‘Estimating Real-Time Predictive Hydrological Uncertainty’. Ph.D. dissertation, Delft University of Technology, 2015. http://dx.doi.org/10.4233/uuid:a7e8ac36-4bdb-4231-a11e- d46778b2ae4a Suir AFFS
  11. 11. How is a hydrological forecast produced?
  12. 12. 14 gauged sub-basins Thurles (16004) Athlummon (16001) Beakstown (16002) New Bridge (16008) Rathkennan (16003) Aughnagross (16005) Ballinaclogh (16006) Caher Park (16009) Killardry (16007) Tar (@Tar Br, 16012) Newcastle Bridge (16137) Nire (@Fourmilewater, 16013) Suir (@Clonmel, 16011) Knocklofty (16139)
  13. 13. wflow case: the Suir catchment • semi-lumped catchment models in place: the “14-split URBS model” • very reasonable results. • Challenges: • transitioning from dry to wet period. • limited ability to apply data assimilation techniques Ongoing research project: • Set up a distributed hydrological model: wflow – HBV • Allows for ingesting of remotely senses data, e.g. catchment wetness
  14. 14. the wflow Suir model Fully-distributed HBV conceptual rainfall-runoff model: • wflow framework (wflow-HBV) • Grid size of 500x500 m • Distribution of topography, land cover, soil types & input forcing data
  15. 15. Calibration and validation data Data for HBV model: • Precipitation (P) • Temperature (T) • Potential evapotranspiration (PET) → Direct shortwave radiation → Makkink equation MÉRA (Met Éireann Re-Analysis): • High resolution regional climate reanalysis for Ireland using HARMONIE-AROME • From 1981 to present • Hourly timestep
  16. 16. Calibration approach: “Lumped to distributed” • Use single parameter values across any of the sub-basins as starting point for parameter optimization
  17. 17. https://doi.org/10.1016/j.jhydrol.2009.02.021
  18. 18. “Unsatisfactory” results for Fourmilewater basin • Prompted student to look further • Found: Streamflow @ Fourmilewater > (2 x Precip @ Fourmilewater’s catchment) • Root cause: rainfall interpolation • Inverse Distance based spatial interpolation • Does NOT take into account presence of Knockmealdown mountain range • Which DOES have an effect on the spatial distribution of precip • We drafted a student research project to apply a more physics-based approach: genRE Intermezzo – on precipitation estimates
  19. 19. Intermezzo – on precipitation estimates
  20. 20. Intermezzo – on precipitation estimates
  21. 21. Student assignment • “Application of the genRE approach to spatial interpolation of precipitation gauge data” • Assignment has been drafted and distributed to various Dutch, Irish universities • Applications to • Suir basin, using OPW telemetry network • ROI, using Met Éireann’s telemetry network • In both cases, develop ‘background grid’ using MÉRA Intermezzo – on precipitation estimates
  22. 22. Data assimilation: the principles Observations available up to ~now Last update run ran at midnight; note the model drift Forecast run starts at end of update run However: this means that some model drift is present at t0 also: • doesn’t look great • Possible solution: data assimilation
  23. 23. Data assimilation • Real-time forecasting: recent/current data may be available • Q: how to effectively use this in the forecasting process • A: data assimilation techniques • Input updating • State updating • Parameter updating • Output updating = error correction www.openda.org
  24. 24. Suir AFFS / wflow – projected developments • Include data-assimilation procedures in operational system • Explore assimilation of satellite observations of soil moisture
  25. 25. wflow and the Suir forecasting system – summary • A wflow-HBV model was developed as an alternative to the existing semi-lumped models • … continuous soil-moisture accounting rather than event-based model • … allowing for future use of data-assimilation • Streamflow data assimilation results in an increase of forecast quality • Projected developments include • … data-assimilation of satellite estimates of soil moisture • … more appropriate rainfall interpolation technique
  26. 26. Jan Verkade jan.verkade@deltares.nl, +31 6 5161 6107 Thank you for your attention!

×