OceanPredict’19

Validation of the NCEP WAVEWATCH III® Global Wave Model

Deanna Spindler, Todd Spindler, Stylianos Flampouris

Deanna.Spindler@noaa.gov 1

IMSG at EMC/NCEP/NOAA

OceanPredict ‘19GODAE OceanView Symposium

6-10 May 2019, Halifax, Canada

OceanPredict’19

Validation of the NCEP WAVEWATCH III® Global Wave Model

Deanna Spindler, Todd Spindler, Stylianos Flampouris

Deanna.Spindler@noaa.gov 2

IMSG at EMC/NCEP/NOAA

OceanPredict ‘19GODAE OceanView Symposium

6-10 May 2019, Halifax, Canada

“All models are wrong, but some are useful” – George E.P.Box

Outline▪ Quick introduction to the operational multigrid

WAVEWATCH III®▪ The validation goal and process▪ Buoy Validation

▪ Monthly, “Daily” or Event driven▪ Time series: Bias, RMSE, Cross-Correlation, Scatter Index▪ Scatter and Quantile-Quantile plots▪ Taylor Diagrams

▪ Altimeter Validation▪ Individual satellites: Along track

▪ Summary and future plans

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Operational WW3: Multi-1

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Global WAVEWATCH III model with two-way nested grids

– Eight rectilinear grids• Resolutions of 1/2 to

1/12 degree– North PolarStereo grid

• 18 km resolution

– Driven by GFS winds and NCEP 1/12 ice analysis

- Runs side by side with the atmospheric GFS model

4 cycles a day: 9 h hindcasts, 180 h forecast

- Currently there is no data assimilation – soon to change

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The Goal

• Provide validation of the significant wave height, 10m wind speed, wave peak period, and eventually wave spectra

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The Process• Measurement preparation:

time series of data collocated in space and time

• Generate: tables of stats, error metrics, graphical output, and websites to display everything

Buoy Validation

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Geographical coverage is limitedDeep versus shallow waterData needs to be quality controlled

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Monthly Validation

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Monthly Scatter and Q-Q Plots

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Q-Q plot for March

Scatterfor

March

Scatterfor

February

Monthly Taylor Diagrams

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Tp

Click on a Taylor Diagram to zoom

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Event driven: Buoy validation

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Event driven: Altimeter validation

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• Add the along-track altimeter validation to the websites• Add new altimeter scatter plots:

- Against all available satellite data for an area- As a function of distance from a shore or from a storm- As a function of water depth

• Add spectra validation and new metrics• Data assimilation begins..

What is next?

Summary

• Different websites show the buoy validation for the global operational waves model, allowing us to monitor the model performance either in near-realtime or at the end of the month

• Along-track altimeter validation is performed for specific events or storms

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Thank you!

Any Questions?

WW3 Multi-1 Grids

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Global: 77 S to 77 N

10 minute resolution30 minute resolution

4 minute resolution

Arctic: 65 N to 82 N

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Monthly Quantile-Quantile Plots

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What is next: Verification against all Satellites

Figures courtesy of Ali Abdolali

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Also next: Scatter as a function of

Distance

Depth

Figures courtesy of Ali Abdolali

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