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Nearshore Wave Prediction System

1NOAA Industry Day 2018, Oct 4, Annapolis, MD

André van der Westhuysen1,2

1NOAA / National Weather ServiceNational Centers for Environmental Prediction

2I.M Systems Group, Rockville, MD

Climate/WeatherLinkage

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Intro: Seamless Suite of Weather Forecast Products

Data types and access

• High-resolution (5 km – 200 m) fields of:• Official forecast wind field • Significant wave height• Mean wave direction• Mean wave period• Global model current fields

• Fields of individual wave systems• Future: Rip Current and Erosion/Overwash hazards• Example viewer: NWPS validation viewer• Data access:

ftp.ncep.noaa.gov/pub/data/nccf/com/nwps/prod/

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Ocean waves and Coastal downscaling

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Coastal application

• Desired resolution: 1.8 km - 200 m• Hourly output, out to 6 days• Forecaster consensus wind forcing

http://polar.ncep.noaa.gov/nwps/para/viewer.shtml

Nearshore Wave Prediction SystemSWAN-based operational coastal wave model

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Example NWPS output

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Hawaii

Oahu, HI

Kotzebue Sound,

AK

Juneau, AK

Columbia River

Mouth, OR

On-demand run triggering

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Blue: Southern and Eastern Regions

Red: Western, Pacific and Alaska Regions Total runs: ~90/day

Avg. run times = 30-150 min

Example output: Baltimore/WashingtonForecast wind field, generated wave field

http://polar.ncep.noaa.gov/nwps/

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Validation: Baltimore/WashingtonPatapsco, MD

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Wave-current interactionExample: Miami, FL

http://polar.ncep.noaa.gov/nwps/

Surface currents from NOAA’s global circulation model RTOFS

Coastal wave response

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Inclusion of tide and surge water levelsHurricane Irma (2017/09/11)

Hurricane wind field

Tide + wind surge(ESTOFS model)

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Dealing with complexity: Wave systemsML clustering, e.g. Monterey, CA (2 systems)

Hs, sys1

Hs, sys2

Tp, sys1

Tp, sys2

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Hs, sys1

Hs, sys2

Hs, sys3

Hs, sys4

Hs, sys5

Tp, sys1

Tp, sys2

Tp, sys3

Tp, sys4

Tp, sys5

Dealing with complexity: Wave systemsML clustering, e.g. Los Angeles, CA (5 systems)

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Future: Erosion/overwash guidanceHurricane Irma (2017/09/11)

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Future: Rip Current guidanceExample Cape Cod/Boston, MA

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http://polar.ncep.noaa.gov/nwps/para/viewer.shtml

1. Nearshore Wave Prediction System provides on-demand, high-resolution wave model output. Spatial resolution: 2 km – 200 m. Temporal resolution: Hourly, out to 6 days.

2. Coverage for all of Continental US, Alaska, Hawaii and Puerto Rico.

3. Wave model takes into account official forecast winds, offshore surface currents, tide & surge water levels.

4. Output includes basic wave parameters, wave systems, and in future rip current and erosion/overwash guidance.

5. Model visualizations at (non-operational): polar.ncep.noaa.gov/nwps/viewer.shtml

6. Contact: Andre.VanderWesthuysen@noaa.gov.

Summary

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