The Northeast Coastal Ocean Forecast System (NECOFS) and Storm Surge and Inundation Prediction. Status and Initial Ideas

Transcription

1 The Northeast Coastal Ocean Forecast System (NECOFS) and Storm Surge and Inundation Prediction Status and Initial Ideas Changsheng Chen (UMassD) and Bob Beardsley (WHOI) Website: Mass CZM July 15, 2008

2 Northeast Coastal Ocean Forecast System (NECOFS) simplified for storm surge and inundation prediction BC s North American Mesoscale Weather Model (NAM 32 km) Satellite SST Buoy Winds Insolation Regional Mesoscale Model (MM5,WRF) Global Wave Model (WAVEWATCH) BC s BC s Heat Flux P-E Wind Stress U,V Form Drag Surface Wave Model (ug-swan) Ocean GCM Global Tidal Model Freshwater Input U,V, Waves, Radiation Stress FVCOM Storm Surge Bottom Stress Satellite SST, U,V Buoy T,S,U,V,P BC s KEY TB Developed Existing Models Core Models Local Inundation Models (FVCOM, ADCIRC,...) Sediment Transport Model (FVCOM USGS module) Data

3 NE weather models being used to drive ocean models Group Model Source Nesting Output Variables Online Stony Brook U WRF- ARW 1 32-km NAM 1- deg NOGAPS1- deg CMC0.5 deg GFS 32-km 12-km (R) 4-km (NAM member) 2-day@ 1-hr 1.5-day for 4-km Basic, ASF, RF Y Stony Brook U MM5 Same as WRF- ARW 32-km 12-km (R) 4-km (NAM member) 2-day@ 1-hr 1.5-day for 4-km Basic, ASF, RF Y UMassD MM5 32-km NAM 30 km 10-km (R) 3-day@ 3-hr Basic, ASF, RF Y UMassD WRF- ARW 1 32-km NAM 32-km 9-km (R) 3-km (L) 3-day@ 3-hr Basic, ASF, RF Y UNH-AER ARW- WRF 1 32-km NAM 27-km 9-km (R) 3-km (L) 6-hr Basic, ASF, RF Y 3 UMaine - 12-km NAM - 2-day@ 6-hr Output Variables: Basic: surface wind, air temperature, RH, pressure, SST Air-Sea Fluxes (ASF): wind stress, sensible heat flux, latent heat flux, E-P Radiative Fluxes (RF): shortwave heat flux, long-wave heat flux, PAR Basic, ASF 2 Y Stony Brook U: Stony Brook U: UMassD: UMassD: UNH-AER: UMaine: -

4 Domain 2 Domain 1 Domain 3 Domain 2 Regional Domain: 9 km Domain 3 Hindcast Local domain: 3 km Large domain: 27 km

5 Example of surface (10-m) wind and pressure

6 Critical Issues in Coastal Ocean Modeling Irregular geometry Mass Conservation? Steep topography Intertidal wetlands

7 Basic Classes of Ocean Model Grids: Structured cartesian (rectangular), orthogonal curvilinear, spherical (examples: POM, ECOM-si, ROMS) Unstructured triangular, trapezoidal (geometric flexibility) (examples: ADCIRC (FE), SELFE FE), Finite-Volume Coastal Ocean Model (FVCOM)

8 FVCOM: Unstructured-grid, Finite-Volume Coastal Ocean Model (Chen, C. R. H. Liu and R. C. Beardsley, JAOT, 2003) All variables are computed in the integral form of the equations, which provides a better representation of the conservative laws of mass, momentum and heat in the coastal region with complex geometry. F u,v u,v F u,v F u,v F u,v u,v F The numerical computational domain consists of non-overlapping unstructured cells. F F F : ", T, S,!, H, K m, K h, etc yʹ Combines the best from the finiteelement method for the geometric flexibility and finite difference method for the simplest discrete computation. u,v u,v u,v u,v Both current and tracer remain the second-order accuracy.

9 NERACOOS regional FVCOM grids Second Generation Third Generation Horizontal resolution: km in the coastal region; Sigma-coordinates: 31 vertical layers 300-m cutoff off Georges Bank Horizontal resolution: km in the coastal region; Generalized terrain-following coordinates: 46 layers: 10 uniform layers in the surface and bottom boundary layers, respectively m cutoff off Georges Bank Capable to nest to the coastal-estuarine model with a horizontal resolution of ~ m;

10

11

12

13

14 NECOFS Model Flow Diagram: 1.0 Stage: 1 (midnight) Crontab starts NECOFS Day 0 ~ now Day# wrf forecast data wrf hindcast data fvcom data (results) river data sst data Current Process 1: 2: 3: (Previous Hindcast) (Previous Forecast)

15 NECOFS Model Flow Diagram: 1.0 Stage: 2 (midnight) Update River Data Day# wrf forecast data wrf hindcast data fvcom data (results) river data sst data (Previous Hindcast) (Previous Forecast) Current Process 1: Download USGS data and update data file 2: 3:

16 NECOFS Model Flow Diagram: 1.0 Stage: 3 (00:10) Update SST Data Latest available SST data is already several days old Day# wrf forecast data wrf hindcast data fvcom data (results) river data sst data S 2 (Previous Hindcast) (Previous Forecast) Current Process 1: Download JPL SST and update OI assim 2: 3:

17 NECOFS Model Flow Diagram: 1.0 Stage: 4 (00:15) Run WRF wrf forecast data Continuous WRF data archive is automatically updated with new results Day# wrf hindcast data fvcom data (results) river data sst data S 3 S 2 (Previous Hindcast) (Previous Forecast) Current Process 1: WRF Forecast 2: WRF Hindcast 3:

18 NECOFS Model Flow Diagram: 1.0 Stage: 5 (08:00) Start FVCOM hindcast FVCOM overwrites old results updating time period of new WRF data. Day# wrf forecast data (Still running) wrf hindcast data fvcom data (results) river data sst data S 3 S 4 S 2 (Previous Hindcast) (Previous Forecast) Current Process 1: WRF Forecast 2: FVCOM Hindcast 3:

19 NECOFS Model Flow Diagram: 1.0 Stage: 6 (11:00) Start FVCOM Forecast FVCOM forecast runs till end of available WRF data Day# wrf forecast data wrf hindcast data fvcom data (results) river data sst data S 3 S 4 S 5 S 2 (Previous Hindcast) S 5 (Previous Forecast) Current Process 1: FVCOM Forecast 2: 3:

20 NECOFS Model Flow Diagram: 1.0 Stage: 7 (12:00) NECOFS Forecast Finished! New Results are Automatically posted to the web site! Day# wrf forecast data wrf hindcast data fvcom data (results) river data sst data S 3 S 4 S 2 S 5 S 5 S 6 (Previous Hindcast) (Previous Forecast) Current Process 1: 2: 3:

21

22

23

24 NECOFS - status 1. Now operational 24/7 in experimental mode 2. Model system description and forecasts available at NECOFS website: 3. Initial applications: a) surface weather and ice forecast data for NWS Taunton WFO; b) surface currents and winds for USCG search and research planning; c) surface forcing and currents in Buzzards Bay for research by USGS, in Nantucket Sound for WHOI/UMassD, in Plum Island Sound by MBL, Mass Bays for MWRA planning. 4. NERACOOS Storm Surge and Inundation project ( )

25 NECOFS storm surge and inundation system Definitions: Storm surge (SS) = surface elevation in model domain with tall walls at coastline (i.e., no flooding and drying) Inundation (In) = surface elevation in coastal region where flooding and drying can occur within model domain Objectives: Produce 3-d forecast of SS and related variables in coastal zone of regional model domain Produce surface and open ocean/land BC s to drive local FVCOM model to produce 3-d forecast of In and related variables Provide data in correct format for distribution through USGS

26 Steps: 1. Run NECOFS 3rd generation 3-D model to produce 3-d forecast of surface forcing, ocean fields 2. Use fields to force 2-D regional storm surge model to produce 3-d storm surge forecast and forcing fields for local inundation models 3. Use 2-D fields to force local 2-D inundation models (Saco, Scituate) 4. Distribute storm surge and inundation forecast results through USGS/GOMOOS 5..

27

28

29 Town Contacts: SACO, Maine Robert C. Bohlmann, Director, York County Emergency Management and Homeland Security Steve Boucouvalas, EMA Director, City Office of Emergency Management SCITUATE, Mass Neil F. Duggan, Scituate Inspection Department Building Zoning Enforcement Officer Other Contacts Wes Shaw, StormSmart Coasts Project Manager, Mass CZM Bob Thompson, Head, Taunton NWS Weather Forecast Office Ed Fratto, Executive Director, Northeast States Emergency Consortium (NESEC)