# Presentation: 656270

## An Unstructured Grid, Finite-Volume Coastal Ocean Model (FVCOM), Global-Regional-Coastal-Estuarine Applications

- Robert C. Beardsley, Changsheng Chen and Geoffrey Cowles

- http://fvcom.smast.umassd.edu

## Outline

- Introduction to FVCOM
- Multiscale applications
- Northeastern Regional Association of Coastal Ocean Observing Systems (NERACOOS)
-          - Northeast Coastal Ocean Forecast System
-            (NECOFS)
-          - Inundation Pilot Study (with NWS)
-                  (Scituate, MA; Saco, ME)
-          - Water Quality (DO) (Long Island Sound)
-          - Observing system design experiments
- Recent FVCOM developments
- NECOFS needs
- Summary

## Critical Issues in Coastal Ocean Modeling

**Critical Issues in Coastal Ocean Modeling**

- Irregular geometry

- Intertidal wetlands

- Steep topography

**Mass Conservation ?**

## Finite-Difference, Finite-Element and Finite-Volume Methods (FDM, FEM, FVM) 

**FEM**

**FVM**

**Finite-Difference, Finite-Element and Finite-Volume Methods (FDM, FEM, FVM)**** **

- Difference

- Variation

- Integration

##  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.

-  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.
- The numerical computational domain consists of non-overlapping unstructured cells.
-  Combines the best from the finite-element method for the geometric flexibility and finite difference method for the simplest discrete computation.
-  Both current and tracer remain the second-order accuracy.

## Upgrading: non-hydrostatic version and semi-implicit version

## Slide 7

## Pan-Arctic Ocean FVCOM 

**Pan-Arctic Ocean FVCOM **

- In the region where the mean water is deeper or equal to 100 m, 10 same thickness layers in the upper 30 m (with a layer thickness from 2 to 5 m) and 5 same thickness layers in the lower 25 m  above the bottom.
- Driven by the OMIP-Forcing-the sixth version and the model starts run at January 1 with the  wintertime fields of water temperature and salinity.
- The water temperature and salinity data were from polar science center _H_ydrographic _C_limatology (PHC) version 3.0.
- The region north of 65oN is covered by the ice with a thickness of 2.5 m everywhere at initial

## Horizontal resolution: 0.3-1.0 km in the coastal region;

- Generalized terrain-following coordinates: 46 layers: 10 uniform layers in the surface and bottom boundary layers, respectively.
- 1500 m cutoff off Georges Bank
- Capable to nest to the coasta-estuarine model with a horizontal resolution of ~10 -500 m;

## Penobscot Bay

**Penobscot Bay**

## Slide 11

## Boston harbor area

## Slide 13

## Slide 14

## Slide 15

## Slide 16

## Northeast Coastal Ocean Forecast System (NECOFS)

**Northeast Coastal Ocean Forecast System (NECOFS)**

## NE Weather Models being used to drive ocean models

| Group | Model | Source | Nesting | Output | Output  | Online |
| --- | --- | --- | --- | --- | --- | --- |
| Stony Brook U | WRF-ARW1 | 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-ARW1 | same | 32-km
9-km (R)
3-km (L) | 3-day@
3-hr | Basic, ASF, RF | Y |
| UNH-AER | ARW-WRF1 | 32-km NAM | 27-km
9-km (R)
3-km (L) | 2-day @
6-hr | Basic, ASF, RF | Y3 |
| UMaine | - | 12-km NAM | - | 2-day@
6-hr | Basic, ASF2 | Y |

- URLs:
- Stony Brook U: _[http://atmos.msrc.sunysb.edu/mm5rt](http://atmos.msrc.sunysb.edu/mm5rt)_
- Stony Brook U: _[http://](http://chaos.msrc.sunysb.edu/NEUS/nwp_graphics.html)__[chaos.msrc.sunysb.edu/NEUS/nwp_graphics.html](http://chaos.msrc.sunysb.edu/NEUS/nwp_graphics.html)_
- UMassD: _[http://fvcom.smast.umassd.edu/research_projects/GB/mm5/index.html](http://fvcom.smast.umassd.edu/research_projects/GB/mm5/index.html)_
- UMassD: _[http://fvcom.smast.umassd.edu/research_projects/GB/WRF/index.html](http://fvcom.smast.umassd.edu/research_projects/GB/WRF/index.html)_
- UNH-AER: _[http://](http://www.jcoot.unh.edu/forecasts/forecasts.html)__[www.jcoot.unh.edu/forecasts/forecasts.html](http://www.jcoot.unh.edu/forecasts/forecasts.html)_
- UMaine: - _[http://](http://www.gomoos.org/)__[www.gomoos.org](http://www.gomoos.org/)__[/](http://www.gomoos.org/)_

**NE Weather Models being used to drive ocean models**

## Large domain: 27 km

- Large domain: 27 km

- Domain 1

- Domain 2

- Domain 2

- Domain 3

- Domain 3

- Local domain: 3 km

- Hindcast

## NECOFS Model Flow Diagram: 1.0

- Stage: 1 (midnight)
- Crontab starts NECOFS

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Day 0 ~ now

- Current Process

- 1:
- 2:
- 3:

- (Previous
- Hindcast)

- (Previous
- Forecast)

**Notes:**
The blue bar represents model time in days relative to the current time. 

## NECOFS Model Flow Diagram: 1.0

- Stage: 2 (midnight)
- Update River Data

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- (Previous
- Forecast)

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1: Download USGS data and update data file
- 2:
- 3:

- (Previous
- Hindcast)

## NECOFS Model Flow Diagram: 1.0

- Stage: 3 (00:10)
- Update SST Data

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1: Download JPL SST and update OI assim
- 2:
- 3:

- S 2

- (Previous
- Forecast)

- (Previous
- Hindcast)

- Latest available SST data is already several days old

## NECOFS Model Flow Diagram: 1.0

- Stage: 4 (00:15)
- Run WRF

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1: WRF Forecast
- 2: WRF Hindcast
- 3:

- S 2

- S 3

- Continuous WRF data archive is automatically updated with new results

- (Previous
- Hindcast)

- (Previous
- Forecast)

## NECOFS Model Flow Diagram: 1.0

- Stage: 5 (08:00)
- Start FVCOM hindcast

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1: WRF Forecast
- 2: FVCOM Hindcast
- 3:

- S 2

- S 3

- FVCOM overwrites old results updating time period of new WRF data.

- S 4

- (Still running)

- (Previous
- Hindcast)

- (Previous
- Forecast)

## NECOFS Model Flow Diagram: 1.0

- Stage: 6 (11:00)
- Start FVCOM Forecast

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1: FVCOM Forecast
- 2:
- 3:

- S 2

- S 3

- S 4

-  S 5

- S 5

- (Previous
- Hindcast)

- (Previous
- Forecast)

- FVCOM forecast runs till end of available WRF data

## NECOFS Model Flow Diagram: 1.0

- Stage: 7 (12:00)
- NECOFS Forecast Finished!

- wrf forecast data

- wrf hindcast data

- fvcom data (results)

- river data

- sst data

- Day#  -10        -5   -4   -3   -2   -1	0	1	2	3

- Current Process

- 1:
- 2:
- 3:

- S 2

- S 3

- S 4

-  S 5

- S 5

- S 6

- New Results are Automatically posted to the web site!

- (Previous
- Hindcast)

- (Previous
- Forecast)

## http://fvcom.smast.umassd.edu

## Slide 28

## Recent Developments 

- Unstructured-grid finite-volume version of CICE model (CICE-ug) – (for Arctic Ocean applications)
- Unstructured-grid finite-volume version of SWAN (ug-SWAN)
- Non-hydrostatic version of FVCOM (NH-FVCOM) (uses  parallelized scalable sparse matrix solver library (PETSc) and high performance pre-conditional HYPRE software library)
- Semi-implicit version of FVCOM (significant speed-up factor of ~10-20)

## NECOFS Needs

- Surface atmospheric forcing:
-      - Basic: winds, Ta, RH, Pa, **P**, **SST**, **SW & LW** radiation, **PAR**
-      - Derived: wind stress, heat flux (**Qsw,Qlw**,**Qsen,Qlat**), **P**-**E **
-        [**ARW; COARE3; ****AVHRR****, ****ISCCP, FLASHFlux (?)**]
- 2.  Boundary conditions for regional coastal ocean model from basin/global models: surface waves [**WAVEWATCH**]; surface elevation, T,S, currents, ...[.....]
- 3.  Coastal boundary conditions: watershed flux of water and nutrients into coastal ocean via surface discharge and groundwater   [USGS, **UNH NE watershed model system**]

## Unstructured-grid finite-volume model (FVCOM) system provides a new community tool to nest global-regional-coastal-estuarine system together, suitable for ocean application, particularly for coastal environmental hindcast/forecast and ecosystem research. 

- Unstructured-grid finite-volume model (FVCOM) system provides a new community tool to nest global-regional-coastal-estuarine system together, suitable for ocean application, particularly for coastal environmental hindcast/forecast and ecosystem research.
- NECOFS are in operation, for more information, visit FVCOM website:
-                     _[http://fvcom.smast.umassd.edu](http://fvcom.smast.umassd.edu/)_