Data Portal

We are pleased to share Salish Sea Model (SSM) solutions generated through our model development efforts over the years. The SSM is a research tool developed by the Pacific Northwest National Laboratory in collaboration with the Washington State Department of Ecology and the U.S. EPA. It is used by the University of Washington students, faculty, and the Salish Sea research community. The model and the solutions have been tested against monitoring data to meet performance standards but are not perfect by any means. They are continually improved upon and must be treated and used in that spirit.

SSM Hindcasts – 2013 to Present

The SSM (intermediate scale version, 16012 nodes and 10 layers) hindcast solutions from Year 2013 to present are provided below for download and use by the user community. Regionwide average model validation and skill assessment information is also provided alongside. Users are referred to Khangaonkar et al. (2018) and Khangaonkar and Yun (2023) for more details.

Each year consists of (1) SSM hydrodynamic model (HYD) folder with results generated by the FVCOM model application; and (2) SSM Water Quality Model (WQM) folder with results generated by the FVCOM-ICM model application. The hydrodynamic solutions in netcdf format include water surface elevation, currents (u,v), temperature (T) and salinity (S) at an hourly interval along with additional information related to turbulence and mixing. The water quality solutions include numerous biogeochemical parameters including T, and S, dissolved oxygen (DO), pH, total alkalinity, dissolved inorganic carbon, algal biomass of diatoms, dinoflagellates, organic and inorganic forms of nutrients (N,P), detritus as particulate and dissolved organic carbon, and zooplankton. These netcdf files correspond to each day in the calendar year with 24 hourly records.

SSM_HR or SSCOFS Hindcasts – selected years

Hindcast solutions from the Salish Sea Model – high resolution version SSM_HR (239,734 nodes and 10 layers) which has been incorporated into the Salish Sea and Columbia River Operational Forecast System (SSCOFS) are presented below. Regionwide average model validation and skill assessment information is also provided alongside. Users are referred to Premathilake and Khangaonkar (2023) for more details. Each year consists of SSM_HR hydrodynamic model (HYD) folder with results generated by the FVCOM model application.

The Salish Sea Model 2.0 (SSM2.0) 2017 model solution is provided below for download and use by the user community. SSM2.0 represents a major upgrade of the previous FVCOM-based Salish Sea Model through implementation of the SCHISM modeling framework with the Localized Sigma Coordinates with Shaved Cell (LSC2) formulation. The model uses up to 25 vertical LSC2 layers, retains the original unsmoothed bathymetry, and extends the model domain approximately 134 km farther offshore beyond the continental shelf break. These improvements reduce pressure gradient errors associated with steep bathymetry and improve the representation of stratification, currents, temperature, and circulation in narrow channels, steep slope regions, and shallow intertidal areas. Users are referred to the associated SSM2.0 publication for details on model development, calibration, and skill assessment.

SSM2.0 – Next Generation Salish Sea Model in high resolution using SCHISM

SSM2.0 is a major upgrade of the Salish Sea Model in high resolution. In this version, the computational engine has been updated from FVCOM to SCHISM. The bathymetric smoothing approximation, a limitation of the prior versions, has been eliminated. With the use of original bathymetry a corresponding improvement in performance has been realized. The existing vertical resolution has been improved from 10 σ-layers to a maximum of 25-LSC2 (local sigma with shaved cells) layers and the domain expanded 134 km further offshore from the shelf break. The model has been calibrated using year 2017 conditions, and the skill assessed to confirm no drop-off in performance in reproducing stratification and expected improvement in predictions of currents and temperature from the upgrade (see Khangaonkar et al. (2026) “Simultaneous resolution of near-shore intertidal and deep estuarine circulation by eliminating bathymetric smoothing in modeling – the Salish Sea,” Ocean Dynamics, 76, 42). The 2017 SSM2.0 solution is provided as daily NetCDF files organized by model variable. The available datasets currently include east-west velocity (VelX), north-south velocity (VelY), salinity, and temperature, and water surface elevation with 365 files provided for each variable corresponding to the calendar year. These model outputs are intended to support analysis of Salish Sea hydrodynamics and provide a higher-fidelity representation of circulation and hydrodynamic conditions across U.S. and Canadian waters of the Salish Sea.

Future Climate Projections for the Salish Sea, CMIP5 high emissions (RCP8.5) scenario

Future climate projections for the Salish Sea were computed using SSM, based on input and forcing files constructed by dynamic downscaling of CMIP5 Global Climate Model experiments in the IPCC fifth assessment. In this context, YR2000 corresponds to the historic run and is a 10-year 3-ensemble member average centered around YR2000. YR2095 is a future projection under IPCC RCP8.5 high-emissions scenario, and is also a 10-year 3-ensemble member average, but centered around YR2095. A relative sea level rise of 1.5 m is included. The simulations include coupled hydrodynamic and biogeochemical processes including nutrients, phytoplankton, zooplankton, and submerged aquatic vegetation. Users are referred to Khangaonkar et al. (2021), “Projections of algae, eelgrass, and zooplankton ecological interactions in the inner Salish Sea – for future climate, and altered oceanic states,” Ecological Modelling, 441, 109420, for additional details on the model configuration, analysis, and projected ecological responses. Each year includes hydrodynamic (HYD) and water quality/biogeochemical (WQM) model solutions provided in NetCDF format. The model outputs include physical variables such as currents, temperature, and salinity, together with biogeochemical variables used to assess dissolved oxygen, pH, carbonate chemistry, nutrients, plankton dynamics, and submerged aquatic vegetation.

How to Download SSM Data Files

You can download SSM data files in two ways. If you are not familiar with coding, simply use the links in the table above to download files one by one. For users who prefer automation or want to download multiple files at once, Python, wget, or curl can be used. In Python, this can be done easily with a for loop that goes through a list of file URLs or filenames. Examples of each method are shown below.

Download using Python

import urllib.request
url = "https://s3.kopah.uw.edu/ssm/hyd/2013/ssm_0001.nc"
urllib.request.urlretrieve(url, "ssm_0001.nc")
print("Downloaded to ssm_0001.nc")

Download using wget

wget https://s3.kopah.uw.edu/ssm/hyd/2013/ssm_0001.nc

Download using curl

curl -O https://s3.kopah.uw.edu/ssm/hyd/2013/ssm_0001.nc

Oil Spill Modeling in the Salish Sea using the Salish Sea Model (SSM) and General NOAA Operational Modeling Environment (GNOME)

• A Demonstration Package Prepared for Education and Outreach

Salish Sea Modeling Center (SSMC) in consultation with the Education Coordinator for the SeaDoc Society, created this package for teaching demonstrations and use by middle and high school teachers and their students. The model solution is provided solely for educational and research purposes; any use of the model solution beyond the intended scope must be approved by SSMC. No rights in the underlying intellectual property, beyond the grant of this permissive research license, is provided herein. The user assumes responsibility for the model use, misuse, or inability to use the model solution and in no event shall SSMC have any liability for damages, including but not limited to any indirect, incidental, or consequential damages, arising from or in connection with the use of the model solution. Contact Tarang Khangaonkar for more information.

Download the ZIP file here (70 MB). Instructions are in the SSMC_ReadMe text file.

FILE

SSM-GNOME oil spill modeling teaching demonstration package