Datasets

ROMS-Tools relies on several external datasets. Some are accessed automatically; others must be downloaded manually before running ROMS-Tools.

Dataset	Required for	Download needed	Access
ETOPO5	Grid (Topography)	No (auto-downloaded)	NOAA
SRTM15	Grid (Topography, high-resolution)	Yes	UCSD
EMODnet	Grid (Topography, high-resolution)	Yes	EMODnet
Natural Earth	Grid (Land-Sea Mask)	No (auto-downloaded)	Natural Earth
GSHHG	Grid (Land-Sea Mask, high-resolution)	Yes	SOEST
TPXO	Tidal Forcing	Yes	OSU
GLORYS	Initial & Boundary Conditions	Yes	Copernicus Marine
Unified BGC Dataset	BGC Initial, Boundary & Surface Forcing	Yes	Google Drive
ERA5	Surface Forcing	Optional (streaming supported)	Climate Data Store
Dai & Trenberth	River Forcing	No (auto-downloaded)	NCAR RDA
WOA	Surface Restoring Forcing, sea surface salinity (sss)	Yes	WOA, NOAA
MBL_co2	Time-varying CO2, Surface Forcing	No (auto-downloaded)	MBL, GML, NOAA
SODA	Surface Restoring Forcing, sea surface salinity (sDIC, sALK)	No (auto-downloaded)	OceanSODA-ETHZ, NOAA

Manual Downloads

SRTM15

High-resolution 1/240° global topography dataset. As an alternative, ROMS-Tools can use ETOPO5 at coarser 1/12° resolution, which is downloaded automatically.

Version:

V2.6

Required for:

Grid (Topography)

Available at:

UCSD SRTM15+ Product

Required fields

Field	Description
lat	Latitude (degrees north)
lon	Longitude (degrees east)
z	Topography (m)

EMODnet

European high-resolution bathymetry dataset. An alternative to SRTM15, particularly well-suited for domains in European waters.

Required for:

Grid (Topography)

Available at:

EMODnet Digital Bathymetry

Required fields

Field	Description
lat	Latitude (degrees north)
lon	Longitude (degrees east)
elevation	Bathymetry/topography (m)

GSHHG

Global coastline shapefiles, provided at five resolutions:

• f (full): original highest-detail dataset

• h (high): ~80% reduction in detail and file size

• i (intermediate): another ~80% reduction

• l (low): another ~80% reduction

• c (crude): another ~80% reduction

The full-resolution (f) dataset is recommended for accurate representation of fjords, narrow straits, and other complex coastal geometries.

Alternatively, ROMS-Tools supports Natural Earth coastlines for land-sea mask generation, which are downloaded automatically.

Version:

V2.3.7

Required for:

Grid (Land-Sea Mask)

Available at:

GSHHG Product

For download instructions see Download Instructions.

Required fields

Coastline polygons/lines (Level-1 shapefiles: GSHHS_*_L1.shp and companion files).

TPXO

Global barotropic tidal model providing tidal potential, elevation, and velocities including self-attraction and loading (SAL) corrections.

Supported versions:

TPXO9v5a, TPXO10v2, TPXO10v2a (all 1/6°)

Required for:

Tidal Forcing

Available at:

OSU TPXO Tide Models

Required fields

Field	Description
lat_z, lon_z	Latitude/longitude of z nodes
lat_u, lon_u	Latitude/longitude of u nodes
lat_v, lon_v	Latitude/longitude of v nodes
mz, mu, mv	Water/land mask for z, u, v nodes
hRe, hIm	Tidal elevation, real and imaginary parts (m)
URe, UIm	Tidal transport WE, real and imaginary parts (m²/s)
VRe, VIm	Tidal transport SN, real and imaginary parts (m²/s)

GLORYS

1/12° global ocean physics reanalysis providing physical ocean initial and boundary conditions.

Required for:

Initial Conditions, Boundary Forcing

Available at:

Copernicus Marine Data Store

For download instructions see Download Instructions.

Required fields

Field	Description
time	Time
latitude	Latitude (degrees north)
longitude	Longitude (degrees east)
depth	Depth (m)
zos	Sea surface height (m)
thetao	Temperature (°C)
so	Salinity (psu)
uo	Eastward velocity (m/s)
vo	Northward velocity (m/s)

Unified BGC Dataset

A unified biogeochemical climatology integrating multiple observational and model-based sources, including World Ocean Atlas nutrients, GLODAPv2 carbon chemistry, and CESM model output.

Required for:

BGC Initial Conditions, BGC Boundary Forcing, BGC Surface Forcing

Available at:

Google Drive

For download instructions see Download Instructions.

WOA Salinity Data

A collection of salinity (and other variables) means based on profile data from the World Ocean Database (WOD). The s_an variable provided is the ‘Objectively analyzed mean fields for sea_water_salinity’.

Required for:

Surface Forcing (Restoring Forces; Salinity)

Available at:

NOAA website

For download instructions see Download Instructions.

Required fields

Field	Description
time	Time
lat	Latitude (degrees north)
lon	Longitude (degrees east)
depth	Depth (m)
s_an	Objectively analyzed mean sea_water_salinity (PSU)

Automatically Accessed

ETOPO5

Global 1/12° topography dataset. Downloaded automatically by ROMS-Tools as a coarser alternative to SRTM15.

Required for:

Grid (Topography)

Available at:

NOAA ETOPO Global Relief Model

Required fields

Field	Description
lat	Latitude (degrees north)
lon	Longitude (degrees east)
topo	Topography (m)

Natural Earth

1:10m coastline dataset, used to generate the land-sea mask. The label 1:10m refers to a map scale of 1:10,000,000, which corresponds to an effective spatial resolution of approximately 1–5 km. Accessed automatically via the regionmask package — no file download required.

Required for:

Grid (Land-Sea Mask)

Available at:

Natural Earth

ERA5

Global 1/4° atmospheric reanalysis from ECMWF providing meteorological surface forcing. ROMS-Tools can stream ERA5 data directly from the cloud, so downloading is optional.

Required for:

Surface Forcing

Available at:

Copernicus Climate Data Store

Required fields

Field	Description
time	Time
latitude	Latitude (degrees north)
longitude	Longitude (degrees east)
u10	10 m U wind component (m/s)
v10	10 m V wind component (m/s)
ssr	Surface net short-wave radiation (W/m²)
strd	Surface long-wave radiation downwards (W/m²)
t2m	2 m temperature (K)
d2m	2 m dewpoint temperature (K)
tp	Total precipitation (m)
sst	Sea surface temperature (K) — used for land masking

Dai & Trenberth

Monthly coastal river discharge climatology. Downloaded automatically by ROMS-Tools.

Version:

2019

Required for:

River Forcing

Available at:

NCAR RDA

Required fields

Field	Description
station	Station index
time	Time
lat_mou	River mouth latitude
lon_mou	River mouth longitude
FLOW	Monthly mean volume at station
ratio_m2s	Ratio of volume between river mouth and station
riv_name	River name
vol_stn (optional)	Annual volume at station

MBL_co2

Marine boundary layer values for CO2 (µmol mol⁻¹). Data are from a collection of NOAA’s atmospheric sampling sites, and available about weekly. Data are available for 1979 to 2025. Downloaded automatically by ROMS-Tools.

Version:

2019

Required for:

River Forcing

Available at:

NOAA’s GML, MBL

OceanSODA

A global gridded marine carbonate system dataset calculated from machine learning estimates of Total Alkalinity and the fugacity of carbon dioxide. Data taken from NOAA’s OceanSODA-ETHZ version 2025. Monthly data for years 1982-2024 at 1 degree resolution for the surface water. Downloaded automatically by ROMS-Tools.

Version:

2025

Required for:

Surface Forcing (Restoring Forces; DIC & ALK)

Available at:

NOAA’s OceanSODA

Download Instructions

• Download Instructions
• Dataset Read Guidelines