Outputs from a Regional Ocean Modeling System (ROMS) data assimilative reanalysis (version DopAnV3R3-ini2007) of ocean circulation in the Mid-Atlantic Bight and Gulf of Maine for 2007-2021

Date 2022-07-27
Temporal extent 2007-01-02 -2021-12-29
Author(s) Wilkin JohnORCID1, Levin Julia1
Affiliation(s) 1 : Rutgers, The State University of New Jersey
DOI 10.17882/89673
Publisher SEANOE
Keyword(s) coastal ocean, ocean circulation model, data assimilation, ROMS, 4D-Var, Mid-Atlantic Bight, Gulf of Maine
Abstract

A 15-year reanalysis (2007-2021) of circulation in the coastal ocean and adjacent deep sea of the northeast U.S. continental shelf has been computed using the Regional Ocean Modeling System (ROMS) and four-dimensional variational (4D-Var) data assimilation (DA) of observations from satellites, land-based ocean surface current measuring radar, and all available in situ observations from the MARACOOS (maracoos.org) and NERACOOS (neracoos.org) regional associations of the U.S. Integrated Ocean Observing System (IOOS). The reanalysis downscales open boundary information from the Copernicus Marine Environmental Monitoring Service (CMEMS) global analysis. The dynamic model is forced by regional meteorological analyses, observed daily river discharges, and harmonic tides that augment the open boundary conditions. The analysis covers the period 2-Jan-2007 to 29-Dec-2021 on a 7-km horizonal grid with 40 vertical terrain-following s-coordinate levels. Ocean state variables computed are sea level, velocity, temperature, and salinity. Air-sea fluxes of heat and momentum, and surface and bottom stresses, are included.

The ROMS 4D-Var DA configuration and its performance in comparison to observations (both assimilated and independent) are described in detail by Wilkin et al. (2022). The underlying ROMS ocean circulation model configuration is described by López et al (2020). Wilkin et al. (2022) also compare this analysis to CMEMS and the U.S. Navy Global Ocean Forecast System (GOFS) HYCOM model.

This dataset is identified as Doppio Analysis Version 3 Release 3 (DopAnV3R3-ini2007) initialized January 2007. It supersedes version DopAnV2R3-ini2007 (Wilkin and Levin, 2021).

The reanalysis outputs comprise more than 7 TB of data, so the files available for direct download here are examples only. The full reanalysis is accessible via a THREDDS (Thematic Real-time Environmental Distributed Data Services) web service that supports geospatial and temporal sub-setting at https://tds.marine.rutgers.edu/thredds/roms/doppio/catalog.html. Access protocols supported are OPeNDAP, WMS and netCDF subsetting.

All ROMS model outputs are in netCDF format and the data and metadata follow CF-1.4 Conventions for the description of coordinates and variables. The reanalysis results are provided on the model’s native 3-D grid in terrain-following coordinates aggregated into six collections:


  • 1-hourly history snapshots for 02-Jan-2007 01:00 through 29-Dec-2021 00:00

  • daily averages for 02-Jan-2007 12:00 through 28-Dec-2021 12:00

  • monthly averages for 17-Jan-2007 through 15-Dec-2021

  • yearly averages for 2007 through 2021

  • monthly ensemble averages

  • daily average analyzed surface fluxes for 02-Jan-2007 12:00 through 28-Dec-2021 12:00 

The observations that were assimilated, after quality control and the formation of super-observations as described by Wilkin et al. (2022), can be accessed via an ERDDAP service at https://tds.marine.rutgers.edu/erddap/tabledap/DOPPIO_REANALYSIS_Ver3_OBS.graph. The dataset includes observation type and provenance fields (documented in the ERDDAP metadata) that allow sub-selection by data types (temperate, salinity, velocity, etc.) or observing platform (e.g., Jason altimeter satellite, AVHRR SST, IOOS gliders, etc.). The ERDDAP catalog includes outputs of the DA system in observation space; namely, prior and posterior model errors, and the CMEMS and GOFS values interpolated to the observation position. An observation scale field flags data that were rejected by 4D-Var QC. 

References cited in the abstract:

López, A., J. Wilkin and J. Levin, (2020) Doppio – a ROMS (v3.6)-based circulation model for the Mid-Atlantic Bight and Gulf of Maine: configuration and comparison to integrated coastal observing network observations, Geosci. Model Dev., 13, 3709–3729, https://doi.org/10.5194/gmd-13-3709-2020

Wilkin J., and J. Levin (2021). Outputs from a Regional Ocean Modeling System (ROMS) data assimilative reanalysis (version DopAnV2R3-ini2007) of ocean circulation in the Mid-Atlantic Bight and Gulf of Maine for 2007-2020. SEANOE. https://doi.org/10.17882/86286

Wilkin, J., J. Levin, A. Moore, H. Arango, A. López and E. Hunter (2002), A data-assimilative model reanalysis of the U.S. Mid Atlantic Bight and Gulf of Maine: Configuration and comparison to observations and global ocean models, unpublished manuscript, submitted to Progress in Oceanography

Licence CC-BY
Data
File Size Format Processing Access
ROMS history file (snapshot) for 2018-02-15 06:00 156 MB NC, NetCDF Processed data Open access
ROMS 24-hour average file for 2018-02-15 44 MB NC, NetCDF Processed data Open access
ROMS monthly mean file for 2018-02 43 MB NC, NetCDF Processed data Open access
ROMS annual mean file for 2018 43 MB NC, NetCDF Processed data Open access
ROMS ensemble monthly mean file for February (from years 2007 through 2020) 43 MB NC, NetCDF Processed data Open access
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How to cite 

Wilkin John, Levin Julia (2022). Outputs from a Regional Ocean Modeling System (ROMS) data assimilative reanalysis (version DopAnV3R3-ini2007) of ocean circulation in the Mid-Atlantic Bight and Gulf of Maine for 2007-2021. SEANOE. https://doi.org/10.17882/89673