JRA55-do¶

JRA-55 based surface dataset for driving ocean–sea-ice models (JRA55-do)

Discontinued

At a glance¶

Note on period: v1.6.0 covers "the entire period (01Jan1958-01Feb2024)", i.e. 1 January 1958 to 1 February 2024 00 UTC. Its content is identical to v1.5.0 (to July 2020) joined with its extension v1.5.0.1 (2020 to 2024). OMIP experiments use the 66-year period 1958–2023 as one forcing cycle.

Overview¶

A surface dataset for driving ocean–sea-ice models, made by adjusting the JRA-55 reanalysis surface atmospheric fields toward satellite and other observation-based products. It replaced CORE-II as the standard forcing for phase 2 of OMIP (OMIP-2) and provides, in one package, 3-hourly wind, air temperature, humidity, radiation and precipitation together with river, Antarctic and Greenland freshwater runoff. Its higher resolution and more frequent updates than CORE-II made it widely used in high-resolution ocean modelling.

What changes with the successor¶

JRA55-do → CFORCE Planned¶

Planning-stage information, not an official successor. NCAR, GFDL and LANL are building CFORCE, a next-generation ERA5-based dataset for forcing ocean–sea-ice models. The October 2024 WCRP presentation anticipated availability in early 2026, after which OMIP and LMIP may switch to it; the same presentation noted that CMIP7 OMIP uses JRA55-do because it "goes through 2023". As of October 2026 no data or formal documentation have been released.

Sources: WCRP presentation — Next Generation Datasets for Forcing Ocean/Sea-ice (CFORCE, NSF NCAR, 2024-10) · MRI JRA55-do official page (updates discontinued 2024-01-31, v1.6.0 final)

Available variables¶

Variables from Tables 1 and 2 of the JRA55-do v1.6 User Manual. Names are the CMOR variable names in the input4MIPs files (NetCDF). Atmospheric variables are given at 10 m above the sea surface (not 2 m).

instantaneous mean accumulated maximum minimum static — instantaneous: value at the time stamp · mean/accumulated/maximum/minimum: over the indicated interval · static: does not change with time

Atmospheric forcing (3-hourly, TL319)¶

Freshwater runoff (daily mean, 0.25°)¶

Supplementary data¶

The full variable list is in the official documentation.

How to get the data¶

• ESGF input4MIPs — MRI-JRA55-do-1-6-0 (final version) — ESGF search → per-variable wget scripts / HTTPS No login needed
  • Search facets: mip_era=CMIP6Plus, target_mip=OMIP, institution_id=MRI, source_id=MRI-JRA55-do-1-6-0. For v1.5.0 (1958 to July 2020), look for the CMIP6-era MRI-JRA55-do-1-5-0.
• ESGF ORNL node THREDDS catalog (v1.6.0) — THREDDS / direct HTTPS download No login needed
  • Organised in realm folders atmos, land, landIce, ocean and seaIce.
• MRI server — v1.5.0.1 (2020 to January 2024) — Direct HTTPS download (yearly files) No login needed
  • The post-2020 extension ("a preliminary release extending v1.5.0 to latest"). MRI directs users to input4MIPs for 1958–2019.

Practical tips¶

• Atmospheric variables (tas, huss, uas, vas) are at 10 m. Do not feed them to a bulk formula that assumes 2 m temperature; use the Large and Yeager-type bulk formula used to produce JRA55-do and recommended in Tsujino et al. (2018) (bulk_ncar.F90).
• Radiation and precipitation are 3-hourly means, with each year's first value centred on 00–03 UTC on 1 January. Wind, temperature, humidity and pressure are snapshots from 00 UTC, so the two sets of time axes are offset by 1.5 hours.
• Total precipitation is prra + prsn and total freshwater runoff is friver + licalvf. All atmospheric variables except sea level pressure are adjusted to reference observations, so they differ from the original JRA-55 fields.
• Versions before v1.5 contained erroneously (anti-cyclonically) rotating tropical cyclones (northeastern Pacific in 1959, North Atlantic in 1967–1987), fixed from v1.5. Keep this in mind when comparing with runs forced by older versions.

Notices and change history¶

References for your paper¶

Reference papers¶

JRA55-do description paper (the reference MRI asks users to cite) — DOI 10.1016/j.ocemod.2018.07.002

@article{tsujino2018jra55do,
  author  = {Tsujino, Hiroyuki and Urakawa, Shogo and Nakano, Hideyuki and Small, R. Justin and Kim, Who M. and Yeager, Stephen G. and Danabasoglu, Gokhan and Suzuki, Tatsuo and Bamber, Jonathan L. and Bentsen, Mats and B{\"o}ning, Claus W. and Bozec, Alexandra and Chassignet, Eric P. and Curchitser, Enrique and Boeira Dias, Fabio and Durack, Paul J. and Griffies, Stephen M. and Harada, Yayoi and Ilicak, Mehmet and Josey, Simon A. and Kobayashi, Chiaki and Kobayashi, Shinya and Komuro, Yoshiki and Large, William G. and Le Sommer, Julien and Marsland, Simon J. and Masina, Simona and Scheinert, Markus and Tomita, Hiroyuki and Valdivieso, Maria and Yamazaki, Dai},
  title   = {{JRA-55} based surface dataset for driving ocean--sea-ice models ({JRA55-do})},
  journal = {Ocean Modelling},
  volume  = {130},
  pages   = {79--139},
  year    = {2018},
  doi     = {10.1016/j.ocemod.2018.07.002}
}

OMIP-2 evaluation paper (JRA55-do-forced experiments, optional) — DOI 10.5194/gmd-13-3643-2020

Acknowledgements¶

MRI asks studies using JRA55-do to cite Tsujino et al. (2018); also state the version used (e.g. v1.6.0, source_id MRI-JRA55-do-1-6-0) in the text. "Feedback should be directed to the authors of the description paper (Tsujino et al. 2018)", not to the JRA-55 project.

Information on the datasets used in this study was compiled with the help of the Korean Climate Data Navigator (KCDN) (Sim, 2026; https://doi.org/10.5281/zenodo.23300923).

Links¶

• MRI JRA55-do official page
• input4MIPs source landing page — MRI-JRA55-do-1-6-0
• JRA55-do production code (GitHub)
• WCRP presentation — CFORCE, next-generation ocean–sea-ice forcing (PDF)