The Joint WMO-IOC Technical Commission for Oceanography and Marine Meteorology

Coordinated Ocean Wave Climate Project (COWCLIP)


Surface wind waves were identified in the Intergovernmental Panel for Climate Change (IPCC) Fourth Assessment Report (AR4) as one of the key drivers in the coastal zone, but little information was available on projected changes under future climate scenarios. The main focus was on the influence of sea-level rise and inundation effects. The IPCC Working Group II recognised that risks to coastal population and ecosystems require inclusion of a broader range of coastal drivers of change. One of the key drivers, which has received insufficient attention to date, is wind-waves.


The Coordinated Ocean Wave Climate Project (COWCLIP) aims to generate wave climate projections (ultimately of global extent) and aid comprehensive assessments of their cascading uncertainty by:

  • Providing a systematic, community-based framework and infrastructure to support validation, intercomparison, documentation and data access for wave climate projections forced from CMIP5 datasets;
  • To describe best practice for regional wave climate projections, and ;
  • Engaging interests of the wave community into the wider climate community and ultimately developing coupled wind-wave Atmosphere-Ocean global climate models to support quantification of wind-wave driven feedback in the coupled climate system.



-          COWCLIP wiki site (hosted by CSIRO)                                                                                                                                                                                            


COWCLIP NEWS (29-Jan-2013)

  1. COWCLIP workshop/review meeting, Oct-Nov, 2013
  2. COWCLIP Phase 2 invitation
  3. COWCLIP Phase 1 complete


COWCLIP review meeting (Nov. 2013)


First Announcement of COWCLIP Review meeting, and call for abstracts for COWCLIP session at the 2013 Wave Workshop. 

An open invitation COWCLIP review meeting is scheduled to align with the 13th International Workshop on Wave Hindcasting and Forecasting ( 

A COWCLIP related wave climate session is proposed for the Wave Workshop, and we invite abstracts across the following themes for this session:
a. Historical wave climate variability and change
b. Regional and global wind-wave climate projections
c. The role of wind-waves in the coupled climate system.
Please submit abstracts to the conference organisers and advise that it is associated with the COWCLIP meeting.

The objectives of the COWCLIP review meeting are to:
- Assess progress of the COWCLIP project against the objectives agreed at the Geneva workshop (see
- Review future activities for COWCLIP

Please contact This email address is being protected from spambots. You need JavaScript enabled to view it. if you plan to attend the review meeting.

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COWCLIP Phase 2 (ongoing until Nov. 2013)

We would like to invite all to contribute to the COWCLIP Phase 2 intercomparison study. 

The phase 1 dataset had considerable limitations in quantifying the source of variance between available studies as the ensemble spanned difference emission scenarios, using different GCM's, RCM's, wave model and downscaling approaches.
The primary objective of phase 2 is to overcome these limitations with a more designed approach, using CMIP5 derived datasets.

If you are prepared to contribute your data to this study, could you please send the following details for each ensemble run for which you have global wave projections available. Note the following details are obtained from the CMIP5 ESG data portal pages.
1. GCM (e.g., HadGEM2-ES etc)
2. Historical Experiment (e.g., Historical)
3. Historical Ensemble (e.g., r1i1p1)
4. Historical time-slice (e.g., 1979-2005)
5. Projected Future Experiment (e.g., rcp45)
6. Projected Future Ensemble (e.g., r1i1p1)
7. Projected Future time-slice (e.g., 2080-2100)
8. Forcing variables and frequency (e.g., 3 hourly uas and vas)

Once these details are available from all contributors, we will identify which GCM forcing ensemble(s) have the most available wave projection datasets, summarise details here in this spreadsheet, and ask you to contribute data for those runs to the intercomparison study.

We hope to make good progress on the phase 2 intercomparison before the COWCLIP review meeting scheduled for late October 2013 (see below). For this reason, we ask you to please provide these details to This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. by Feb 17, 2013.

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COWCLIP Phase 1 complete (Nov. 2011)

A manuscript, published in Nature Climate Change, detailing inter-comparison of the first community ensemble of global wave climate projections is now available online. This completes phase 1 of COWCLIP, which had the objective of comparing studies which were available or underway at the time of the first COWCLIP workshop in Geneva (April, 2011).

The manuscript:
Hemer, M.A., Y. Fan, N. Mori, A. Semedo and X.L. Wang, Projected Changes in wave climate from a multi-model ensemble, Nature Climate Change, DOI: 10.1038/nclimate1791
Can now be accessed online at:

This follows other COWCLIP related manuscripts:
Hemer, M.A., X.L. Wang, J.A. Church and V.R. Swail (2010) Coordinated global ocean wave projections. Bull. Amer. Meteor. Soc., 91(4), 451-454. DOI: 10.1175/2009BAMS2951.1.
Hemer, M.A., X.L. Wang, R. Weisse, and V.R. Swail (2012) Community advancing wind-waves climate science: The COWCLIP project. Bulletin of the American Meteorological Society, 93(6), 791-796. doi: 10.1175/BAMS-D-11-00184.1
Cavaleri, L., B. Fox-Kemper and M.Hemer (2012) Wind-waves in the coupled climate system. Bulletin of the American Meteorological Society. 93(11), 1651-1661. DOI: 10.1175/BAMS-D-11-00170.1

COWCLIP phase 1 projections datasets (NetCDF format) are available here.


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