Objective

The aims of COWCLIP are to raise the profile of wind-waves as a variable in the global climate system – both to foster and support determination of:

  • the effects of climate variability and change on the wave climate, and
  • the feedback influences of waves on the coupled ocean-atmosphere climate system.

Goals of COWCLIP are:

  1. Establish a collaborative working group with interest in global wave climate historical and future variability and change
  2. Resolve priority questions to aid climate impacts community
  3. Document wave climate projections methods being applied, and summarise existing wave climate projection studies
  4. Define a working protocol for wave climate projections:
    1. Agreed standard inter-comparison experiments to obtain adequate coverage of sampling space, to establish variance associated with several layers of uncertainty
    2. Minimum set of analyses/validation requires to foster inter-comparisons (projections and coupled models independently)
  5. Develop a technical framework to support the working group
    1. Project data server, QC, standard variables, etc

Future 21st Century changes in wind-wave climate have broad planning implications for coastal and offshore ecosystems and infrastructure. Atmosphere-ocean general circulation models (GCM) are now routinely used for assessing and providing future projections of climatological parameters such as temperature and precipitation, but generally these provide no information on ocean wind-waves. To fill this information gap a growing number of studies are using GCM outputs and independently producing global and regional scale wind-wave climate projections. To consolidate these efforts, understand the sources of variance between projections generated by different groups, and ultimately provide a robust picture of projected changes, we present strategies from the community derived multi-model ensemble of wave climate projections (COWCLIP) and an overview of regional contributions. The objective of COWCLIP is to make community based ensembles of wave climate projections freely accessible to the scientific community, to provide the necessary information to support comprehensive coastal impacts of climate change studies.

Results of COWCLIP provided the foundation for the assessment of wind-wave climate variability and change within the Intergovernmental Panel for Climate Change (IPCC) Working Group 1 Fifth Assessment Report (AR5). In this report – the first assessment to include assessment of waves – changes in wave climate were projected over the 21st Century, with high uncertainty. The most robust feature of change identified in the assessment being a projected increase in wave heights in the Southern Ocean in future scenarios.