GCOS Implementation Plan - WMO

Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC
(2010 Update)
Action O16 [IP-04 O19]
Action: Implement a wave measurement component as part of the Surface Reference Mooring
Network.
Who: Parties operating moorings, coordinated through the JCOMM Expert Team on Waves and
Surges.
Time-Frame: Deployed by 2014.
Performance Indicator: Sea state measurement in the International Data Centres.
Annual Cost Implications: 1-10M US$ (Mainly by Annex-I Parties).
ECV – Surface Current
The global surface current field is primarily relevant to climate through its role in the heat, freshwater
and carbon transport, and the shallow overturning ocean circulation. Research also suggests a role in
determining air-sea exchanges of momentum (wind stress). Derived analyses of the global surface
current field, based primarily on dynamical models, surface wind and sea-level data, are feasible.
Contributing networks and satellite observations include:
• Drifting buoys.
• Global tropical moored buoy network.
• Ship drift.
• Satellite AVHRR (pattern tracking).
• Satellite altimetry (geostrophic).
• Analysis – blended estimates.
• Assimilation (indirect) as in GODAE.
Issues relative to surface current observation and analysis include:
• The in situ and shore-based networks do not provide global coverage or sampling relative to the
required space and time scales.
• Drifting buoys have uneven drift characteristics (drogues) and no agreed standard.
• There is no designated centre for current data exchange, product assembly, quality control and
archiving, or other group performing these functions in research mode.
• Indirect estimates, including those with models (e.g., by GODAE), are data limited and subject to
model biases. Lack of validation data limits ability to estimate uncertainties. However, such
approaches provide the only long-term viable approach.
To address the issues raised above, it is proposed that OOPC work with JCOMM and WCRP to
identify a group of persons and/or organizations willing to establish a programme to collect surface
drifting buoy motions, ship drift current estimates and to make global estimates of current based on
wind stress and surface topography fields.
Action O17 80 [IP-04 O20]
Action: Establish an international group to assemble surface drifting buoy motion data, ship drift
current estimates, current estimates based on wind stress and surface topography fields; prepare
an integrated analysis of the surface current field.
Who: OOPC will work with JCOMM and WCRP.
Time-Frame: 2014.
Performance Indicator: Number of global current fields available routinely.
Annual Cost Implications: