Role of WCC-SF₆

The World Calibration Centre for Sulfur hexafluoride (WCC-SF₆) is a core facility within the World Meteorological Organization (WMO)/ Global Atmosphere Watch (GAW) programme, responsible for ensuring traceability, calibration, and quality assurance for global SF₆ measurement. Established in October 2012, WCC-SF₆ plays a critical role in maintaining high-quality observational data essential for climate research and policy.

Key responsibilities:

• Ensuring traceability - Linking SF₆ observations from WMO/GAW stations to the WMO/GAW Reference Scale
• Maintaining calibration standards - Providing laboratory and transfer SF₆ gas standards traceable to primary standards
• Conducting inter-comparisons - Organizing regional and global inter-comparison campaigns for WMO/GAW stations and laboratories
• Performing audits & technical support – Ensuring that WMO/GAW stations meet quality control standards through system and performance audits
• Capacity building & training – Providing hands-on training, guidance, and workshops to enhance gloval SF₆ monitoring capabilities
• Public engagement - Sharing updates through reports, websites, and newsletters

WCC-SF₆ in the WMO/GAW Quality Assurance System

WCC-SF₆ operates as part of the WMO/GAW Quality Assurance framework, ensuring that SF₆ measurements across the global monitoring network are consistent and traceable.

• Central Calibration Laboratory (CCL, NOAA/GML) – Maintains the WMO/GAW Reference Scale for SF₆. WCC-SF₆ regularly compares calibration standards with CCL to verify traceability and long-term stability
• GAW Stations – WCC-SF₆ provides calibration support, audits, and training to ensure stations produce high-quality SF₆ data
• World Data Centre for Greenhouse Gases (WDCGG, JMA) – WCC-SF₆ ensures and supports that data reported by stations meets quality standards
• GAW Scientific Advisory Groups & QA/SACs – WCC-SF₆ works with these groups to develop best practices for measurement quality control

How WCC-SF₆ Supports GAW Stations

• Maintains traceability by linking station measurements to the WMO/GAW Reference Scale
• Performs regular inter-comparisons to assess and improve measurement consistency
• Conducts audits & technical support to help stations identify and resolve measurement issues
• Provides training to enhance regional SF₆ measurement capabilities

Through these activities, WCC-SF₆ ensures that SF₆ observations worldwide remain accurate, reliable, and scientifically robust, supporting climate research and international greenhouse gas monitoring efforts.

Elements of the Quality Assurance system, QA activities and workflow in GAW (Reconstructed based on WMO/GAW report No. 228)

Relevant reports and documents