World Calibration Centre (WCC-Empa) for Surface Ozone, Carbon Monoxide, Methane, Carbon Dioxide and Nitrous Oxide
WCC-Empa was established in 1996, assuming worldwide responsibility for surface ozone, carbon monoxide and methane comparisons at global GAW stations. WCC-Empa was also mandated to extend its activities to carbon dioxide in 2010 and nitrous oxide in 2025.
The goals of the WCC-Empa are
- To ensure that measurements are fully traceable to the designated GAW reference
- To assist stations with regards to instrument and/or measurement problems
- To improve technical know-how at stations through on-site training
through
- Regular system and performance audits at global GAW stations including inter-comparison measurements with traveling standards.
- Maintaining laboratory and traveling standards for surface ozone, carbon monoxide, methane and carbon dioxide.
- Ensuring traceability of the WCC-Empa laboratory standards trough regular inter-comparisons with the corresponding GAW Central Calibration Laboratories.
WCC-Empa measurements are traceable to
- NIST Standard Reference Photometer SRP#2 (surface ozone)
- NOAA/GML WMO-X2014A carbon monoxide scale
- NOAA/GML WMO-X2004A methane scale
- NOAA/GML WMO-X2019 carbon dioxide scale
- NOAA/GML WMO-X2006A nitrous oxide scale
Achievements
Benefits of WCC-Empa audits include
- Improved data quality
- Increased data availability
- Improved technical know-how of station operators
- Increased awareness and acceptance of the GAW programme
WCC-Empa Audits
- Alert - 2004
- Amsterdam Island - 2008
- Anmyeon-do - 2014, 2017, 2022
- Arembepe - 2001
- Assekrem - 2003, 2007, 2015
- Baring Head - 2023
- Barrow - 2008
- Bukit Kototabang - 1999, 2001, 2004, 2007, 2008, 2011, 2014, 2019, 2024
- Cape Point - 1997, 1998, 2002, 2006, 2011, 2015, 2021, planned 2025
- Cape Verde - 2012
- Chacaltaya - 2024
- Cholpon Ata - 2023
- Danum Valley - 2008, 2013, 2024
- El Tololo - 2017
- Hohenpeissenberg - 1997, 2006, 2011, 2020
- Izaña - 1996, 1998, 2000, 2004, 2009, 2013, 2019, 2023
- Jeju Gosan - 2017, 2022
- JMA - 2005
- Jungfraujoch - 1999, 2006, 2015, 2021
- Kennaook / Cape Grim - 2002, 2016, 2023
- Lauder - 2010, 2016
- La Réuion - 2022
- Linan - 2016
- Mace Head - 1996, 1998, 2002, 2005, 2009, 2013, 2018
- Mauna Loa - 2003
- Mt. Cimone - 2012, 2018, 2023
- Mt. Kenya - 2000, 2002, 2005, 2006, 2008, 2010, 2015, 2019, 2021
- Mt. Waliguan - 2000, 2004, 2009, 2016
- Pallas - 1997, 2003, 2007, 2012, 2021
- Pha Din - 2022
- Puy de Dôme - 2016
- Regional Calibration Centre for Surface Ozone Buenos Aires - 2010, 2017
- Ryori - 2005
- Sonnblick - 1998, 2020
- Ushuaia - 1998, 2003, 2008, 2016, 2019, planned 2025
- Zeppelin Mt. - 1997, 2001, 2005, 2012, 2022
- Zugspitze / Schneefernerhaus - 1996, 1997, 2001, 2006, 2011, 2020
Further Information
Global Atmosphere Watch: Introduction
WCC-Empa (World Calibration Centre for Surface Ozone, Carbon Monoxide, Methane and Carbon Dioxide)
QA/SAC Switzerland (Quality Assurance/Scientific Activity Centre)
GAW-qc (Interactive quality control tool for atmospheric composition measurements)
GAWSIS (GAW Station Information System)
WMO Report No. 1215: An Update on Low-cost Sensors for the Measurement of Atmospheric Composition, December 2020
WMO Report No. 1215: Low-cost sensors for the measurement of atmospheric composition: overview of topic and future applications (2018)
GAW Report No. 292: Twenty-first WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases and Related Measurement Techniques (GGMT-2022)
GAW Report No. 255: 20th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases and Related Measurement Techniques (GGMT-2019)
GAW Report No. 242: 19th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases and Related Measurement Techniques (GGMT-2017)
GAW Report No. 229: 18th WMO/IAEA Meeting on Carbon Dioxide, Other Greenhouse Gases and Related Measurement Techniques (GGMT-2015)
GAW Report No. 209: Guidelines for Continuous Measurements of Ozone in the Troposphere
GAW Report No. 192: Guidelines for the Measurement of Atmospheric Carbon Monoxide