Round Robin #7 is currently underway [started: November 2020]

Please Note: The current Round Robin experiment will close on 2022-12-31.

Calibration scales of the current WMO/IAEA Round Robin Experiment.

A World Meteorological Organization (WMO) Central Calibration Laboratory (CCL) is responsible for maintaining and distributing the WMO Mole Fraction scale for a specified gas in air. NOAA Earth System Research Laboratory (ESRL) Global Monitoring Division (GMD) is the WMO CCL for CO2, CH4, N2O, SF6, and CO. Max Planck Institute for Biogeochemistry (MPI-BGC) laboratory in Jena, Germany is the CCL for H2 and for the stable isotopes of CO213C and δ18O).

The following table summarizes the calibration scales used to assign values to the current WMO Round Robin cylinders. Please Note: For these experiments, H2 values have been assigned to the WMO Round Robin cylinders by NOAA, the stable isotopes of CO2 values have been assigned by the University of Colorado (CU), Institute of Arctic and Alpine Research (INSTAAR), Stable Isotope Laboratory (SIL), and O2/N2 values have been assigned by the National Center for Atmospheric Research (NCAR).

Parameter(s) Calibration Scale* Primary Contact Lab
CO2 WMO-CO2-X2019 Pieter Tans NOAA
CH4 WMO-CH4-X2004A Ed Dlugokencky NOAA
CO WMO-CO-X2014 Gabreille.Petron NOAA
N2O WMO-N2O-X2006A Brad Hall NOAA
SF6 WMO-SF6-X2014 Brad Hall NOAA
δ13C and δ18O (CO2) SIL Lab Scale Bruce Vaughn SIL
O2/N2 Scripps O2 Scale Britton Stephens (NCAR) SIO