Round Robin #6 is currently underway [started: January 2014]

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 and 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).

Parameter(s) Calibration Scale* Primary Contact Lab
CO2 WMO-CO2-X2007 Pieter Tans NOAA
CH4 WMO-CH4-X2004 Ed Dlugokencky NOAA
CO WMO-CO-X2004 Paul Novelli NOAA
N2O WMO-N2O-X2006A Brad Hall NOAA
SF6 WMO-SF6-X2006 Brad Hall NOAA
H2 NOAA-H2-X1996 Paul Novelli NOAA
δ13C and δ18O (CO2) SIL Lab Scale Bruce Vaughn SIL
*If a scale revision occurs at the organizing lab while a Round Robin experiment is underway, comparison results will be relative to the scale in use at the start of the Round Robin.