Figure 10

Fig. 10. Measurements of the CO₂ mole fraction in dry air [xCO₂ (air)] as carried out by laboratories "A" through "E" and "G" during the intercomparison exercise. The black horizontal lines represent the overall mean xCO₂ (air) value (±1 s.d.) calculated from profiles "B" through "E." The red horizontal lines represent the mean xCO₂ (air) value (±1 s.d.) calculated from profiles "B" through "E" only for the period where data from all six systems are available (June 7, 22:30 UTC, to June 13, 12:30 UTC).