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Predominance diagrams

Speciation plots

Reaction path calculations

Fitting

Contouring


Weekly average CO2 at Mauna Loa

Sept 13, 2026
425.91 ppm
1 year ago
424.04 ppm
10 years ago
401.60 ppm
Pre-industrial
270 ppm
Year-on-year change
1.87 ppm

When will the Year-on-year increase come down to zero, or at least show a definite downturn? At the moment, it appears to be still on an upward trend! The reason is pretty clear.