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Predominance diagrams

Speciation plots

Reaction path calculations

Fitting

Contouring


Weekly average CO2 at Mauna Loa

Sept 27, 2026
425.68 ppm
1 year ago
-999.99 ppm
10 years ago
400.96 ppm
Pre-industrial
270 ppm
Year-on-year change
1425.67 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.