Ocean Acidification Calculator

Calculate the impact of atmospheric CO2 on ocean pH, carbonate chemistry, and marine ecosystems.

Atmospheric CO2

Current level: ~420 ppm (2024)

Ocean Conditions

Projection Settings

50 years

pH Scale Reference

Preindustrial OceanpH 8.25
Current AveragepH 8.05-8.10
Coral Stress BeginspH 7.9
Critical for ShellfishpH 7.8

Calculated Ocean pH

8.03
0.22 units below preindustrial

Acidity Change

+67%
Increase in hydrogen ion concentration since preindustrial era

Note: pH is logarithmic. A change of 0.1 pH = 26% change in acidity.

Carbonate Chemistry

1.43
Aragonite Saturation
Coral threshold: 3.0
2.14
Calcite Saturation
Shellfish threshold: 2.5

50-Year Projection

1087
ppm CO2
6.96
Ocean pH
0.01
Aragonite

Timeline Projection

YearCO2pHAragonite
20244208.031.43
20345537.810.53
20446877.600.20
20548207.390.07
20649537.170.03
207410876.960.01

Regional Variation

Tropical Pacific
pH 8.08Ar 1.57
North Atlantic
pH 8.01Ar 1.35
Arctic Ocean
pH 7.93Ar 1.00
Southern Ocean
pH 7.95Ar 1.07
Mediterranean
pH 8.06Ar 1.50

Marine Life Impact

Impact Level: Low
  • Coral reefs: At risk
  • Shellfish: Impaired calcification
  • Pteropods: Shell dissolution risk

Ocean CO2 Absorption

10.0 Gt
CO2 absorbed by oceans annually (~25% of emissions)