A pH of 7 is neutral, a pH less than 7 is acidic, and a pH greater than 7 is basic. Ocean water is normally slightly basic, with a surface-water pH of about 8.2, but that has declined in recent years to about 8.1. A decrease of 0.1 pH units may not seem like much, but because the pH scale is logarithmic, each unit on the pH scale represents a tenfold change in acidity.

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A pH of 7 is neutral, a pH less than 7 is acidic, and a pH greater than 7 is basic. Ocean water is normally slightly basic, with a surface-water pH of about 8.2, but that has declined in recent years to about 8.1. A decrease of 0.1 pH units may not seem like much, but because the pH scale is logarithmic, each unit on the pH scale represents a tenfold change in acidity.

A pH of 7 is neutral, a pH less than 7 is acidic, and a pH greater than 7 is basic. Ocean water is normally slightly basic, with a surface-water pH of about 8.2, but that has declined in recent years to about 8.1. A decrease of 0.1 pH units may not seem like much, but because the pH scale is logarithmic, each unit on the pH scale represents a tenfold change in acidity.