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Natural variations in ocean pH both in time and space dwarf human-induced trends.

Pertinent to my recent response to New Scientist on ocean
acidification, Willis Eschenbach has a fascinating piece at Wattsupwiththat on a study of ocean pH along a transect from Hawaii
to Alaska. Turns out that the further north you go, the less
alkaline the ocean:

As one goes from Hawaii to Alaska
the pH slowly decreases along the transect, dropping from 8.05 all
the way down to 7.65. This is a change in pH of almost half a

The study also measured the change caused by carbon dioxide from

The maximum anthropogenic change
[at the surface] over the entire transect was -0.03 pH in fifteen
years. The average anthropogenic change over the top 150 metre
depth was -0.023. From there down to 800 metres the average
anthropogenic change was -0.011 in fifteen years.

In other words,

That means that at the current
rate of change, the surface water in Hawaii will be as alkaline as
the current Alaskan surface water in … well … um … lessee, divide
by eleventeen, carry the quadratic resdual … I get a figure of 566
years. But of course, that is assuming that there would not be any
mixing of the water during that half-millennium.

Eschenbach coincidentally uses much the same words as I did
about ocean acidification:

My conclusion? To mis-quote Mark
Twain, “The reports of the ocean’s death have been greatly

One of Eschenbach’s readers then points out (don’t you love the
way information can meet on the web?) that the pH of the water
entering the Monterey Bay aquarium has been measured for many years

the sea creatures in the Monterey
Bay can easily withstand a change in pH of 0.5 in the course of a
single month


By Matt Ridley | Tagged:  general