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"First and foremost is the fact that calcification cannot be accurately modeled on a purely physical-chemical basis that is readily amenable to mathematical representation, for it is a biologically-driven physical-chemical process that behaves much differently than has been implied by the simplistic "lifeless" analyses of the researchers cited above, as has been repeatedly demonstrated by many of the studies we have reviewed and archived under the heading of Calcification in our Subject Index.....Second, and the subject of this Editorial, is the fact that marine photosynthesis tends to increase surface oceanic pH, countering the tendency for it to decline as the air's CO2 content rises, as has been demonstrated by Lindholm and Nummelin (1999). This phenomenon has been shown to have the ability to dramatically increase the pH of marine bays, lagoons and tidal pools (Gnaiger et al., 1978; Santhanam, 1994; Macedo et al., 2001; Hansen, 2002), as well as significantly enhance the surface water pH of areas as large as the North Sea (Brussaard et al., 1996). And to this sizable body of research can now be added the findings of Middelboe and Hansen (2007), who studied a wave-exposed boulder reef in Aalsgaarde on the northern coast of Zealand, Denmark, and a sheltered shallow-water area in Kildebakkerne in the estuary Roskilde Fjord, Denmark."....."Adding to these findings the fact that rising atmospheric CO2 concentrations tend to stimulate marine photosynthesis, it can be appreciated that doom-and-gloom stories of impending extinctions of earth's marine calcifying organisms due to a CO2-induced decrease in oceanic pH are merely that - stories, without any basis in fact."