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Over the years, a number of researchers have postulated that many of Earth’s corals are destined to die, with some species even facing extinction, because of the hypothesized connection between the ongoing rise in the air’s CO2 content and reduced rates of coral calcification (Buddemeier, 1994; Buddemeier and Fautin, 1996a,b; Gattuso et al., 1998; Buddemeier, 2001). Kleypas et al. (1999), for example, calculated calcification rates of tropical corals should already have declined by 6 to 11% or more since 1880, as a result of the concomitant increase in atmospheric CO2 concentration; and they predict reductions could reach 17 to 35% by 2100, as a result of expected increases in the air’s CO2 content over the coming century. Likewise, Langdon et al. (2000) calculated a decrease in coral calcification rate of up to 40% between 1880 and 2065.