If Temperatures Rise, Can Earth's Corals Take the Heat?
Carilli, J., Donner, S.D. and Hartmann, A.C. 2012. Historical temperature variability affects coral response to heat stress. PLoS ONE 7: e34418.
To investigate this issue further, Carilli et al., as they describe it, "collected cores from massive Porites sp. corals in the Gilbert Islands of Kiribati to determine how corals along a natural gradient in temperature variability responded to recent heat stress events," in the course of which activity they "examined changes in coral skeletal growth rates and partial mortality scars (Carilli et al., 2010) to investigate the impact of the bleaching event in 2004 (Donner, 2011) on corals from different temperature variability regimes."
In doing so the three researchers - one each from Australia, Canada and the United States - discovered that the spatial patterns in skeletal growth rates and partial mortality scars found in corals from the central and northern islands suggest that "corals subject to larger year-to-year fluctuations in maximum ocean temperature were more resistant to a 2004 warm-water event," and that "a subsequent 2009 warm event had a disproportionately larger impact on those corals from the island with lower historical heat stress."
In the concluding sentence of their paper's abstract, Carilli et al. say their study indicates that "coral reefs in locations with more frequent warm events may be more resilient to future warming," which suggests that taking a little extra heat every once in a while prepares corals to better deal with less frequent but more extreme heat waves when they inevitably do occur.
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