launched their own studies. These, too, confirmed Langdon’s discovery:
reef-building corals are sensitive to the saturation state. This has now
been shown in dozens more lab studies and also on an actual reef. A few
years ago, Langdon and some colleagues conducted an experiment on a
stretch of reef near a volcanic vent system off Papua New Guinea. The
experiment, modeled on Hall-Spencer’s work at Castello Aragonese, again
used the volcanic vents as a natural source of acidification. As the
saturation state of the water dropped, coral diversity plunged. Coralline
algae declined even more drastically, an ominous sign since coralline algae
act like a kind of reef glue, cementing the structure together. Seagrass,
meanwhile, thrived.
“A few decades ago I, myself, would have thought it ridiculous to
imagine that reefs might have a limited lifespan,” J. E. N. Veron, former
chief scientist of the Australian Institute of Marine Science, has written.
“Yet here I am today, humbled to have spent the most productive
scientific years of my life around the rich wonders of the underwater
world, and utterly convinced that they will not be there for our children’s
children to enjoy.” A recent study by a team of Australian researchers
found that coral cover in the Great Barrier Reef has declined by fifty
percent just in the last thirty years.
Not long before their trip to One Tree, Caldeira and some of the other
members of his team published a paper assessing the future of corals,
using both computer models and data gathered in the field. The paper
concluded that if current emissions trends continue, within the next fifty
years or so “all coral reefs will cease to grow and start to dissolve.”
IN between trips out over the reef to collect samples, the scientists at
One Tree did a lot of snorkeling. The group’s preferred spot was about a
half a mile offshore, on the opposite side of the island from DK-13, and
getting there meant cajoling Graham, the station manager, into taking
out the boat, something that he did only with reluctance and a fair
amount of grumbling.