For those of us living in the Anthropocene, evidence of climate change slaps us in the face on a daily basis (like snow literally hitting me in the face last week during the blizzard). But coral reefs are often far from our minds.
Corals come in a wide range of colors for your viewing pleasure, and this color comes from the algae that live within their tissues in a mutually beneficial, or symbiotic, relationship. The algae gives corals energy, and in return the corals give shelter and nutrients to the algae. When corals get stressed out, though, like when it’s just too damn hot in the water, they expel the algae in a phenomenon called coral bleaching, because the lack of algae turns the corals white. Corals can live for a time without the algae, but they will eventually begin to starve and die.
Coral reefs offer far more to the human race than colorful dives and awesome fish. “Food security, shoreline protection and livelihoods from reef tourism provide the social and economic motivation for saving reefs,” Terry Hughes, the lead author of a paper on coral bleaching that was published last week in Science and one of the world’s leading researchers on coral bleaching, told me in an email.
In the paper published yesterday, “Spatial and temporal patterns of mass bleaching of corals in the Anthropocene,” a group of researchers including Hughes investigated the global frequency of severe coral bleaching events. Severe bleaching is when more than 30 percent of corals are bleached in an area of tens to hundreds of kilometers. As Hughes, one of the world’s leading researchers on coral bleaching, said, “Coral bleaching is the new normal.”