Warming could hurt Alaska coral

Two decades ago, scientists didn’t know coral reefs existed in the cold, deep seas off Alaska. Those reefs may now be among the first victims of global warming in a marine environment that’s home to half of the U.S.’s commercial fishing, researchers said Tuesday.

The loss of Alaska’s cold-water reefs may be a precursor to the extinction of reefs worldwide that’s expected to occur by the end of the 21st century because of acidification, which occurs when oceans absorb carbon dioxide, according to Oceana, a Washington-based conservation group.

Alaska’s cold water absorbs more of the atmosphere’s increasing carbon dioxide than tropical waters do. The resulting acidification prevents marine life such as coral, crabs, lobsters and oysters from building calcium carbonate skeletons and shells, impairing their ability to survive and reproduce.