Researchers from the National Oceanic & Atmospheric Administration (NOAA), tasked with monitoring the overall health of Pacific coral reefs are sounding an alarm of international proportions to notify the public and government agencies that the Pacific Ocean coral reefs are facing a massive die-off known commonly as "coral bleaching". Publishing their recent study in the journal Nature Geoscience, the researchers are pointing towards warming oceans and dying trade winds for the massive coral bleaching soon to hit these coral reefs, and are naming global climate change as a contributing factor.
Led by marine biologist Diane Thompson, the study primarily analyzed corals off of the coasts of remote Pacific islands, each unique yet each sharing the common cause for dying corals. Known to be keystone species of the sea, for their delicate nature, symbiotic relationships with algae and their sensitivity to water temperatures, the corals indicated to the team that in spite of claims denying globally warming in recent years, that temperatures have been on the rise. And when they spike, so does the death toll of the Pacific reefs.
"When winds weaken, which they inevitably will, warming will soon again accelerate" Thompson says. "The warming brought on by greenhouse gases and the warming linked with this all-natural cycle will soon compound one another."
But it's not just the warming temperatures that are going to play a role in the coral bleaching. The researchers also point towards the trade winds which can greatly alter below-surface water temperatures, even when temperatures above soar. Looking to the element Manganese as a proxy for strength of trade winds, the researchers with the NOAA believe now that the winds are dying down and with them so too will the coral reefs.
A nutrient found in the skeletons of corals, Manganese is often released from coral reefs when powerful bursts of wind stir sediments from the underlying sands beneath the coral reefs. And as a result, allows researchers to analyze the wind patterns by measuring the abundance of Manganese within their skeletons.
What the researchers discovered was that the levels of Manganese are fluctuating, indicating quicker rises in global temperatures, and of their oceans, proving that more coral bleaching may soon be on the rise. The NOAA and Thompson's team believe that weakening of the trade winds could happen within the next decade, and that coupled with increasing surface temperatures attributed to climate change, may bring about the end to many coral reefs.
"We're going to continue to see a pattern of high thermal stress that really follows the same sort of time sequence and movement of the 1998 [massive coral die-off] events" Coordinator for the NOAA's Coral Reef Watch program, Mark Eakin says. "Everything we're seeing now says that same pattern [may] happen again this year."