In a study published Wednesday in the journal PLOS ONE, a group of scientists from various state and federal agencies, universities and bird rescue organizations documented the die-off and concluded from the data that it was caused by a record-breaking ocean heat wave in 2014 through 2016 that triggered systemic changes throughout the ocean ecosystem.
What we commonly see accumulating at the sea surface is “less than the tip of the iceberg, maybe a half of 1% of the total,” says Erik Van Sebille, an oceanographer at Utrecht University in the Netherlands.
The ocean absorbs carbon dioxide from the atmosphere, which reduces pH levels and concentrations of calcium carbonate, a mineral used by shellfish to calcify their shells. As more carbon is released into the atmosphere, concentrations of calcium carbonate decrease and the shells of organisms like foraminifera get thinner, a trend Osborne saw clearly in the sediment cores she examined.
“The shell thickness record instantly showed a long-term declining trend,” she said. “It was really obvious across entire record.”
This loss of oxygen in the ocean is significant enough to affect the planetary cycling of elements such as nitrogen and phosphorous which are, “essential for life on Earth,” Dr. Laffoley said.
As the amount of atmospheric carbon dioxide continues to rise, our oceans are playing an increasingly important role in absorbing some of this excess. In fact, it was reported recently that the global ocean annually draws down about a third… Read More ›