New Zealand plankton blooms proof of global warming's oceanic effects

"It is clear that change is underway," said researcher Lionel Carter.
Brooks Hays UPI Yahoo News 17 Oct 16;

WELLINGTON, New Zealand, Oct. 17 (UPI) -- During coccolithophore blooms, the algae's calcium-derived exoskeletons turn the ocean water a milky white. The microorganism's proliferation can often be seen from space.

Satellites passing over New Zealand in recent months have documented a series of coccolithophore blooms off the island nation's east coast. According to a new study published in the journal Global and Planetary Change, coccolithophore blooms and the microfossils they leave behind offer evidence of global warming's oceanic effects.

The tiny calcified scales left behind by the algae are called coccoliths. In addition to forming world famous coastlines, like England's White Cliffs of Dover, the microfossils can also help scientists study ancient oceanic conditions.

Researchers from Victoria University of Wellington used coccoliths, as well as ship and satellite observations, to map the movement of modern and ancient coccolithophore blooms.

The latest data suggest blooms are moving southward as the ocean warms and seas calm. Coccolith deposits revealed similar patterns from 130,000 years ago, when global ocean temperatures last rose.

"Our results show that during that last warm period, when the ocean was about one to two degrees warmer than present, sediments on the seabed were mainly made up of coccoliths," researcher Bella Duncan explained in a news release.

Researchers say a similar warming period encouraged the proliferation of coccolithophores that ultimately birthed the White Cliffs of Dover.

"While the ramifications of this change on fish stocks, uptake of carbon dioxide and general ocean health have yet to be evaluated, it is clear that change is underway," said Lionel Carter from Victoria's Antarctic Research Centre.

Scientists hope further exploration of similarities between modern and ancient patterns of climate change will offer insights into the future of Earth's warming oceans.