Oceans’ acidic shift may be fastest in 300 million years

Written by Deborah Zabarenko | Environment Correspondent

The world’s oceans are turning acidic at what could be the fastest pace of any time in the past 300 million years, even more rapidly than during a monster emission of planet-warming carbon 56 million years ago, scientists said on Thursday.

Looking back at that bygone warm period in Earth’s history could offer help in forecasting the impact of human-spurred climate change, researchers said of a review of hundreds of studies of ancient climate records published in the journal Science.

Quickly acidifying seawater eats away at coral reefs, which provide habitat for other animals and plants, and makes it harder for mussels and oysters to form protective shells. It can also interfere with small organisms that feed commercial fish like salmon.

The phenomenon has been a top concern of Jane Lubchenco, the head of the U.S. National Oceanic and Atmospheric Administration, who has conducted demonstrations about acidification during hearings in the U.S. Congress.

Oceans get more acidic when more carbon gets into the atmosphere. In pre-industrial times, that occurred periodically in natural pulses of carbon that also pushed up global temperatures, the scientists wrote.

Human activities, including the burning of fossil fuels, have increased the level of atmospheric carbon to 392 parts per million from about 280 parts per million at the start of the industrial revolution. Carbon dioxide is one of several heat-trapping gases that contribute to global warming.

Read the rest of the article on Reuters.

Shifting spring: Arctic plankton blooming up to 50 days earlier now

By Brian Vastag
Washington Post Staff Writer

A light micrograph of plankton including water fleas (family Daphniidae) (Getty Images/oxford Scientific)

Climate researchers have long warned that the Arctic is particularly vulnerable to global warming. The dramatic shrinking of sea ice in areas circling the North Pole highlights those concerns.

A new report finds that the disappearing ice has apparently triggered another dramatic event – one that could disrupt the entire ecosystem of fish, shellfish, birds, and marine mammals that thrive in the harsh northern climate.

Each summer, an explosion of tiny ocean-dwelling plants and algae, called phytoplankton, anchors the Arctic food web.

But these vital annual blooms of phytoplankton are now peaking up to 50 days earlier than they did just 14 years ago, satellite data show.

“The ice is retreating earlier in the Arctic, and the phytoplankton blooms are also starting earlier,” said study leader Mati Kahru, an oceanographer at the Scripps Institution of Oceanography in San Diego.

Read the rest of the story here.