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…
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.
To figure out what ocean acidification might have done in the prehistoric past, 21 researchers from the United States, the United Kingdom, the Netherlands, Germany and Spain reviewed studies of the geological record going back 300 million years, looking for signs of climate disruption…
The events that seemed similar to what is happening now included mass extinctions about 252 million and 201 million years ago, as well as the warming period 56 million years in the past.
The researchers reckoned the 5,000-year hot spell 56 million years ago, likely due to factors like massive volcanism, was the closest parallel to current conditions at any time in the 300 million years.
To detect that, they looked at a layer of brown mud buried under the Southern Ocean off Antarctica. Sandwiched between layers of white plankton fossils, the brown mud indicated an ocean so acidic that the plankton fossils from that particular 5,000-year period dissolved into muck.
During that span, the amount of carbon in the atmosphere doubled and average temperatures rose by 10.8 degrees F (6 degrees C), the researchers said. The oceans became more acidic by about 0.4 unit on the 14-point pH scale over that 5,000-year period…
That is a fast warm-up and a quick acidification, but it is small compared with what has happened on Earth since the start of the industrial revolution some 150 years ago, study author Baerbel Hoenisch of Columbia University’s Lamont-Doherty Earth Observatory said…”Given that the rate of change was an order of magnitude smaller…compared to what we’re doing today, and still there were these big ecosystem changes, that gives us concern for what is going to happen in the future,” Hoenisch said.
The know-nothings who avoid consideration of geologic time vs. human time for industrial pollution will ignore this study as they do all science-based study. Ideology is all they’re concerned about. That – and in some cases – their funding from the same creeps who fund political superpacs for the Republican Party.
Acidification of bodies of water on a large or small scale is a disaster. I worked through the acid rain episodes in the northeastern US that destroyed sport fisheries in mountain lakes across the region. Only regulation of the crap spouting from giant coal-fired power plants put a halt to expansion of the crud. The same kind of people who bankrolled those polluters – continue their holy war against a safer environment today.