By David L. Brown
The bad news just keeps coming about our environment. Just yesterday I reported on new evidence of ice melting in Antarctica. Now Reuters reports on a paper in the journal Science which reveals that the Southern Ocean which surrounds that ice-bound continent is saturated with carbon dioxide and cannot be relied upon to absorb much if any more.
That’s bad news because the frigid waters represent 15 percent of the oceanic sink which was being counted on to absorb human-produced CO2. Science has not yet posted the current issue on its web site. Here are details from the Reuters story:
WASHINGTON (Reuters) — The Southern Ocean around Antarctica is so loaded with carbon dioxide that it can barely absorb any more, so more of the gas will stay in the atmosphere to warm up the planet, scientists reported Thursday.
Human activity is the main culprit, said researcher Corinne Le Quere, who called the finding very alarming.
The phenomenon wasn’t expected to be apparent for decades, Le Quere said in a telephone interview from the University of East Anglia in Britain.
“We thought we would be able to detect these only the second half of this century, say 2050 or so,” she said. But data from 1981 through 2004 show the sink is already full of carbon dioxide. “So I find this really quite alarming.”
The Southern Ocean is one of the world’s biggest reservoirs of carbon, known as a carbon sink. When carbon is in a sink — whether it’s an ocean or a forest, both of which can lock up carbon dioxide — it stays out of the atmosphere and does not contribute to global warming.
Increased winds over the last half-century are to blame for the change, Le Quere said. These winds blend the carbon dioxide throughout the Southern Ocean, mixing the naturally occurring carbon that usually stays deep down with the human-caused carbon.
When natural carbon is brought up to the surface by the winds, it is harder for the Southern Ocean to accommodate more human-generated carbon, which comes from factories, coal-fired power plants and petroleum-powered motor vehicle exhaust.
The winds themselves are caused by two separate human factors.
First, the human-spawned ozone depletion in the upper atmosphere over the Southern Ocean has created large changes in temperature throughout the atmosphere, Le Quere said.
Second, the uneven nature of global warming has produced higher temperatures in the northern parts of the world than in the south, which has also made the winds accelerate in the Southern Ocean.
“Since the beginning of the industrial revolution the world’s oceans have absorbed about a quarter of the 500 gigatons of carbon emitted into the atmosphere by humans,” Chris Rapley of the British Antarctic Survey said in a statement.
“The possibility that in a warmer world the Southern Ocean — the strongest ocean sink — is weakening is a cause for concern,” Rapley said.
There just doesn’t seem to be an end to the rolling thunder of bad news about the environment. Meanwhile, our politicians blather about all manner of insignificant issues and personal attacks, the popular press obsesses over Hollywood non-entities, and the masses continue on as if nothing will ever change. It appears ever clearer that we are on the downward slide into some very dangerous times, with tipping points and feedback effects combining to change our world in ways that we cannot understand that which may bring an end to our civilization.