The other CO2 problem: Tiny planktonic molluscs called pteropods are likely to be impacted by increasing acidity in the Southern Ocean. These organisms are an important component of the food chain, but may be find it difficult to form shells by 2030.
Credit: SPL
SYDNEY: Southern Ocean marine life may start to dissolve away, say Australian scientists, who have discovered that a dangerous 'tipping point' for ocean acidification could arrive as soon as 2030.
This is worrying news, say the experts, because organisms with calcium carbonate skeletons and shells – such as corals, pteropods, krill and other shellfish – may not be able to survive the changing water conditions.
"Our new results point to irreversible and detrimental impacts to Southern Ocean marine calcifying organisms if atmospheric carbon dioxide exceeds 450 ppm [parts per million]," said Ben McNeil, who led the team from the University of New South Wales and government research agency the CSIRO.
Tipping point
Previous work had suggested that the tipping point wouldn't occur until atmospheric carbon dioxide (CO2) passes a concentration of 550ppm, which some climate models predict will be happen by 2060. The revised estimate is published this week in the U.S. journal, the Proceedings of the National Academy of Sciences.
Every year the ocean provides a useful service by absorbing one-third of the 30 billion tonnes of CO2 emitted into the atmosphere by burning fossil fuels.
However, researchers have shown that this dissolved CO2 creates a weak solution of carbonic acid, which is fundamentally changing the chemistry of the marine environment, with significant consequences for many marine plants and animals.
Most affected are animals that use calcium carbonate to build their skeletons. As the ocean becomes mildly more acidic (only a very slightly lower pH, still less acidic than the human body), these animals will find it more difficult to grow. Eventually, at the predicted 'tipping point', research suggests that they may start to find their skeletons and shells dissolve away.
First signs
"It is likely that marine organisms which use calcium carbonate to form skeletons will be among the first to be affected by ocean acidification, especially in colder waters where calcium carbonate is naturally found in lower concentrations," commented Bayden Russell, a marine biologist at the University of Adelaide, South Australia, who was not involved in the study.
Study authors McNeil and Richard Matear, a climate modeller with the CSIRO in Hobart, Tasmania, made their prediction of a revised date for the tipping point by comparing changes to carbonate chemistry in the Southern Ocean over time and across seasons.
Currently levels of CO2 in the atmosphere are estimated at 385 ppm, and levels there are in equilibrium with the amount that dissolves into the seas. If the atmospheric level reaches 450 ppm, though, the ability of microscopic plankton to retain their calcium carbonate shells will be severely affected, said McNeil.
Ocean demise is preventable
This report is fatally flawed in under estimating the lethality of the dose of CO2 already emitted during the past century. CO2 has a lifetime of more than 100 years before it is ultimately dissolved into the surface ocean where it bonds to H2O making H2CO3 (carbonic acid). The amount in the air and sea already will produce the acidification apocalypse regardless of whether we all screw yet another energy efficient light bulb into place. What is needed to compete with the acid forming process Mother Nature has provided and that is the power of ocean photosynthesis in the ocean planktos. Tragically the ocean plants are at a low ebb suffering first and foremost from the onslaught of fossil CO2. The N. Atlantic has lost 17% of its plant life since we gained the satellite technology in the early eighties to measure it, the N. Pacific has lost 26%, and in the Journal Science last year the sub-tropical tropical Pacific was reported to be down by 50%.
With a determined effort of ocean eco-restoration by replenishing diminished mineral micronutrients which used to come from dust in the wind we might just bring ocean plant life back to the levels of 30 years ago when those greener seas annually fixed 4-5 billion tonnes of CO2 into plant life instead of acid death. Here at Planktos-Science.com we are working to restore ocean health by using natural minerals, the most affordable and immediate possible cure for ocean demise. In the bargain the ocean food chain and fisheries will be restored and climate changing and ocean acidifying CO2 will be neutralized.
Don't think for a moment that conservation of preservation will save the oceans and life as we know it on this planet. We must act intelligently and decisively to safe Planet Ocean. By the measure of this report we have barely two decades to succeed.
For more information visit planktos-science.com