The accelerating acidification of oceans could have potentially disastrous, widespread effects on marine ecosystems within decades. The results might bear considerable consequences for humankind as well. Only swift action to curb greenhouse gas emissions can address the threat successfully. These are the warnings from 155 marine scientists from 26 countries who signed the Monaco Declaration, released January 30, 2009. The declaration summarizes results from an October 2008 symposium on the subject, sponsored by the UN Educational, Scientific, and Cultural Organization and other intergovernmental organizations.
Atmospheric concentrations of CO2—now about 385 parts per million (ppm)—have climbed up to 38% over preindustrial levels, with half of that increase taking place during the past 30 years, the declaration notes. Oceans absorb the CO2 and become more acidic, and ocean acidification reduces the availability of carbonate ions used by myriad marine species in constructing shells and skeletons. Data from key marine regions reveal the increasing occurrence of lighter-weight animal shells and slower coral reef formation. Holding CO2 levels below about 550 ppm will require reversing the current increase in emissions of 3% per year by 2020, the scientists say. However, studies indicate that even at 450 ppm of atmospheric CO2, corrosion of reefs will outpace their growth, making them largely unsustainable, and the intensifying acidity of polar waters will dissolve the shells of animals important to marine food chains. The repercussions on fisheries would imperil food sources for millions of people. Even steeper reductions in emissions will be required to prevent this from happening, the declaration says.
I may have to re-think that decision to call this unfolding mess “climate chaos”. That suddenly seems to be far too mild a phrase.
Lou Grinzo, the energu collective, 5 March 2009. Article.
