The third and in many respects the greatest concern in the longer term, is that global change is causing the world’s oceans to become more acidic.  By burning immense amounts of fossil fuels, humans, particularly North Americans, are rapidly increasing the concentration of carbon dioxide (CO2) in the atmosphere (by roughly 30% to date).  A quarter of the CO2 produced by the burning of fossil fuels enters the ocean and reacts with water to form carbonic acid, acidifying the ocean.  We have already lowered the pH of the ocean by about 0.1 unit which makes it more difficult and energetically costly for corals to secrete their calcium carbonate skeleton. 

Prior to The Reef Tank blog, I didn't do much if anything at all on the threats of ocean acidification.  I'm happy to state that as our blog grows to include experts on hot topics outside the aquarium realm (including marine conservation and ocean acidification) I've become more and more educated on the subject.

For instance, I just received word from Lina, the project manager over at the European Project on Ocean Acidification (they run a great blog that recently did an amazing guest post for us) that the Monaco Declaration on Ocean Acidification was released last Friday. More than 150 leading marine scientists from 26 countries have signed the declaration, supported by Prince Albert II of Monaco. The scientists are asking for immediate action by policymakers to reduce CO2 emissions sharply so as to avoid widespread and severe damage to marine ecosystems from ocean acidification.

Looks like we're well on our way to making the marine world a better place!

If you thought you couldn't get enough of ocean acidification since Miriam's post, think again! There's so much more that you just don't know (at least I didn't) and Lina Hansson and Jean-Pierre Gattuso from the EPOCA Project Office in Villefranche-sur-mer, France are on hand to tell us exactly what we need to know to keep our marine organisms and ecosystems safe.  Read on to find out what you can do and make sure to check out the additional links found at the bottom of the page.

Besides global warming, another consequence of man's use of fossil fuels is receiving increased attention from the marine scientific community. Ocean acidification has been referred to as “the other CO2 problem”, a much less known but potentially as dramatic result of the approximately 79 million tons of carbon dioxide (CO2) released into the atmosphere every day, not only as a result of fossil fuel burning but also from deforestation and production of cement. Over the past 250 years, the world's oceans have absorbed about one third of the CO2 released due to anthropogenic activities and thus acting like a sink for atmospheric CO2, playing a key role in moderating climate change. Without this capacity of the oceans, the CO2 content in the atmosphere would have been much higher and global warming and its consequences more dramatic. Whereas the chemical consequences of this CO2 uptake are well understood (decrease in pH and shifts in seawater carbonate chemistry) the biological impacts of ocean acidification are poorly known.

Ocean acidification refers to the ongoing decrease in the pH of the Earth's oceans.  Think the corals in your new reef tank have not been affected? Think again!  Miriam from The Oyster's Garter gives us the lowdown on how to preserve life in our oceans. Here's everything you wanted to know about ocean acidification (but were afraid to ask.)

For more on how to help, check out her blog.

Ocean acidification will make off with your children! It will come after you in the night! It's not safe until its head is mounted on my wall! KILL THE BEAST!

Ooops. Wrong movie. But ocean acidification has received a lot of high-profile attention lately, most notably with an editorial in the New York Times. The claims are flying every which way - ocean acidification will kill all the coral reefs, ocean acidification will make the oceans a barren wasteland of jellyfish, ocean acidification will even level the blood-thirsty Humboldt squid.

So here's your handy guide to ocean acidification, and how it might affect coral reefs in particular. I kept it short and semi-sweet, but if you'd like more details or citations just ask!