Why you should care about ocean acidification

A nice diagram on ocean acidification from the folks at the University of Maryland

It may have felt like a normal Saturday, but on May 4th our planet’s atmosphere officially reached 400 ppm of carbon dioxide (about a year earlier than most models predicted). It is quite a scary record to break, seeing has how CO2 levels have not been this high for 4 million years. Prior to the industrial revolution (and for most of the last 800,000 years, our atmosphere was at 280 ppm). But what does this mean for our planet?

 

There may be some disagreement amongst scientists as to the severity of the effects we will expect to see due to climate change, but the general message is the same – things are going to get worse, not better on our planet. Since the last ice age 10,000 years ago things have been quite stable on this little blue place we call earth. This has allowed for our species to proliferate at an incredible rate, since our reproductive mode takes advantage of stable conditions (very few offspring, but lots of energy invested into each child). Lots of other animals and plants have benefited from our rise to supremacy, through co-evolution; such as cats, dogs, rats, wheat, rice, sugar, corn, etc. We need them, they need us, everybody is happy. Well, everybody except those species which do not benefit from our population explosion, which actually are most of them. . .

 

According to something I read recently (sorry, couldn’t find a citation):
“Since the last ice age extinctions of species has occurred on the scale of about 1 every hundred years. But recently that rate is climbing exponentially. Most of the extinctions in the last 10,000 years have occurred in the last 1,000, most of the ones in the last 1,000 years have occurred in the last 100, and most of the extinctions in the last 100 years have occurred in [you guessed it] the last 10 years”

 

coralsgrowing on Koh Tao

Corals grow by taking our calcium and bicarbonate from the oceans and turning that into skeleton, which is actually a form of carbon sequestration.

But what does any of this have to do with ocean acidification you may be asking? Well, one of the big changes we are causing on our planet relates to the burning of fossil soils, carbon locked up for hundreds of millions years in the Earth’s crust. Today we emit on the order of 22 million tons of CO2 per day. If that was all staying in the atmosphere then our planet would already look like Venus. Luckily there are carbon sinks (vegetation, oceans, and to a very small degree rocks). Now, CO2 going into the sea can do a few different things, some of it will remain as little bubbles of CO2 dissolved in the water, some will be absorbed by algae and plants, and some of it reacts with water to form carbonic acid. Some of it is even turned into limestone rock by the corals and reef organisms.

 

 

Naturally, for as long as we can tell, the oceans have been alkaline (PH about 7.9-8.3), so all animals in the sea have evolved to make their skeletons and structures out of carbonate salts, like the calcium carbonate skeleton of corals. When the oceans are more acidic, then it is not only harder for the animals to make their skeletons, but also the reef itself begins to deteriorate faster (ever mix baking soda and vinegar?)

 

 

Coral spawning - Shin Arunrugstichai 2013

Corals, and many other marine organisms are most susceptible in their larvae stage, like these eggs being realsed from a coral in a mass spawning event

Scientists have long stated that 350 ppm is the upper limit for healthy coral reefs, and at 400 ppm we have greatly exceeded that limit. And things show no sign of slowing down yet. Sometimes breaking records is not a good thing. Corals reefs are being hit by many problems worldwide, and this may be the straw that breaks the camel’s back. But its not just about corals, ocean acidification affects all the animals in the sea, from the smallest diatoms and rotifers to the largest animal to ever live on earth, the Blue Whale.

 

You don’t have to be a SCUBA diver to appreciate this loss. This is affecting the food we eat, the air we breathe, and the land we are standing on (in SE Asia, 60% of humans live along the coasts, much of that is protected by reefs).

 

I suspect most people are not aware of these facts or their implications for ours and the rest of the species sharing this planet. Please take a moment to inform your friends and colleagues, and give a little thought each day on how you can reduce your use of fossil fuels. Every one of us in the developed world can easily reduce our consumption by a lot, without making drastic changes in our way of life.

 

It is amazing what our species can do without even realizing it, but it is more amazing what our species can do when we put our minds to it! Don’t give up hope, there are many answers out there, but we actually have to act on the knowledge we receive. Good ideas are worth nothing if they are not followed by action. Get involved in your area, or come help us protect ours. You didn’t end up on this page because you are ignorant to the world’s problems, you made it this far in this article because you care, thank you. Keep up the good work!

 

Susceptible