Editor’s note: Marshall Brain – futurist, inventor, NCSU professor, writer and creator of “How Stuff Works” is a contributor to WRAL TechWire.  Brain takes a serious as well as entertaining look at a world of possibilities for Earth and the human race.  He’s also author of “The Doomsday Book: The Science Behind Humanity’s Greatest Threats.” With temperatures in the world’s oceans at record highs, here’s a look back at what Brain wrote about threats to the waters just a year ago. 


RALEIGH – What if I told you that humanity stands on the brink of utterly destroying the world’s oceans? Of destroying all of the coolest ocean species, everything from coral reefs to blue whales? And what if you may have never heard of the process that will bring on all of this death and destruction?

Imagine that we are having a conversation together and I say to you these two words: “Ocean Acidification”. These words might be completely foreign to you. You may have never heard of “ocean acidification” before. But these two words will become extremely important – deadly in fact – to a huge swath of life on planet Earth in the years to come.

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Stepping back

Let’s step back for one moment and think about what is happening to planet Earth right now. It goes like this:

  1. Humans burn fossil fuels. LOTS of fossil fuels. How much? Humanity burns more than a trillion gallons of oil and approximately an equivalent amount of coal every year.
  2. These fossil fuels turn into something like 35 gigatons (70 trillion pounds) of carbon dioxide per year when they burn.
  3. This new carbon dioxide enters the atmosphere. Therefore, the amount of carbon dioxide in the atmosphere has been growing steadily.

PPM, Carbon Dioxide. Image provided by Marshall Brain.

What’s happening

Back in 1750, before humans had really discovered fossil fuels, there were 277 parts per million (PPM) of carbon dioxide in the atmosphere. Then the industrial revolution and modern civilization happened. Today the reading stands around 420 PPM. This number is growing by about 2.4 PPM per year and shows no signs of slowing down. A quick video like this one can help you visualize what is happening.

What does all this new carbon dioxide have to do with the ocean? In a nutshell, some of this new carbon dioxide in the atmosphere gets absorbed by the ocean. And when carbon dioxide mixes with water it creates an acid called carbonic acid. This is what “ocean acidification” is all about. As new carbonic acid forms, the ocean is becoming more and more acidic.

A more acidic ocean

The ocean has absorbed about 30% of all the new carbon dioxide that humans have added to the atmosphere, according to the National Oceanic and Atmospheric Administration (NOAA). It means that the ocean is now much more acidic than it was back in 1750. Is the new acid in the ocean going to melt your hand off if you stick it in the water? No, it’s not like that. The pH of the ocean is more subtle than that, moving from 8.2 to 8.1 over the years, and heading toward 7.8 in the future. This seemingly small change now, and the changes that will inevitably happen in the future, will make our oceans more acidic than they have been for millions of years.

It turns out that a more acidic ocean is a terrible thing for animals living in the ocean, and it may end up being our undoing. Everything living in the ocean evolved with the ocean pH at one level, and now humans have suddenly made the ocean much more acidic.

Impact of more acidic oceans

Any animal that forms a shell is turning calcium in the water into calcium carbonate in its shell. The new acid in the water makes this process more difficult. So the animal has to use up more energy building and repairing its shell, which means it has less energy for growing and reproducing. The shells are also weaker. Ultimately this means less shellfish, smaller shellfish, or dead/extinct shellfish, depending on the species.

So what? Who cares? It means that coral reefs are doomed. They simply will not survive in a more acidic ocean. It means that animals like oysters, mussels, clams, and snails are doomed. They cannot reproduce in more acidic water, and the acid eats at the shells of adults. And so on. This video provides a sobering view of what’s at stake.

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It gets worse

But the terrifying thing is the effect that ocean acidity will have on plankton. Plankton come in two flavors: phytoplankton are plants and zooplankton are animals. Like all plants, the phytoplankton are absorbing sunshine and creating oxygen. The zooplankton eat the phytoplankton. And every other lifeform in the ocean depends in one way or another on these plankton, which are floating freely in the ocean by the quadrillions. There is something like a billion tons of plankton in the ocean at any given time.

Since most plankton are too small to see, humans tend to be oblivious. But it turns out that plankton are incredibly important to us.

Plankton are the bottom level of the entire ocean food chain. Nearly every ocean animal depends on plankton either directly or indirectly. A blue whale, for example, eats 32,000 pounds of plankton every day. If we eliminate plankton, nearly every ocean animal dies.

And the problem is that ocean acidification affects plankton too. And the oceans are also warming. Ocean acidification plus warming can be deadly to many species of plankton. Since so much of all of Earth’s life is found in the ocean, and it all depends on plankton, this could be a gigantic recipe for disaster at a global scale.

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Our role

What can humanity do to avert a planetary catastrophe caused by ocean acidification? We have to do two things quickly:

  1. Humanity must stop burning all fossil fuels
  2. Humanity must start extracting excess carbon dioxide back out of the atmosphere

If humanity does not do this, we are doomed. We will destroy the oceans as described above. We will destroy the rainforests as described in the previous article. We will heat up the planet so much that big swaths of the planet will become uninhabitable, as we will discuss next week. We will melt the ice sheets and raise sea levels, destroying all of the beaches and coastal cities planet-wide.

Given what’s at stake, it is impossible to believe that humanity is doing so little. Fossil fuel use is increasing, not decreasing. Rain forest destruction is increasing, not decreasing. Carbon dioxide concentration in the atmosphere is increasing, not decreasing.

Will the human species be able to come together and turn things around? Will humanity be able to avert a planet-wide catastrophe?

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