Saturday, July 30, 2016

Shellfish, Ocean Acification, and Global Warming

I target my writing here at the layperson, so it may or may not be obvious to my readers that lots of things are happening to the ocean as a result of anthropogenic climate change, from coral reefs dying to sea level rise to changes in our fisheries to a mysterious "Warm Blob" in the Pacific (an actual thing!). Today I thought I'd try to tackle one of the causes of a few of those changes, Ocean Acidification. Ocean Acidification is an important point to understand when we're talking about the scale and consequences of global warming, and I hope to impart a bit of perspective on the matter here, if I can.

There's a lot of chemistry I'm not really gonna go into, but a little of it you have to understand, at least conceptually. First, a quick lesson on pH. I know you've seen that letter combination before, be it on lotion or soap or what have you, maybe you remember playing with pH paper in high school, but the thing to know is that it is a scale of measurement. Simply, it measures how acidic or basic something is, and those are opposite descriptors for the chemistry of a fluid based on the activity of the hydrogen ions in it. The scale runs from 0 to 14, where 7 is neutral, the low half of the scale is acidic and the upper half is basic. Lemon juice, for example, contains 5% to 6% citric acid and has a pH of between 2 and 3 (high acidity). The ocean is at a pH of around 8 (a little basic).

The thing to understand about pH is that this is a logarithmic scale. Like the Richter Scale used for measuring earthquake intensity, it isn't linear. We're not counting things, we're measuring intensity, in a range that boggles the human brain. A difference of 1 does not reflect an extra orange in a sack of oranges. Each mark on the scale is the previous mark multiplied by a value, not added to by a value. On the Richter scale a difference of one represents about a thirtyfold difference in magnitude. With pH, as mentioned, we're talking about the chemistry of the relative abundance of hydrogen ions, charged atoms. It takes a lot of those to change the pH of a cup of liquid you can hold in your hand. The numbers involved are beyond the capacity of the human brain to comprehend without some sort of shorthand to abbreviate things. You probably know that multiplying something by 2 over and over again gets you to astronomically high numbers really fast. Imagine doing that with a multiplier of 10 and you begin to understand pH.

So we have solid data to show that the pH of the ocean used to be more like 8.2, around 300 years ago, and over the last 200 years or so (thanks, Industrial Revolution!) it has edged up toward 8.1, which National Geographic will also spare you the math on and just tell you is about a 25% increase in acidity. That's a whole damn lot, which, when you think about how very big the ocean is, should scare you a whole damn lot. Because part of the carbon cycle of this planet involves the ocean soaking up CO2 from the atmosphere, forming carbonic acid (H2CO3) when it hits the water (H2O). This effect of the oceans soaking up our excess atmospheric carbon has definitely helped us by slowing the accumulation of greenhouse gasses that heats things up enough to melt glaciers and tundras, but we've generated so much CO2, so fast (think geologic timescales, now), that we're literally changing the chemistry of our planet. And it'll get worse. By one estimate, "if we continue our current rate of carbon emissions, global oceans could be 150 percent more acidic by the end of the century than they have been for 20 million years."

Look, we're not concerned the ocean is gonna turn into lemon juice. But we're pumping enough carbon into the ocean, that the acification is keeping sea life from functioning properly. That's why coral reefs are bleaching worldwide, and why the industry that harvests and sells mussels in Oregon is suffering. The higher acidity inhibits shell growth in marine animals. They literally can't make the chemistry of their bodies in the water function well enough to produce the calcium carbonate that they need for their shells, exoskeletons and other structures. The whole food chain is affected by this, including our fisheries.

Looks like a Dryer Ball to me.

There is so much we don't know about the ocean! We find new and previously assumed-to-be-extinct species, and we have absolutely no idea what this is! We have no idea what caused the Bloop (OK, we have some solid evidence to imply it was iceberg related, but still). We're still in the "observation" stage of understanding what the heck is going on with the Blob, as it is way too early to say we understand the process of it's generation even a tenth as well as we get the El Nino formation or what they call the "Pacific Decadal Oscillation." Hell, we can only sorta say we understand THOSE. We've looked at MAYBE 5% of the ocean and its depths, and the budget for NOAA (the National Oceanic & Atmospheric Administration) is less than a quarter of that of NASA. We need more Boaty McBoatfaces. We need more research, not just of what climate change is doing but of what's been out there all this time (my own alma mater is amazing on this front, btw).

Don't get me wrong, I love NASA. I love the technological marvels they've brought us over the years, and the exploration of space, and I have no desire to see NASA's budget cut, but NOAA definitely needs more, because they work to understand our planet's life support system. If we screw that up, there's no fixing it. Sorry to end on such a downer note, but that's were the science brings us.

Which is why (and I can say this, because this is a personal blog, and I choose to say it because we're in an election year) I will never vote for anyone who denies global warming. And you shouldn't either. That eliminates about 95% of a particular political party, in case you were wondering. Bear that in mind this November.

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