Thursday, November 14, 2013

Ocean pH and us, updated

By Joan Savage

 It has been said we land animals are creatures born of the seas. Our ancestors came to land as sacks of sea water, and our blood somewhat resembles seawater, or at least some patches of seawater: salty, full of nutrients, some oxygen, some carbon dioxide, some bicarbonate ion.

A recent BBC article on ocean acidification came with a jaunty, even flippant title, "Emissions of CO2 driving rapid oceans 'acid trip.' " I must point out that 'acid trip' connotes a youthful misadventure, albeit memorable. I didn't try LSD, but I've had to listen to those who did experiment on themselves, and they thought it was important.

'Acid trip' does not hint at irretrievable change in the oceans, so I am holding BBC accountable.  What is happening to the oceans is poisoning, and more like brain damage.

The BBC article included a sidebar of bulleted points, they are useful and I have cut and pasted here:

From BBC:


  • The oceans are thought to have absorbed up to half of the extra CO2 put into the atmosphere in the industrial age
  • This has lowered their pH by 0.1
  • pH is the measure of acidity and alkalinity
  • It usually ranges from pH 0 (very acidic) to pH 14 (very alkaline); 7 is neutral
  • Seawater is mildly alkaline with a "natural" pH of about 8.2
End BBC sidebar.

So,  the ocean's pH has already changed by 0.1.  Would it bother you if your coffee or tea's pH changed by 0.1? Probably not.

Consider this comparison instead.  Human arterial blood functions at a narrow range of pH, from pH 7.35 to pH 7.45. Outside of that range of pH range lies emergency situations and death. So the entire range of human blood's physiological health is 0.1.

The oceans have on average shifted by pH 0.1, the maximum pH shift that arterial blood in the human body could tolerate.

At what point does our mother the ocean become fatally ill and die?

Other news stories on ocean acidification:

1) Scientists warn of hot, sour, breathless oceans

By SETH BORENSTEIN, AP Science Writer   Updated 4:30 pm, Wednesday, November 13, 2013

"...the sweet spots where the factors combine are getting harder to find, Feely and Riebesell said.The world ocean pH already has gone from 8.1 to 8.0 — it's considered a 26 percent increase in acidity because scientists measure hydrogen ions for this."

No comments:

Post a Comment