Ocean "Acidity" Mythology

Since Mr. Hunt continues citing a “30% increase in ocean acidity” caused by a change in pH from 8.2 to 8.1, in the interest of scientific accuracy this error demands correction. The equation for the pH of an aqueous solution is logarithmic and defined as pH = -log[ H+ ] .  There are 14 orders of magnitude that define the pH scale from zero to fourteen units as per this equation, so a lowering of alkalinity of .1 units pH cannot equal a 30% increase in acidity as claimed. It is actually .1/14 or only 0.7%. The natural variation of ocean pH can be up to 5% in either direction, making meaningless a variation plus or minus 0.7%.

Neutral pH is 7.0, so acidification is not appropriate terminology. A reduction in pH from 8.2 to 8.1 is a lowering of alkalinity, not an increase in acidification.

“There has historically been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period (200 mya), average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm -- about 18 times higher than today.

“The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today-- 4400 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today.”

Ocean "Acidity" Myth

Since Mr. Hunt repeats the same two limited studies of Atlantic sediments and Oregon oysters in each of his letters, I’ll provide information about the science involved.

The oceans have remained alkaline during the last 540 million years.

Rainwater (pH 5.6) reacts with the most common minerals on Earth (feldspars) to produce clays, which consume acids, then alkali is leached into the oceans (making them salty), silica is redeposited in sediments, which consumes acid and is accelerated by temperature. Sea water has a local and regional variation in pH  (7.8 to 8.3, but ranging from 7 to 9 in Chesapeake Bay). Since pH is a log scale, there is not enough CO2 in fossil fuels to create oceanic acidity because most of the planet’s CO2 is locked up in rocks. 

In the Precambrian, reactions rapidly responded to huge changes in climate (-40°F to +122°F), large sea level changes (+1,968’ to -2,100’) and rapid climate shifts from ‘snowball’ or ‘slushball’ Earth to very hot. About 750 million years ago life started to extract huge amounts of CO2 from the oceans, life expanded and diversified, and this process continues (which is why we have low CO2 today).

The history of CO2 and temperature shows no correlation. Compared to now: CO2 was 15 times higher in the Ordovician-Silurian glaciation (ice age). Both methane and CO2 were higher in the Permian glaciation. CO2 was 5 times higher in the Cretaceous-Jurassic glaciation. 

The atmosphere once had at least 25 times the current CO2 content, and now CO2 is the lowest it has been for billions of years.

Algae blooms fed by sewage runoff cause increased alkalinity in less salty areas of bays, and higher acidity closer to the open ocean, so atmospheric CO2 is not a factor. Someone should tell those Oregon oysters.

Climate Models Have No Clothes

The climate models have no clothes. They have no predictive ability. The proof that they don’t is in the observations of what has happened compared to model predictions. Warming is at a standstill. So is sea level rise. Glaciers in Glacier Bay retreated ten times more from 1780 to 1912 as 1912 to present. Warming still precedes CO2 increases. The “hot spot” ain’t there. Severe weather is not as severe as it used to be. A review of cycles of glaciation and warming during the past 500,000 years show Earth is now in what is established as long periods of glaciation and short inter-glacials.

Ocean pH was 0.8 units lower and atmospheric CO2 was five times higher one hundred million years ago (when marine invertebrates had already been established and successful for over four hundred million years). Recent studies show that some marine invertebrates do better in higher acidity, and that models using strong acids have led to incorrect conclusions about increased ocean acidity. Since very little CO2 absorbed in water becomes carbonic acid, it has very little effect on pH anyway Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14 – since we have many studies that show the warming ending the Little Ice Age began about three hundred years ago, the relationship between current warming, CO2, and ocean acidification seems specious. Since CO2 is released to the atmosphere as oceans warm, there is a disconnect between oceans warming and atmospheric CO2 being absorbed by the oceans. It would appear more likely that oceans would have absorbed CO2 and created more carbonic acid during the Little Ice Age than during the warming that followed. Since atmospheric warming following the Little Ice Age would have preceded ocean warming, a timeline of decreasing pH over three hundred years ago makes more sense.

But back to models. If the models were right, US temperature would have increased at least three times the 1 degree F since 1900 (with most of the increase in the 1930′s). Sea levels would be up more than 6 inches since 1999, instead of less than one inch. Major hurricanes would be hitting the US annually, instead of none in over 3 years. Texas temperatures would be up more than the observed 0.04 degree F since 1884. Or to put it simply, the models would not be so crappy at predicting the future, or in explaining the past.

Ocean Acidity Scare Debunked

A writer to our Gualala weekly newspaper noted (Oyster evidence, ICO, May 11, 2012) that acidity of the oceans are increasing “at a rate in the last 100 years that is 10 times faster than any 100-year span in the last 300 million years.” This is interesting on many levels, most conspicuously because it’s not true. An obvious fault is that ocean pH changes cannot be measured in precise 100-year increments covering the past 300 million years.  However, there’s more.

A 2005 study (Pelejero et al.) spanning the period 1708-1988 found a clear interdecadal oscillation of pH between 7.9 and 8.2 pH units. The study showed many oscillations of 0.2 pH units within the three 100-year periods examined.

A 2009 study (Liu et al.) of the pH history of the South China Sea covering the past 7,000 years shows oscillations of 0.4 pH units, some of which decreased 0.2 pH units in a 100-year period.  About recent increases in ocean acidity, this study concluded: “(T)here is nothing unusual, unnatural or unprecedented about the two most recent pH values. They are neither the lowest of the record, nor is the decline rate that led to them the greatest of the record.”

It’s hard for a statement about acidity increasing “faster than any 100-year span in the last 300 million years” to be true when the rate isn’t the even the fastest in the last 300 years, as one study shows, or in the last 7,000 years per another study.

A 2009 Australian study (Wei et al.) found a decrease in pH of 0.4 units 1935-1940, and an earlier decrease of 0.3 units 1860-1865. Both of these reductions, as all of the previous examples, were obviously not caused by increased atmospheric CO2. It is also obvious that Oregon oysters survived them all, and should persevere.

(The writer sent another letter to our weekly newspaper that basically repeated his first letter without the slightest indication that he had read my refutation above)

According to him, a Columbia University study found we had increased the ocean’s acidity, in his words, “10 times faster than any time in the last 300 million years,” but that’s not what it says. Its headline is “Ocean Acidification Rate May Be Unprecedented,” and the report findings are qualified with the word “may” throughout.

The pH change in question is only a decrease from 8.2 to 8.1 in 200 years. To put this in perspective, a 2011 study, Hofmann, et al., High-Frequency Dynamics of Ocean pH: A Multi-Ecosystem Comparison, found many non-open ocean sites where pH varied by up to 1.4 units in a month. In the more stable and vast open ocean, Hofmann wrote: “Open-water areas (in the Southern Ocean) experience a strong seasonal shift in seawater pH (~0.3–0.5 units) between austral summer and winter.”

A Mediterranean experiment found that corals and mollusks transplanted to lower pH sites were “able to calcify and grow at even faster than normal rates when exposed to the high [carbon-dioxide] levels projected for the next 300 years.” That’s not surprising, since corals and shellfish evolved with CO2 levels 10-20 times higher than present.

Contradicting the Oregon State oyster study he cited, a 2012 Parker et al. study of Sydney rock oysters found that "larvae spawned from adults exposed to elevated CO2 were larger and developed faster" than those from nearby ambient seawater. This study exposed the flaw in the Oregon study that only considered the impacts on larvae, ignoring the carry-over effects passed from adult to offspring.

A 2012 Armin et al. study of cold-water coral found it acclimated quickly and appeared to increase growth under lower pH levels. Again, science robustly debunks ocean acidification fears and alarmism.

We have nothing to fear but Al Gore himself.