“April Fools Day” seems precisely the right day to post news unveiling an ongoing “April Fools” trick—intentional or not—by the National Oceanic and Atmospheric Administration, a trick in which climate alarmists have—again, intentionally or not—participated.

AGW alarmists, perhaps frustrated by the failure of Earth’s atmosphere to warm as predicted (or projected, or simulated, or whatever you want to call it) by the global climate models, have in recent years turned increasingly to claims that rising atmospheric CO2 concentration threatens to bring about “ocean acidification,” which, they claim, would have all kinds of disastrous consequences for marine, and therefore other, life. And they present graphs showing decline in ocean pH (a decline they call “acidification,” although the result is still well within the basic rather than the acidic range of pH).

But now it turns out that at least some of the graphs showing this decline originate not with actual measurements of ocean pH but with—you guessed it—computer models of ocean pH! You know, like the computer models of “average global temperature” that don’t match real-world observations.

And the scandal is that those computer model pH trends were substituted for real-world data, without telling anyone it was being done.

Hydrologist Michael Wallace tells the story in “Ocean pH Accuracy Argument Challenged with 80 Years of Instrumental Data.” Here’s an excerpt:

Figure 1-a. includes a subset of the FEEL2899 pH time series product as the thick reddish curve. Some aspects of the          NOAA World Ocean Database (WOD) (6) global ocean pelagic pH data (GOPpH) are plotted over the same time frame. These include the ten year moving average in blue, and a rounded version of that as open green circles. Please note that although there doesn’t appear to be a clear trend up or down, both of the WOD-based curves suggest an oscillatory behavior, over the period shown.

NOAA’s WOD pH data are typically published to two decimal places. This is presumably because of the 0.01 pH unit accuracy of the meters utilized. This accuracy is standard for many modern day glass electrode pH (GEpH) meters as well. In addition, the natural global ocean pH (GOpH) values for all depths can range over 4 full pH units.   That yields at least 400 unique possibilities along a continuous ocean pH curve, that can be accurately identified by any pH meter of its time.   Even a measurement taken with an accuracy of only one decimal place yields 40 possible points along that curve. Either accuracy should be more than adequate for initial and publishable GOpH and/or GOPpH trend analyses.

As a rough illustration, I have included the green open circles of Figure 1.a., which are simply the blue curve data rounded to the nearest 0.1 pH unit. The apparent oscillatory pattern of the more refined time series is preserved. This holds even though I’ve already severely restricted the pH range of that data set due to the 10 year averaging filter.

In short, the real-world data show oscillation in pH but no clear trend. It’s only the model results that picture a (downward) trend. I.e., the models are wrong.