Jump!

A while ago I posted about the fact that the dip in Mauna Loa CO2 data for March of 2008, as noted in a post by Anthony Watts, was really nothing out of the ordinary. The “event” was a drop in the seasonally adjusted CO2 level, a circumstance which is not very common but by no means extraordinary.

Watts didn’t just note the “event,” he believed he knew the probable cause:

In the graph above, the black line is the seasonally adjusted value while the red is the monthly mean. This is based on data through March. May is normally the peak month. Here we see how Mauna Loa CO2 has lagged in its annual rise. The likely culprit: Pacific ocean cooling due to La Nina and increased solubility of CO2 in water.

Of course Watts used it to suggest a number of ludicrous ideas, including:

Given that May is normally the peak month for CO2, and because we still see a strong La Nina, the result could be a lower CO2 max in 2008 than 2007 for Mauna Loa. This has happened before in the 60s and 70s in the last cool PDO phase (lasting til 1977). Even if it stays even with last year’s level, this tells us a lot and sheds doubt on these ideas:

1. Anthropogenic accumulation (civilization is still producing CO2)
2. A CO2 residence time of several hundred years seems unlikely now
3. Giegengack’s thesis that if man stopped emitting CO2, the earth would emit more to compensate, the premise being that since man has for the first time “upset the balance” and is pressing CO2 into the earth, then once the balance is restored the earth will resume emitting it instead.

This is really a typical Wattsism: take anything you can find, even if it’s based on so little data as to be utterly meaningless and isn’t really out of the ordinary anyway, and use it to suggest ludicrous ideas which of course fit Watts’ nutjob notions about how our atmosphere is changing. In this case, we should doubt that man-made CO2 is accumulating in the atmosphere and that extra CO2 will stay in the atmosphere for centuries. As for Giegengack … one nutjob at a time, please.

So I showed in the previous post that the drop in March of 2008 really wasn’t anything out of the ordinary. This spurred Lucia to go on and on about how there was a TWO-MONTH drop in the seasonally adjusted Mauna Loa CO2 data, so my rebuttal had to be utter nonsense and of course I’m an idiot because I didn’t address the issue of the TWO-MONTH drop. Watts didn’t even mention the TWO-MONTH drop in his post, although apparently the subject came up in comments, he just made outlandish nutjob suggestions like “sheds doubt on … Anthropogenic accumulation”. No, it doesn’t, and there’s really NO DOUBT that anthropogenic CO2 emissions are accumulating in the atmosphere. None. If you doubt that, you’re not a skeptic: you’re a nutjob.

Was this “event” the harbinger of a downturn in CO2 at Mauna Loa? Has a cooling Pacific sucked the CO2 out of the air? Here’s the seasonally adjusted data through June of this year, together with a linear regression line:

Well gosh.

It’s not just a royal swift-boating to focus on a completely irrelevant blip in an attempt to sew the seeds of doubt on things about which there really is no doubt. It’s also a pity, because there are interesting aspects of the Mauna Loa CO2 record which one would never notice without giving all the data its due and applying some actual analysis. For example: atmospheric CO2 hasn’t increased in a perfectly smooth way, not even if you remove the seasonal pattern to produce “seasonally adjusted” values. The increase is marked by random variations as well as anthropogenic increase. There’s been quite a bit of research into the causes of those variations, most of the plausible speculation having to do with changes in the biosphere and its uptake of CO2. If we look at the entire time span of Mauna Loa data, the raw data look like this:

and the seasonally adjusted values look like this:

It’s evident (and statistically significant) that the rate of increase of CO2 has itself increased; atmospheric CO2 is growing quite a bit faster now than it was when measurements at Mauna Loa began. Presently, the atmospheric CO2 concentration is about 386 ppmv, and it’s increasing at about 2 ppmv/yr. At that rate, we’ll hit 426 ppmv in 20 years.

That could be important. A reader recently posted a link to an article which claims that 426 ppmv is the maximum safe concentration of atmospheric CO2, but not because of climate change. It’s because, claims the article, when people are exposed to increased CO2 — not just for 8 hours a day 5 days a week, but all the time, it causes reduced blood pH (blood acidosis), which brings a host of health risks including restlessness, hypertension, somnolence, confusion, a reduced desire to indulge in physical activity, and over the long term even embryonic or fetal abnormalities. The threat will be greatest for the elderly and those with existing respiratory conditions; the additional strain on health care and the discomfort and risk for the entire population will cause severe strain on society, including all of us living in the industrialized world.

I’m not qualified to evaluate the correctness of this paper but I have to admit that it’s scary. Yet I suspect that it exaggerates the risk of 426 ppmv CO2 levels. I really don’t know. And I certainly wouldn’t want to jump to any conclusions.

At the end of his post Watts stated,

It will be interesting to see in the coming months what happens globally, should we see a drop-off or leveling of global CO2 in response to our quiet sun and La Nina, it will be difficult for AGW proponents to explain.

Has he bothered to inform his readers subsequently that no, there was no levelling-off of global (or Mauna Loa) CO2, and that his suggestion that “this tells us a lot and sheds doubt on these ideas” is difficult to explain? It seems not. But he has continued to post nutjob ideas about CO2, including a hit-and-run implication that Mauna Loa data are unreliable because the measurements are taken near a volcano, for which he really didn’t bother to do any research on the issue. But fermiparadox has already posted about that. Twice.

UPDATE:

For a really good laugh read this, then read this and this.