2011-05-29 01:08:131000 ppm of C02 would be ideal -- New rebuttal needed?
John Hartz
John Hartz

"The author criticized the work of Leighton Steward, a recognized expert on the subject, who was asked to speak at the Copenhagen Climate Change Conference in December 2009, and again at the 4th International Conference on Climate Change held in Chicago in May 2010. Steward’s research strongly suggests that we need more carbon dioxide in the atmosphere, not less. Presently, we have about 385 parts per million in our air, and Steward suggests that about 1,000 parts per million would be ideal."

The above is excerpted from a guest op-ed posted appearing in today's (May 28) edition of the Billings (Montana) Gazette. This op-ed was penned by Bill Ballard, CEO of Ballard Petroleum in Billings, and past president of Montana Petroleum Association, and previously taught geology at Rocky Mountain College. No surprise about where he is coming from.

Until reading this op-ed, I had never heard of Leighton Steward or his pronouncement about 1000 ppm.

Does this warrant a SkS rebuttal?

I suspect that many geologists working in the petroleum industry subscribe to the phony-baloney articulated in Ballard's op-ed. Is this viewpoint prevalent among geologists working in other fields and in academia?

2011-05-29 01:17:55


Well, this should give you an idea of his arguments.

There is plenty of SkS material to rebut those.

2011-05-29 05:40:10
Rob Painting

Probably worth a rebuttal at some stage. Ocean acidification?    

2011-05-29 05:48:34
Dana Nuccitelli

We don't have anything specific to this, but a lot of relevant posts.  Like the 2°C danger limit (Monckton Myth #5), John's post on the Pliocene (similar CO2 level to today) having sea level 25 meters higher, my post on the 6th mass extinction event, "it's not bad", "it's not urgent", acidification, etc.  I also asked Ove H-G to give a CO2 concentration that would be really bad for the Great Barrier Reef in his post on the subject.

2011-05-29 06:32:41My concern
John Hartz
John Hartz

I know there is plenty of material posted on SkS to rebute this specific matter.

Coming at from the perspective of someone posting on a comment thread who wants to locate rebuttal information quickly, when I key in "Leighton Steward" into the SkS search box and get nothing, I may not pursue the matter further on the SkS website.

The more user friendly we can make SkS, the more it will be used.

2011-05-29 11:27:31I suggest doing a blog post on this
John Cook


And if there is more than one example of the "1000ppm is good" argument around, make it a rebuttal also.

I did a "what was it like when CO2 levels were last like now" post, looking at the Pliocene when CO2 was around 350 to 400 ppm. I'd been meaning to do a sequel, "what was it like when CO2 levels were last at business as usual levels?", looking at what it was like at 1000ppm. We're looking at sea levels even higher than 25 metres than present, crazy scary stuff. A blog post on this topic and rebutting Leighton Steward at the same time would be great.

2011-05-29 11:36:16
Rob Painting

Badger, are you volunteering?

2011-05-29 13:34:37
James Wight


This extremely worrying Climate Progress post is relevant:


The study referred to examines what the global climate was like 30-40 Ma, the most recent possible time that CO2 was at 1,000 ppm. It estimates the globe was 16°C warmer at that time, implying a climate sensitivity of about 8°C. I suppose if Hansen is right that CO2 was less than 550 ppm at 35 Ma, then climate sensitivity would be even higher.

If only we had an IPCC-like report bringing together all this paleoclimate evidence to derive the true worst-case scenario. Right now it’s difficult to tell a consistent story based on paleoclimate, but as Romm says, paleoclimate is far more worrying than the models.

2011-05-29 22:17:06Trade & comment
John Hartz
John Hartz

Rob: 'll crank out a first-cut draft on this one if you will "take back" the post on why SLR is not uniform.

All: I've been reluctant to volunteer to draft either rebuttals or articles because my understanding of climate science is very basic -- especially in comparison to most of you.  


2011-05-29 22:50:17You may want to read this as well
Daniel Bailey
Daniel Bailey

Significant Role Played by Oceans in Ancient Global Cooling

ScienceDaily (May 28, 2011) — Thirty-eight million years ago, tropical jungles thrived in what are now the cornfields of the American Midwest and furry marsupials wandered temperate forests in what is now the frozen Antarctic. The temperature differences of that era, known as the late Eocene, between the equator and Antarctica were only half of what they are today. A debate has long been raging in the scientific community on what changes in our global climate system led to such a major shift from the more tropical, greenhouse climate of the Eocene to the modern and much cooler climates of today.

New research published in the journal Science, led by Rensselaer Polytechnic Institute scientist Miriam Katz, is providing some of the strongest evidence to date that the Antarctic Circumpolar Current (ACC) played a key role in the major shift in the global climate that began approximately 38 million years ago. The research provides the first evidence that early ACC formation played a vital role in the formation of the modern ocean structure.

The paper, titled "Impact of Antarctic Circumpolar Current development on late Paleogene ocean structure," is published in the May 27, 2011, issue of Science.

"What we have found is that the evolution of the Antarctic Circumpolar Current influenced global ocean circulation much earlier than previous studies have shown," said Katz, who is assistant professor of earth and environmental science at Rensselaer. "This finding is particularly significant because it places the impact of initial shallow ACC circulation in the same interval when the climate began its long-term shift to cooler temperatures."

There has been a debate over the past 40 years on what role the Antarctic Circumpolar Current had in the underlying cooling trend on Earth. Previous research has placed the development of the deep ACC (greater than 2,000 meters water depth) in the late Oligocene (approximately 23-25 million years ago). This is well after the global cooling pattern had been established. With this research, Katz and her colleagues used information from ocean sediments to place the global impact of the ACC to approximately 30 million years ago, when it was still just a shallow current.

Oceans and global temperatures are closely linked. Warmer ocean waters result in warmer air temperatures and vice versa. In the more tropical environs of the Eocene, ocean circulation was much weaker and currents were more diffuse. As a result, heat was more evenly distributed around the world. This resulted in fairly mild oceans and temperatures worldwide, according to Katz. Today, ocean temperatures vary considerably and redistribute warm and cold water around the globe in significant ways.

"As the global ocean currents were formed and strengthened, the redistribution of heat likely played a significant role in the overall cooling of the Earth," Katz said.

And no current is more significant than the ACC. Often referred to as the "Mixmaster" of the ocean, the ACC thermally isolates Antarctica by preventing warm surface waters from subtropical gyres to pass through its current. The ACC instead redirects some of that warm surface water back up toward the North Atlantic, creating the Antarctic Intermediate Water. This blocking of heat enabled the formation and preservation of the Antarctic ice sheets, according to Katz. And it is this circumpolar circulation that Katz's research concludes was responsible for the development of our modern four-layer ocean current and heat distribution system.

To come to her conclusions, Katz looked at the uptake of different elemental isotopes in the skeletons of small organisms found in ocean sediments. The organisms, known as benthic foraminifera, are found in extremely long cores of sediments drilled from the bottom of the ocean floor.

During their lifetime, foraminifera incorporate certain elements and elemental isotopes depending on environmental conditions. By analyzing the ratios of different isotopes and elements, the researchers are able to reconstruct the past environmental conditions that surrounded the foraminifera during their life. Specifically, they looked at isotopes of oxygen and carbon, along with ratios of magnesium versus calcium. More detailed information on Katz's isotopic analysis methods can be found at http://green.rpi.edu/archives/fossils/index.html.

Analysis of these isotopes from sediment cores extracted directly off the North American Atlantic coast showed the earliest evidence for the Antarctic Intermediate Waters, which circulates strictly as a direct consequence of the ACC. This finding is the first evidence of the effects of shallow ACC formation. The findings place development of the ACC's global impact much closer to the time that Antarctica separated from South America. It had previously been thought that the currents moving through this new continental gateway could not be strong enough at such shallow depths to affect global ocean circulation.

Katz points out that the larger cooling trend addressed in the paper has been punctuated by many short, but often significant, episodes of global warming. Such ancient episodes of warming are another significant aspect of her research program, and play an important role in understanding the modern warming of the climate occurring on the planet.

"By reconstructing the climates of the past, we can provide a science-based means to explore or predict possible system responses to the current climate change," Katz said.

Katz is joined in the research by Benjamin Cramer of Theiss Research; J.R. Toggweiler of Geophysical Fluid Dynamics Lab/NOAA; Chengjie Liu of ExxonMobil Exploration Co.; Bridget Wade of University of Leeds; and Gar Esmay, Kenneth Miller, Yair Rosenthal, and James Wright of Rutgers University.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Rensselaer Polytechnic Institute.

Journal Reference:

  1. M. E. Katz, B. S. Cramer, J. R. Toggweiler, G. Esmay, C. Liu, K. G. Miller, Y. Rosenthal, B. S. Wade, J. D. Wright. Impact of Antarctic Circumpolar Current Development on Late Paleogene Ocean Structure. Science, 2011; 332 (6033): 1076 DOI: 10.1126/science.1202122
2011-05-29 23:36:15
Rob Painting

Err, righto Badger, but the "SLR is not uniform" post is a real bastard! It'll have to go right to the back of the "to do" list.

And don't worry, there's help available here in the forum. I felt the same way you did, but I look at it this way: this is the greatest crisis mankind has ever faced and it is time critical, we are among the few who understand the danger and are in the right place at the right time to at least try to make a positive difference. Why not give it a go?

As far as scientific understanding, I think it's a mistake to buy into the normal nonsense that goes on in the comments section (arguing minutia and complexity), explaining the science so that a general audience can understand it, should be the objective. Authors here seem to have their own area of expertise, and that's likely to be due to a focus on a particular area. I've read over 200 papers on the Amazon rainforest for instance!, and I ain't no scientist. What I found is that even on the climate blogs there are plenty of neglected topics, where it seems virtually no one in the blogosphere has actually done a great deal of reading. I'm sure there's one or two topics which push your button more than others, maybe you could thoroughly research those?

2011-05-30 00:07:19Serendipity
John Hartz
John Hartz

Daniel: I saw the write-up about the article in ScienceDaily's Environmental Headlines just a few minutes ago and thought to myself, "This looks interesting. I'll do a general chat post about it if it hasn't been flagged already." Great minds think alike -- and subscribe to the same e-bulletins.