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Friday, June 25, 2010

PNAS - Proc. National Academy of Sciences, has two blunt online advance edition open access articles about climate change and about black carbon atmospheric emission mitigation.

PNAS is a leading reference, accorded great trust within the scientific community. It is unlike some politically slanted "think tank" output from on the DC beltway, saying what lobbyists and politicians tell it to say - paying the piper and calling the tune being the old saying.

PNAS is generally thought to represent the anthithesis of that kind of disingenuous, slanted approach to scientific and technological discourse.

Climate change skeptics might not like what the weight of this PNAS authority indicates.

First, this online link, (with the abstracts set out below and with both entire articles online and downloadable as pdfs), Expert credibility in climate change:

Although preliminary estimates from published literature and expert surveys suggest striking agreement among climate scientists on the tenets of anthropogenic climate change (ACC), the American public expresses substantial doubt about both the anthropogenic cause and the level of scientific agreement underpinning ACC. A broad analysis of the climate scientist community itself, the distribution of credibility of dissenting researchers relative to agreeing researchers, and the level of agreement among top climate experts has not been conducted and would inform future ACC discussions. Here, we use an extensive dataset of 1,372 climate researchers and their publication and citation data to show that (i) 97–98% of the climate researchers most actively publishing in the field surveyed here support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.

Second, this online link, Assessing the climatic benefits of black carbon mitigation:

To limit mean global warming to 2 °C, a goal supported by more than 100 countries, it will likely be necessary to reduce emissions not only of greenhouse gases but also of air pollutants with high radiative forcing (RF), particularly black carbon (BC). Although several recent research papers have attempted to quantify the effects of BC on climate, not all these analyses have incorporated all the mechanisms that contribute to its RF (including the effects of BC on cloud albedo, cloud coverage, and snow and ice albedo, and the optical consequences of aerosol mixing) and have reported their results in different units and with different ranges of uncertainty. Here we attempt to reconcile their results and present them in uniform units that include the same forcing factors. We use the best estimate of effective RF obtained from these results to analyze the benefits of mitigating BC emissions for achieving a specific equilibrium temperature target. For a 500 ppm CO2e (3.1 W m-2) effective RF target in 2100, which would offer about a 50% chance of limiting equilibrium warming to 2.5 °C above preindustrial temperatures, we estimate that failing to reduce carbonaceous aerosol emissions from contained combustion would require CO2 emission cuts about 8 years (range of 1–15 years) earlier than would be necessary with full mitigation of these emissions.

I understand all the points global warming skeptics raise, e.g., Mike Jungbauer out here in the north-metro. Rather than setting any such argument down and giving counterargument here; I urge any interested reader to track Jungbauer down and ask for his evidence even more than his opinions. Then read these complete items, do further study, and decide for yourself whether the peer review process at PNAS is or is not more credible than Mike Jungbauer's self-professed expertise.

And in thinking over the question, do weigh the notions of global economy becoming ever more interlocked and the beliefs that some would like to tightly engineer and control the relative growth rates of constituent economies, and that widespread acceptance of the climate change arguments could aid such intentions, should they actually exist. Proving that there is too much will to manage among "them," "the elite," is likely a harder thing to prove decisively than whether the climate is changing as a result of greater carbon [energy] consumption arising from global industrialization, from ever increasing prevalence of internal combustion engines, etc.