Quotes and charts are from “Global Temperature Update thru 2012” Hansen, Sato & Ruedy 13, Jan 2012 Charts of US temperatures are from an August 1999 GISS paper by Hansen et al as seen on WUWT
James Hansen the Head of the Goddard Institute for Space Studies has determined that it isn’t a reduction in CO2 emissions, an increase in aerosols, a change in the solar output or a phase-out of ozone depleting chemicals. So what does he say is the cause? “
“The more important factor in the standstill is probably unforced dynamical variability, essentially climatic noise.”
This is a first! There are several first’s in this paper, at least for Hansen.
He defines this period of stable temperature as the 5 year running average over the past decade. This is pretty much an admission of unchanged temperature for the past 15 years. Climate alarmists like to use running averages. In the IPCC AR4, there was a 5-year running average chart of global temperature anomalies that completely removed the stasis of temperature over the first 6 years of the century, leading one to believe global warming was still continuing. It had stopped.
Speaking of the 5 year running average, here is his chart of global Land-Ocean temperatures from Hansen’s paper complete with volcano occurrences and relative ENSO effect. :
As an aside, beyond the scope of this analysis, an email came across the lines today about Hansen’s temperature chart relative to the warmest year in the US. Seems as though 1930 used to be 0.6°C warmer than 1998. Now 2012 beats out 1998 by 0.2°C. Current adjusted data puts 1930’s out of the running when it was actually the warmest ever, at least in the last 100years or so and warmer than 2012. This was first explained by Steve McIntyre.
The 4-plate figure above is really quite curious. The normal curve in a stable process, in this case temperature anomaly, would remain approximately stationary. Given the base period, including a cool period in the 20th century, it is no wonder that the curve has moved to the right. If you were to look back into climate history, you would see that many of today’s warming alarmists were global cooling alarmists in the 70’s. Hansen was key among them, so he knows that the 60’s and 70’s were anomalously cooler, for some reason, even if he was wrong about the cause. To use this as the base period is misleading at best, and completely dishonest at the worst. Unless Hansen is a complete statistical illiterate, I would lean towards the latter. Just my opinion… A shift in a normal distribution requires a significant change. Hansen accomplished that by reducing SO2 emissions. I am somewhat doubtful that is true, but he claims it worked so take credit for it. When the temperature anomaly shift becomes statistically significant is anyone’s guess, but clearly the right two plates are a real change. The obvious question is not answered but we know Hansen thinks it’s our fault with CO2 emissions. I would contend that the difference is related to natural causes, not the least of which is magnetic field intensities relating to the Sun. But what do I know…Let’s call it “noise”.
Hansen lists several factors that have not caused the stasis of global temperature. How he does this will likely not be reported in the MSM but his reasoning is quite curious given his past stances.
One of the most amazing, to me, was this paragraph wherein he discusses CO2 emissions:
“The largest climate forcing is caused by increasing greenhouse gases, principally CO2 (Fig. 5).
The annual increment in the greenhouse gas forcing (Fig. 5) has declined from about 0.05 W/m2 in the 1980s to about 0.35(changed to 0.035) W/m2 in recent years.”
There are a number of issues here, not the least of which is how one declines from 0.05W/sq-m to 0.35Wsq-m which is the recent change in the incremental greenhouse gas forcing. (Just received notification from Hansen of an error in the original report. 0.35 S/B 0.035.Someone clued him in.) He credits a reduction of methane emissions as part of the answer. OK????
Regarding CO2, he claims the
“airborne fraction of fossil fuel CO2 emissions has declined.”
WHAT!!?? That is quite a turnaround! With 1/3 of all the emissions ever emitted having been emitted since 1992, or thereabouts, and the alarmist claim of long lifespan of CO2 in the atmosphere, why would he acknowledge that the fraction of airborne concentrations are declining? I see this as quite a revelation. It reminds me of Lord Monckton admonishing a scientist from NCDC at a Congressional hearing, a Mr. Karl, that despite an increasing rate of CO2 emissions, the rate of increase of the atmospheric percentage of airborne CO2 was not changing. Hansen goes a step further and acknowledges the airborne emissions have decreased.
He then goes on to write:
“and the forcing per CO2 increment declines slowly as CO2 increases due to partial saturation of absorption bands, so the CO2 forcing growth rate has been steady despite the rapid growth of fossil fuel emissions.”
This apparently acknowledges the long held position by realists that concentrations of CO2 have less effect as their concentrations grow. “Partial” and “saturation” would appear to be countering each other. As is claimed by many, 95% would not likely be referred to as “partial”. I would classify this as almost completely saturated. Clearly, Hansen’s admission, although he played it down by careful choice of words, implies there really is a limit to the amount of warming one could expect from CO2.
As an astronomer, Hansen’s academic area of expertise, one would assign Dr. Hansen more of an understanding of extraterrestrial climate “forcings” but alas you would be wrong. He continues to cite the tired “total solar irradiance” as the prime candidate for solar climate driver. Most solar scientists will tell you the largest factor is the magnetic intensity interacting with our planet, and some also include magnetic polarity as a major factor. Hansen is apparently completely oblivious to this mechanism. Admittedly, it is probably not completely understood and Hansen would never accept any half-baked hypothesis. Right? As the story goes, the weakened solar magnetic field allows more Galactic Cosmic Rays to enter the solar system with a modulating effect on the Sun’s solar wind. The Sun’s polarity switches on an 11year timescale, adding or subtracting from the net Solar-terrestrial field. When the net field is weaker more energetic particles enter our atmosphere, and group together forming cloud nucleation particles resulting in condensation. Clouds are thus formed, cooling the planet. Even small changes in global cloud cover can have significant effects on our climate. There are other hypotheses that have been identified.
Of course we can’t forget the Solar Inertial Motion (SIM) hypothesis where the large planets whip the Sun around causing the Sun to orbit in an Epitrochoid,178 year pattern. We are now in a small loop in this pattern, generally resulting in cooler temperatures. Further amplification of this hypothesis came from Ivanka Charvatova, a scientist from the Czech Republic, who introduces a disordered trefoil, her description of what some call an epitrochoid, where a longer cooling period than the typical ~30 year pattern is possible. She says we are entering such a period.
Several commenters on WUWT felt that Hansen was actually softening his position on Climate Change, incorporating several sceptic contentions in this paper in anticipation of the whole house of cards falling apart. As we approach the peak of solar cycle 24, I suspect in the next 20 years there will be many climate changes including lower temps, more snow, cooler summers, shorter growing seasons, growing ice caps, energy shortages due to government policy incompetence, some pretty violent weather due to significant N-S swings of the jet stream, reduced airborne CO2 concentrations and falling sea level. Oh yes! And a lot of unemployed, re-faced, climate alarmists. Except for the incompetent policy decisions, it won’t be our fault.