From the “settled science” department comes this new revision of Earth’s entire radiation budget. Many WUWT readers can recall seeing this radiation budget graphic from Kenneth Trenberth in 2009:
Source: Trenberth et al. 2009 http://echorock.cgd.ucar.edu/cas/Staff/Fasullo/my_pubs/Trenberth2009etalBAMS.pdf
That figure in a slightly different form also appeared in the 2007 IPCC AR4 WG1 report with different numbers:
Note that in Trenberth’s 2009 paper, the energy from “back radiation” (from GHG action) value went up from 324 w/square meter cited by the IPCC in 2007 to 333 w/square meter. The net effect of that is increased energy back to Earth’s surface, making it warmer.
It seems odd that would increase so much, so quickly in two years. Even more surprising, is that now, the value has been revised even higher, to 340.3 w/square meter, while at the same time, the “Net Absorbed” value, that extra bit of energy that we get to keep from the sun on Earth, thanks to increased GHG action, has gone DOWN.
I know, it doesn’t make much sense, read on.
Alan Siddons writes in an email:
Reviewing NASA’s Earth Radiation Budget (ERB) program this week, I noticed a graphic depiction I hadn’t seen before, at
Cooler sun than before but a warmer surface. Less albedo and air absorption. Non-radiative cooling is higher than before but surface emission is higher too. “Net absorbed” refers to radiant energy going in but not yet being radiated – a ticking time bomb.
Note that somehow, between 2009 and the present, it was decided (presumably based on CERES measurements) that the Net Absorbed value (which is the extra energy absorbed that would result from increased GHG’s) would go DOWN from 0.9 w/square meter to 0.6w/square meter – an decrease of one third of the 2009 value.
This isn’t a typo, since many of the other numbers have changed as well.
With all the talk of the “settled science” that is certain about increases in Greenhouse gases, it seems that with such a revision, there’s still some very unsettled revisionist work afoot to get a handle on what the “real” energy budget of the Earth is. Perhaps the recent published works on climate sensitivity, coupled with observations of “the pause” have had some affect on these numbers as well. Meanwhile, according to the Mauna Loa data, CO2 concentration has risen from 388.16ppm in November 2009 when we had the big Copenhagen COP15 meeting that was supposed to change everything, to 397.31ppm in November 2013.
So with GHG’s on the increase, their effect has been reduced by a third in the NASA planetary energy budget. That’s quite remarkable.
So was Trenberth’s 2009 energy budget wrong, running too hot? It sure seems so. This is what NASA writes about that diagram:
The energy budget diagram on the front shows our best understanding of energy flows into and away from the Earth. It is based on the work of many scientists over more than 100 years, with the most recent measurements from the Clouds and the Earth’s Radiant Energy System (CERES; http://ceres.larc.nasa.gov) satellite instrument providing high accuracy data of the radiation components (reflected solar and emitted infrared radiation fluxes).
This energy balance determines the climate of the Earth. Our understanding of these energy flows will continue to evolve as scientists obtain a longer and longer record using new and better instruments (http://clarreo.larc.nasa.gov).
It seems to be a clear case of observations trumping Trenberth.
So with the retained energy (the net absorbed figure) resulting from GHG’s like CO2 dropping by one third since 2009, can we now call off some of the most alarming aspects of global warming theory?
Alan Siddons writes in with some further research. Commenter John West also noted this in comments. Siddons writes:
Well, let me tell you what I found while tracking down that IPCC illustration. I did find it on an IPCC document, Regional Changes of Climate and some basic concepts , but it looked shabby there too, so I surmised that it was a careless copy-paste of somebody else’s work, not a product of the IPCC itself. On that basis I searched for “radiation budget” or “energy budget” and added the illustration’s particular figures to my search demand.
Bingo. The illustration actually came from a May 2013 American Institute of Physics paper, A new diagram of the global energy balance , by Martin Wild, et al.
Here’s a small version for your records.
Other notes by Wild, Decadal changes in surface radiative fluxes – overview and update , yield some insight into his perspective — for instance, this panel,
which seems to indicate that less sunlight creates more compensatory back-radiation but a weaker terrestrial emission, while more sunlight “unmasks” the greenhouse effect. Wild’s conclusions are also notable.
- Still considerable uncertainties in global mean radiation budget at the surface.
- Models still tend to overestimate downward solar and underestimate downward thermal radiation
- Strong decadal changes observed in both surface solar and thermal fluxes.
This last point seems to imply that changes to the Radiation Budget are not merely a result of improved measurements but reflect rather sudden changes in our thermal environment.
This leads me to wonder, why did NASA choose the values from Wild et al as opposed to Trenberth from the National Center For Atmosphereic Research?