The “enhanced” greenhouse effect that wasn’t

Update (March 24th) at the end of this post – a kind of response from Feldman.

There was much ado recently about a new paper published in ‘Nature’ (“Observational determination of surface radiative forcing by CO2 from 2000 to 2010″ by Feldman et al.) claiming to have observed a strengthening in CO2-specific “surface radiative forcing” at two sites in North America going from 2000 to the end of 2010 (a period of 11 years) of about 0.2 W/m2 per decade, and through this observation further claiming how they have shown empirically (allegedly for the first time outside the laboratory) how the rise in atmospheric CO2 concentration directly and positively affects the surface energy balance, by adding more and more energy to it as “back radiation” (“downwelling longwave (infrared) radiation” (DWLWIR)), thus – by implication – leading to surface warming.

In other words, Feldman et al. claim to have obtained direct empirical evidence – from the field – of a strengthening of the “greenhouse effect”, a result, it would seem, lending considerable support to the hypothesis that our industrial emissions of CO2 and other similar gaseous substances to the atmosphere has enhanced, and is indeed enhancing still, the Earth’s atmospheric rGHE, thus causing a warming global surface – the AGW proposition.

From the abstract:

(…) we present observationally based evidence of clear-sky CO2 surface radiative forcing that is directly attributable to the increase, between 2000 and 2010, of 22 parts per million atmospheric CO2.”


“These results confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions, and provide empirical evidence of how rising CO2 levels (…) are affecting the surface energy balance.”

So the question is: Do these results really “confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions”?

Of course they don’t. As usual, the warmists refuse to look at the whole picture, insisting rather on staying inside the tightly confined space of their own little bubble model world. Continue reading

The greenhouse effect that wasn’t (Part 2)





First, what is the rGHE supposed to do?

It is supposed to make the surface below a radiatively active atmosphere warmer than if this particular kind of atmosphere weren’t there. By extension, one could claim – and this is after all what the ‘Anthropogenic Global Warming hypothesis’ is all about – that the stronger the rGHE, the stronger its warming effect.

Now, as far as I’m concerned, this is a prediction that should be possible to test. Or else, what good is it?

Again, what is the strictest definition of the rGHE? What is its ‘surface warming mechanism’ supposed to be, in the simplest of terms? We went through this in Part 1, where what was defined as the “greenhouse effect” of clouds was overwhelmed by their opposing “albedo effect”, leading to an overall – net – cooling effect.

It is found simply and solely in the reduction in outgoing radiative (LWIR) flux from the surface to the top of the atmosphere (ToA) – the surface flux minus the ToA flux. (The surface flux is calculated directly from the surface temperature (based on a blackbody assumption, through the Stefan-Boltzmann equation), while the ToA flux is rather estimated from actual measurements made by satellite-borne instruments.)

The prediction, then, would go as follows: Continue reading